nginx-site: xml/en/docs/njs/node

annotate xml/en/docs/njs/node_modules.xml @ 2489:bda080989b6c

Fixed indentation and braces in njs example.

author	Vladimir Homutov <vl@nginx.com>
date	Wed, 22 Jan 2020 13:10:07 +0300
parents	8ed243471444
children	4c8d0b37932d

rev	line source
2480 73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	1 <?xml version="1.0"?>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	2
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	3 <!--
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	4 Copyright (C) Nginx, Inc.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	5 -->
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	6
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	7 <!DOCTYPE article SYSTEM "../../../../dtd/article.dtd">
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	8
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	9 <article name="Using node modules with njs"
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	10 link="/en/docs/njs/node_modules.html"
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	11 lang="en"
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	12 rev="3">
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	13
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	14 <section id="intro" name="Introduction">
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	15
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	16 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	17 Often, a developer wants to use 3rd-party code, usually available as a library
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	18 of some kind.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	19 In the Javascript world, the concept of a module is relatively new, so there
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	20 was no standard until recently.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	21 Many platforms (browsers) still don't support modules, which makes code
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	22 reuse harder.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	23 The njs does not (yet) support modules, too.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	24 This article describes ways to overcome this limitation, using the
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	25 <link url="https://nodejs.org/">Node.js</link> ecosystem as an example.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	26 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	27
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	28 <note>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	29 Examples in this article use features that appeared in
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	30 <link doc="index.xml">njs</link>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	31 <link doc="changes.xml" id="njs0.3.8">0.3.8</link>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	32 </note>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	33
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	34 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	35 There is a number of issues that may arise when 3rd-party code is added to njs:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	36
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	37 <list type="bullet">
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	38
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	39 <listitem>Multiple files that reference each other, and their
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	40 dependencies</listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	41
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	42 <listitem>Platform-specific APIs</listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	43
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	44 <listitem>Modern standard language constructions</listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	45
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	46 </list>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	47
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	48 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	49
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	50 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	51 The good news is that such problems are not something new or
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	52 specific to njs.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	53 Javascript developers face them daily when trying to support multiple
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	54 disparate platforms with very different properties.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	55 There are instruments designed to resolve the above-mentioned issues.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	56 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	57
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	58 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	59
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	60 <list type="bullet">
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	61
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	62 <listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	63 Multiple files that reference each other, and their dependencies
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	64 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	65 This can be solved by merging all the interdependent code into a single file.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	66 Tools like
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	67 <link url="http://browserify.org/">browserify</link> or
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	68 <link url="https://webpack.js.org/">webpack</link>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	69 accept an entire project and produce a single file containing
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	70 your code and all the dependencies.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	71 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	72 </listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	73
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	74 <listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	75 Platform-specific APIs
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	76 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	77 You can use multiple libraries that implement such APIs in a platform-agnostic
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	78 manner (at the expense of performance, though).
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	79 Particular features can also be implemented using the
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	80 <link url="https://polyfill.io/v3/">polyfill</link> approach.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	81 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	82 </listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	83
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	84 <listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	85 Modern standard language constructions
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	86 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	87 Such code can be transpiled: this means performing a number of transformations
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	88 that rewrite newer language features in accordance with an older standard.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	89 For example, <link url="https://babeljs.io/"> babel</link> project can
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	90 be used to this purpose.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	91 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	92 </listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	93
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	94 </list>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	95
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	96 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	97
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	98
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	99 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	100 In this guide, we will use two relatively large npm-hosted libraries:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	101
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	102 <list type="bullet">
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	103
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	104 <listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	105 <link url="https://www.npmjs.com/package/protobufjs">protobufjs</link> -
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	106 a library for creating and parsing protobuf messages used by the
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	107 <link url="https://grpc.io/">gRPC</link> protocol.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	108
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	109 </listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	110
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	111 <listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	112 <link url="https://www.npmjs.com/package/dns-packet">dns-packet</link> -
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	113 a library for processing DNS protocol packets.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	114 </listitem>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	115
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	116 </list>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	117
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	118 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	119
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	120 </section>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	121
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	122 <section id="environment" name="Environment">
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	123
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	124 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	125
