Mercurial > hg > nginx
view src/http/modules/ngx_http_memcached_module.c @ 6755:e2f13011343e stable-1.10
HTTP/2: fixed the "http request count is zero" alert.
When the stream is terminated the HEADERS frame can still wait in the output
queue. This frame can't be removed and must be sent to the client anyway,
since HTTP/2 uses stateful compression for headers. So in order to postpone
closing and freeing memory of such stream the special close stream handler
is set to the write event. After the HEADERS frame is sent the write event
is called and the stream will be finally closed.
Some events like receiving a RST_STREAM can trigger the read handler of such
stream in closing state and cause unexpected processing that can result in
another attempt to finalize the request. To prevent it the read handler is
now set to ngx_http_empty_handler.
Thanks to Amazon.
author | Valentin Bartenev <vbart@nginx.com> |
---|---|
date | Thu, 16 Jun 2016 20:55:11 +0300 |
parents | f01ab2dbcfdc |
children | 1d0e03db9f8e |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { ngx_http_upstream_conf_t upstream; ngx_int_t index; ngx_uint_t gzip_flag; } ngx_http_memcached_loc_conf_t; typedef struct { size_t rest; ngx_http_request_t *request; ngx_str_t key; } ngx_http_memcached_ctx_t; static ngx_int_t ngx_http_memcached_create_request(ngx_http_request_t *r); static ngx_int_t ngx_http_memcached_reinit_request(ngx_http_request_t *r); static ngx_int_t ngx_http_memcached_process_header(ngx_http_request_t *r); static ngx_int_t ngx_http_memcached_filter_init(void *data); static ngx_int_t ngx_http_memcached_filter(void *data, ssize_t bytes); static void ngx_http_memcached_abort_request(ngx_http_request_t *r); static void ngx_http_memcached_finalize_request(ngx_http_request_t *r, ngx_int_t rc); static void *ngx_http_memcached_create_loc_conf(ngx_conf_t *cf); static char *ngx_http_memcached_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child); static char *ngx_http_memcached_pass(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_conf_bitmask_t ngx_http_memcached_next_upstream_masks[] = { { ngx_string("error"), NGX_HTTP_UPSTREAM_FT_ERROR }, { ngx_string("timeout"), NGX_HTTP_UPSTREAM_FT_TIMEOUT }, { ngx_string("invalid_response"), NGX_HTTP_UPSTREAM_FT_INVALID_HEADER }, { ngx_string("not_found"), NGX_HTTP_UPSTREAM_FT_HTTP_404 }, { ngx_string("off"), NGX_HTTP_UPSTREAM_FT_OFF }, { ngx_null_string, 0 } }; static ngx_command_t ngx_http_memcached_commands[] = { { ngx_string("memcached_pass"), NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF|NGX_CONF_TAKE1, ngx_http_memcached_pass, NGX_HTTP_LOC_CONF_OFFSET, 0, NULL }, { ngx_string("memcached_bind"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_http_upstream_bind_set_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.local), NULL }, { ngx_string("memcached_connect_timeout"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_msec_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.connect_timeout), NULL }, { ngx_string("memcached_send_timeout"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_msec_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.send_timeout), NULL }, { ngx_string("memcached_buffer_size"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_size_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.buffer_size), NULL }, { ngx_string("memcached_read_timeout"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_msec_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.read_timeout), NULL }, { ngx_string("memcached_next_upstream"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE, ngx_conf_set_bitmask_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.next_upstream), &ngx_http_memcached_next_upstream_masks }, { ngx_string("memcached_next_upstream_tries"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_num_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.next_upstream_tries), NULL }, { ngx_string("memcached_next_upstream_timeout"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_msec_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.next_upstream_timeout), NULL }, { ngx_string("memcached_gzip_flag"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_num_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, gzip_flag), NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_memcached_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ ngx_http_memcached_create_loc_conf, /* create location configuration */ ngx_http_memcached_merge_loc_conf /* merge location configuration */ }; ngx_module_t ngx_http_memcached_module = { NGX_MODULE_V1, &ngx_http_memcached_module_ctx, /* module context */ ngx_http_memcached_commands, /* module directives */ NGX_HTTP_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static ngx_str_t ngx_http_memcached_key = ngx_string("memcached_key"); #define NGX_HTTP_MEMCACHED_END (sizeof(ngx_http_memcached_end) - 1) static u_char ngx_http_memcached_end[] = CRLF "END" CRLF; static ngx_int_t ngx_http_memcached_handler(ngx_http_request_t *r) { ngx_int_t rc; ngx_http_upstream_t *u; ngx_http_memcached_ctx_t *ctx; ngx_http_memcached_loc_conf_t *mlcf; if (!(r->method & (NGX_HTTP_GET|NGX_HTTP_HEAD))) { return NGX_HTTP_NOT_ALLOWED; } rc = ngx_http_discard_request_body(r); if (rc != NGX_OK) { return rc; } if (ngx_http_set_content_type(r) != NGX_OK) { return NGX_HTTP_INTERNAL_SERVER_ERROR; } if (ngx_http_upstream_create(r) != NGX_OK) { return NGX_HTTP_INTERNAL_SERVER_ERROR; } u = r->upstream; ngx_str_set(&u->schema, "memcached://"); u->output.tag = (ngx_buf_tag_t) &ngx_http_memcached_module; mlcf = ngx_http_get_module_loc_conf(r, ngx_http_memcached_module); u->conf = &mlcf->upstream; u->create_request = ngx_http_memcached_create_request; u->reinit_request = ngx_http_memcached_reinit_request; u->process_header = ngx_http_memcached_process_header; u->abort_request = ngx_http_memcached_abort_request; u->finalize_request = ngx_http_memcached_finalize_request; ctx = ngx_palloc(r->pool, sizeof(ngx_http_memcached_ctx_t)); if (ctx == NULL) { return NGX_HTTP_INTERNAL_SERVER_ERROR; } ctx->request = r; ngx_http_set_ctx(r, ctx, ngx_http_memcached_module); u->input_filter_init = ngx_http_memcached_filter_init; u->input_filter = ngx_http_memcached_filter; u->input_filter_ctx = ctx; r->main->count++; ngx_http_upstream_init(r); return NGX_DONE; } static ngx_int_t ngx_http_memcached_create_request(ngx_http_request_t *r) { size_t len; uintptr_t escape; ngx_buf_t *b; ngx_chain_t *cl; ngx_http_memcached_ctx_t *ctx; ngx_http_variable_value_t *vv; ngx_http_memcached_loc_conf_t *mlcf; mlcf = ngx_http_get_module_loc_conf(r, ngx_http_memcached_module); vv = ngx_http_get_indexed_variable(r, mlcf->index); if (vv == NULL || vv->not_found || vv->len == 0) { ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "the \"$memcached_key\" variable is not set"); return NGX_ERROR; } escape = 2 * ngx_escape_uri(NULL, vv->data, vv->len, NGX_ESCAPE_MEMCACHED); len = sizeof("get ") - 1 + vv->len + escape + sizeof(CRLF) - 1; b = ngx_create_temp_buf(r->pool, len); if (b == NULL) { return NGX_ERROR; } cl = ngx_alloc_chain_link(r->pool); if (cl == NULL) { return NGX_ERROR; } cl->buf = b; cl->next = NULL; r->upstream->request_bufs = cl; *b->last++ = 'g'; *b->last++ = 'e'; *b->last++ = 't'; *b->last++ = ' '; ctx = ngx_http_get_module_ctx(r, ngx_http_memcached_module); ctx->key.data = b->last; if (escape == 0) { b->last = ngx_copy(b->last, vv->data, vv->len); } else { b->last = (u_char *) ngx_escape_uri(b->last, vv->data, vv->len, NGX_ESCAPE_MEMCACHED); } ctx->key.len = b->last - ctx->key.data; ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http memcached request: \"%V\"", &ctx->key); *b->last++ = CR; *b->last++ = LF; return NGX_OK; } static ngx_int_t ngx_http_memcached_reinit_request(ngx_http_request_t *r) { return NGX_OK; } static ngx_int_t ngx_http_memcached_process_header(ngx_http_request_t *r) { u_char *p, *start; ngx_str_t line; ngx_uint_t flags; ngx_table_elt_t *h; ngx_http_upstream_t *u; ngx_http_memcached_ctx_t *ctx; ngx_http_memcached_loc_conf_t *mlcf; u = r->upstream; for (p = u->buffer.pos; p < u->buffer.last; p++) { if (*p == LF) { goto found; } } return NGX_AGAIN; found: line.data = u->buffer.pos; line.len = p - u->buffer.pos; if (line.len == 0 || *(p - 1) != CR) { goto no_valid; } *p = '\0'; line.len--; ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "memcached: \"%V\"", &line); p = u->buffer.pos; ctx = ngx_http_get_module_ctx(r, ngx_http_memcached_module); mlcf = ngx_http_get_module_loc_conf(r, ngx_http_memcached_module); if (ngx_strncmp(p, "VALUE ", sizeof("VALUE ") - 1) == 0) { p += sizeof("VALUE ") - 1; if (ngx_strncmp(p, ctx->key.data, ctx->key.len) != 0) { ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "memcached sent invalid key in response \"%V\" " "for key \"%V\"", &line, &ctx->key); return NGX_HTTP_UPSTREAM_INVALID_HEADER; } p += ctx->key.len; if (*p++ != ' ') { goto no_valid; } /* flags */ start = p; while (*p) { if (*p++ == ' ') { if (mlcf->gzip_flag) { goto flags; } else { goto length; } } } goto no_valid; flags: flags = ngx_atoi(start, p - start - 1); if (flags == (ngx_uint_t) NGX_ERROR) { ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "memcached sent invalid flags in response \"%V\" " "for key \"%V\"", &line, &ctx->key); return NGX_HTTP_UPSTREAM_INVALID_HEADER; } if (flags & mlcf->gzip_flag) { h = ngx_list_push(&r->headers_out.headers); if (h == NULL) { return NGX_ERROR; } h->hash = 1; ngx_str_set(&h->key, "Content-Encoding"); ngx_str_set(&h->value, "gzip"); r->headers_out.content_encoding = h; } length: start = p; p = line.data + line.len; u->headers_in.content_length_n = ngx_atoof(start, p - start); if (u->headers_in.content_length_n == NGX_ERROR) { ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "memcached sent invalid length in response \"%V\" " "for key \"%V\"", &line, &ctx->key); return NGX_HTTP_UPSTREAM_INVALID_HEADER; } u->headers_in.status_n = 200; u->state->status = 200; u->buffer.pos = p + sizeof(CRLF) - 1; return NGX_OK; } if (ngx_strcmp(p, "END\x0d") == 0) { ngx_log_error(NGX_LOG_INFO, r->connection->log, 0, "key: \"%V\" was not found by memcached", &ctx->key); u->headers_in.content_length_n = 0; u->headers_in.status_n = 404; u->state->status = 404; u->buffer.pos = p + sizeof("END" CRLF) - 1; u->keepalive = 1; return NGX_OK; } no_valid: ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "memcached sent invalid response: \"%V\"", &line); return NGX_HTTP_UPSTREAM_INVALID_HEADER; } static ngx_int_t ngx_http_memcached_filter_init(void *data) { ngx_http_memcached_ctx_t *ctx = data; ngx_http_upstream_t *u; u = ctx->request->upstream; if (u->headers_in.status_n != 404) { u->length = u->headers_in.content_length_n + NGX_HTTP_MEMCACHED_END; ctx->rest = NGX_HTTP_MEMCACHED_END; } else { u->length = 0; } return NGX_OK; } static ngx_int_t ngx_http_memcached_filter(void *data, ssize_t bytes) { ngx_http_memcached_ctx_t *ctx = data; u_char *last; ngx_buf_t *b; ngx_chain_t *cl, **ll; ngx_http_upstream_t *u; u = ctx->request->upstream; b = &u->buffer; if (u->length == (ssize_t) ctx->rest) { if (ngx_strncmp(b->last, ngx_http_memcached_end + NGX_HTTP_MEMCACHED_END - ctx->rest, bytes) != 0) { ngx_log_error(NGX_LOG_ERR, ctx->request->connection->log, 0, "memcached sent invalid trailer"); u->length = 0; ctx->rest = 0; return NGX_