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	126 <note>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	127 This document mostly employs a generic approach and AVOIDS specific best
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	128 practice advices concerning Node.js and the rapidly evolving JavaScript
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	129 ecosystem.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	130 Make sure to consult the corresponding package's manual BEFORE following the
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	131 steps suggested here.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	132 </note>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	133
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	134 First (assuming Node.js is installed and operational), let's create an
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	135 empty project and install some dependencies; the commands below assume we're
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	136 in the working directory:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	137
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	138 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	139 $ mkdir my_project && cd my_project
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	140 $ npx license choose_your_license_here > LICENSE
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	141 $ npx gitignore node
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	142
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	143 $ cat > package.json <<EOF
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	144 {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	145 "name": "foobar",
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	146 "version": "0.0.1",
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	147 "description": "",
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	148 "main": "index.js",
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	149 "keywords": [],
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	150 "author": "somename <some.email@example.com> (https://example.com)",
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	151 "license": "some_license_here",
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	152 "private": true,
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	153 "scripts": {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	154 "test": "echo \"Error: no test specified\" && exit 1"
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	155 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	156 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	157 EOF
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	158 $ npm init -y
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	159 $ npm install browserify
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	160 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	161 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	162
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	163 </section>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	164
2481 8ed243471444 Typos fixed. Vladimir Homutov <vl@nginx.com> parents: 2480 diff changeset	165 <section id="protobuf" name="Protobufjs">
2480 73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	166
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	167 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	168 The library provides a parser for the <literal>.proto</literal> interface
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	169 definitions and a code generator for message parsing and generation.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	170 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	171
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	172 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	173 In this example, we will use the
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	174 <link url="https://github.com/grpc/grpc/blob/master/examples/protos/helloworld.proto">helloworld.proto</link>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	175 file from the gRPC examples.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	176 Our goal is to create two messages: <literal>HelloRequest</literal> and
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	177 <literal>HelloResponse</literal>.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	178 We will use the
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	179 <link url="https://github.com/protobufjs/protobuf.js/blob/master/README.md#reflection-vs-static-code">static</link>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	180 mode of protobufjs instead of dynamically generating classes, because
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	181 njs doesn't support adding new functions dynamically due to security
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	182 considerations.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	183 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	184
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	185 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	186 Next, the library is installed and javascript code implementing
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	187 message marshalling is generated from the protocol definition:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	188 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	189 $ npm install protobufjs
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	190 $ npx pbjs -t static-module helloworld.proto > static.js
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	191 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	192
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	193 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	194
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	195 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	196 Thus, the <literal>static.js</literal> file becomes our new dependency, storing
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	197 all the code we need to implement message processing.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	198 The <literal>set_buffer()</literal> function contains code that uses the
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	199 library to create a buffer with the serialized <literal>HelloRequest</literal>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	200 message.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	201 The code resides in the <literal>code.js</literal> file:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	202
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	203 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	204 var pb = require('./static.js');
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	205
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	206 // Example usage of protobuf library: prepare a buffer to send
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	207 function set_buffer(pb)
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	208 {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	209 // set fields of gRPC payload
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	210 var payload = { name: "TestString" };
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	211
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	212 // create an object
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	213 var message = pb.helloworld.HelloRequest.create(payload);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	214
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	215 // serialize object to buffer
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	216 var buffer = pb.helloworld.HelloRequest.encode(message).finish();
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	217
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	218 var n = buffer.length;
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	219
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	220 var frame = new Uint8Array(5 + buffer.length);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	221
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	222 frame[0] = 0; // 'compressed' flag
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	223 frame[1] = (n & 0xFF000000) >>> 24; // length: uint32 in network order
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	224 frame[2] = (n & 0x00FF0000) >>> 16;
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	225 frame[3] = (n & 0x0000FF00) >>> 8;
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	226 frame[4] = (n & 0x000000FF) >>> 0;
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	227
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	228 frame.set(buffer, 5);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	229
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	230 return frame;
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	231 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	232
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	233 var frame = set_buffer(pb);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	234 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	235 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	236
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	237 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	238 To ensure it works, we execute the code using node:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	239
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	240 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	241 $ node ./code.js
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	242 Uint8Array [
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	243 0, 0, 0, 0, 12, 10,
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	244 10, 84, 101, 115, 116, 83,
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	245 116, 114, 105, 110, 103
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	246 ]
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	247 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	248
2481 8ed243471444 Typos fixed. Vladimir Homutov <vl@nginx.com> parents: 2480 diff changeset	249 You can see that this got us a properly encoded <literal>gRPC</literal> frame.
2480 73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	250 Now let's run it with njs:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	251
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	252 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	253 $ njs ./code.js
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	254 Thrown:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	255 Error: Cannot find module "./static.js"
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	256 at require (native)
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	257 at main (native)
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	258 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	259 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	260
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	261 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	262 Modules are not supported, so we've received an exception.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	263 To overcome this issue, let's use <literal>browserify</literal>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	264 or other similar tool.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	265 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	266
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	267 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	268 An attempt to process our existing <literal>code.js</literal> file will result
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	269 in a bunch of JS code that is supposed to run in a browser, i.e. immediately
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	270 upon loading.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	271 This isn't something we actually want.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	272 Instead, we want to have an exported function that
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	273 can be referenced from the nginx configuration.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	274 This requires some wrapper code.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	275
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	276 <note>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	277 In this guide, we use njs cli in all examples for the sake of simplicity.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	278 In real life, you will be using nginx njs module to run your code.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	279 </note>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	280
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	281 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	282
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	283 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	284 The <literal>load.js</literal> file contains the library-loading code that
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	285 stores its handle in the global namespace:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	286 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	287 global.hello = require('./static.js');
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	288 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	289 This code will be replaced with merged content.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	290 Our code will be using the "<literal>global.hello</literal>" handle to access
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	291 the library.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	292 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	293
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	294 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	295 Next, we process it with browserify to get all dependencies into a single file:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	296 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	297 $ npx browserify load.js -o bundle.js -d
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	298 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	299
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	300 The result is huge file that contains all our dependencies:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	301
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	302 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	303 (function(){function......
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	304 ...
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	305 ...
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	306 },{"protobufjs/minimal":9}]},{},[1])
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	307 //# sourceMappingURL..............
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	308 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	309
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	310 To get final "<literal>njs_bundle.js</literal>" file we concatenate
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	311 "<literal>bundle.js</literal>" and the following code:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	312
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	313 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	314 // Example usage of protobuf library: prepare a buffer to send
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	315 function set_buffer(pb)
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	316 {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	317 // set fields of gRPC payload
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	318 var payload = { name: "TestString" };
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	319
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	320 // create an object
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	321 var message = pb.helloworld.HelloRequest.create(payload);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	322
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	323 // serialize object to buffer
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	324 var buffer = pb.helloworld.HelloRequest.encode(message).finish();
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	325
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	326 var n = buffer.length;
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	327
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	328 var frame = new Uint8Array(5 + buffer.length);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	329
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	330 frame[0] = 0; // 'compressed' flag
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	331 frame[1] = (n & 0xFF000000) >>> 24; // length: uint32 in network order
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	332 frame[2] = (n & 0x00FF0000) >>> 16;
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	333 frame[3] = (n & 0x0000FF00) >>> 8;
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	334 frame[4] = (n & 0x000000FF) >>> 0;
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	335
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	336 frame.set(buffer, 5);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	337
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	338 return frame;
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	339 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	340
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	341 // functions to be called from outside
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	342 function setbuf()
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	343 {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	344 return set_buffer(global.hello);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	345 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	346
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	347 // call the code
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	348 var frame = setbuf();
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	349 console.log(frame);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	350 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	351
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	352 Let's run the file using node to make sure things still work:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	353 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	354 $ node ./njs_bundle.js
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	355 Uint8Array [
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	356 0, 0, 0, 0, 12, 10,
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	357 10, 84, 101, 115, 116, 83,
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	358 116, 114, 105, 110, 103
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	359 ]
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	360 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	361
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	362 Now let's proceed further with njs:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	363
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	364 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	365 $ /njs ./njs_bundle.js
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	366 Uint8Array [0,0,0,0,12,10,10,84,101,115,116,83,116,114,105,110,103]
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	367 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	368
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	369 The last thing will be to use njs-specific API to convert
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	370 array into byte string, so it could be usable by nginx module.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	371 We can add the following snippet before the last line:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	372 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	373 if (global.njs) {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	374 return String.bytesFrom(frame)
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	375 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	376 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	377
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	378 Finally, we got it working:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	379
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	380 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	381 $ njs ./njs_bundle.js \|hexdump -C
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	382 00000000 00 00 00 00 0c 0a 0a 54 65 73 74 53 74 72 69 6e \|.......TestStrin\|
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	383 00000010 67 0a \|g.\|
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	384 00000012
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	385 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	386 This is the intended result.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	387 Response parsing can be implemented similarly:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	388 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	389 function parse_msg(pb, msg)
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	390 {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	391 // convert byte string into integer array
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	392 var bytes = msg.split('').map(v=>v.charCodeAt(0));
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	393
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	394 if (bytes.length < 5) {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	395 throw 'message too short';
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	396 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	397
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	398 // first 5 bytes is gRPC frame (compression + length)
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	399 var head = bytes.splice(0, 5);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	400
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	401 // ensure we have proper message length
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	402 var len = (head[1] << 24)
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	403 + (head[2] << 16)
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	404 + (head[3] << 8)
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	405 + head[4];
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	406
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	407 if (len != bytes.length) {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	408 throw 'header length mismatch';
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	409 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	410
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	411 // invoke protobufjs to decode message
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	412 var response = pb.helloworld.HelloReply.decode(bytes);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	413
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	414 console.log('Reply is:' + response.message);
2489 bda080989b6c Fixed indentation and braces in njs example. Vladimir Homutov <vl@nginx.com> parents: 2481 diff changeset	415 }
2480 73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	416 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	417 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	418
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	419 </section>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	420
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	421 <section id="dnspacket" name="DNS-packet">
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	422
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	423 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	424 This example uses a library for generation and parsing of DNS packets.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	425 This a case worth considering because the library and its dependencies
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	426 use modern language constructions not yet supported by njs.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	427 In turn, this requires from us an extra step: transpiling the source code.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	428 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	429
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	430 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	431 Additional node packages are needed:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	432 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	433 $ npm install @babel/core @babel/cli @babel/preset-env babel-loader
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	434 $ npm install webpack webpack-cli
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	435 $ npm install buffer
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	436 $ npm install dns-packet
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	437 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	438
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	439 The configuration file, webpack.config.js:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	440 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	441 const path = require('path');
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	442
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	443 module.exports = {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	444 entry: './load.js',
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	445 mode: 'production',
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	446 output: {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	447 filename: 'wp_out.js',
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	448 path: path.resolve(__dirname, 'dist'),
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	449 },
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	450 optimization: {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	451 minimize: false
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	452 },
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	453 node: {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	454 global: true,
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	455 },
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	456 module : {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	457 rules: [{
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	458 test: /\.m?js$$/,
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	459 exclude: /(bower_components)/,
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	460 use: {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	461 loader: 'babel-loader',
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	462 options: {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	463 presets: ['@babel/preset-env']
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	464 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	465 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	466 }]
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	467 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	468 };
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	469 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	470 Note we are using "<literal>production</literal>" mode.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	471 In this mode webpack does not use "<literal>eval</literal>" construction
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	472 not supported by njs.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	473
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	474 The referenced <literal>load.js</literal> file is our entry point:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	475 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	476 global.dns = require('dns-packet')
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	477 global.Buffer = require('buffer/').Buffer
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	478 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	479
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	480 We start the same way, by producing a single file for the libraries:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	481
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	482 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	483 $ npx browserify load.js -o bundle.js -d
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	484 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	485
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	486 Next, we process the file with webpack, which itself invokes babel:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	487
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	488 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	489 $ npx webpack --config webpack.config.js
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	490 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	491
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	492 This command produces the <literal>dist/wp_out.js</literal> file, which is a
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	493 transpiled version of <literal>bundle.js</literal>.
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	494
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	495 We need to concatenate it with <literal>code.js</literal>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	496 that stores our code:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	497
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	498 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	499 function set_buffer(dnsPacket)
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	500 {
2489 bda080989b6c Fixed indentation and braces in njs example. Vladimir Homutov <vl@nginx.com> parents: 2481 diff changeset	501 // create DNS packet bytes
bda080989b6c Fixed indentation and braces in njs example. Vladimir Homutov <vl@nginx.com> parents: 2481 diff changeset	502 var buf = dnsPacket.encode({
bda080989b6c Fixed indentation and braces in njs example. Vladimir Homutov <vl@nginx.com> parents: 2481 diff changeset	503 type: 'query',
bda080989b6c Fixed indentation and braces in njs example. Vladimir Homutov <vl@nginx.com> parents: 2481 diff changeset	504 id: 1,
bda080989b6c Fixed indentation and braces in njs example. Vladimir Homutov <vl@nginx.com> parents: 2481 diff changeset	505 flags: dnsPacket.RECURSION_DESIRED,
bda080989b6c Fixed indentation and braces in njs example. Vladimir Homutov <vl@nginx.com> parents: 2481 diff changeset	506 questions: [{
bda080989b6c Fixed indentation and braces in njs example. Vladimir Homutov <vl@nginx.com> parents: 2481 diff changeset	507 type: 'A',
bda080989b6c Fixed indentation and braces in njs example. Vladimir Homutov <vl@nginx.com> parents: 2481 diff changeset	508 name: 'google.com'
bda080989b6c Fixed indentation and braces in njs example. Vladimir Homutov <vl@nginx.com> parents: 2481 diff changeset	509 }]
bda080989b6c Fixed indentation and braces in njs example. Vladimir Homutov <vl@nginx.com> parents: 2481 diff changeset	510 })
2480 73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	511
2489 bda080989b6c Fixed indentation and braces in njs example. Vladimir Homutov <vl@nginx.com> parents: 2481 diff changeset	512 return buf;
2480 73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	513 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	514 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	515
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	516 Note that in this example generated code is not wrapped into function and we
2481 8ed243471444 Typos fixed. Vladimir Homutov <vl@nginx.com> parents: 2480 diff changeset	517 do not need to call it explicitly.
8ed243471444 Typos fixed. Vladimir Homutov <vl@nginx.com> parents: 2480 diff changeset	518 The result is in the "<literal>dist</literal>" directory:
2480 73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	519
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	520 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	521 $ cat dist/wp_out.js code.js > njs_dns_bundle.js
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	522 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	523
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	524 Let's call our code at the end of a file:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	525 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	526 var b = setbuf(1);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	527 console.log(b);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	528 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	529
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	530 And execute it using node:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	531
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	532 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	533 $ node ./njs_dns_bundle_final.js
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	534 Buffer [Uint8Array] [
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	535 0, 1, 1, 0, 0, 1, 0, 0,
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	536 0, 0, 0, 0, 6, 103, 111, 111,
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	537 103, 108, 101, 3, 99, 111, 109, 0,
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	538 0, 1, 0, 1
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	539 ]
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	540 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	541
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	542 Make sure this works as expected, and then run it with njs:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	543 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	544 $ njs ./njs_dns_bundle_final.js
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	545 Uint8Array [0,1,1,0,0,1,0,0,0,0,0,0,6,103,111,111,103,108,101,3,99,111,109,0,0,1,0,1]
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	546 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	547
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	548 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	549
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	550 <para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	551 The response can be parsed as follows:
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	552 <example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	553 function parse_response(buf)
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	554 {
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	555 var bytes = buf.split('').map(v=>v.charCodeAt(0));
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	556
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	557 var b = global.Buffer.from(bytes);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	558
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	559 var packet = dnsPacket.decode(b);
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	560
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	561 var resolved_name = packet.answers[0].name;
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	562
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	563 // expected name is 'google.com', according to our request above
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	564 }
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	565 </example>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	566
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	567 </para>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	568
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	569 </section>
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	570
73d254c3376d Added the "Using node modules with njs" article. Vladimir Homutov <vl@nginx.com> parents: diff changeset	571 </article>

Mercurial > hg > nginx-site

annotate xml/en/docs/njs/node_modules.xml @ 2489:bda080989b6c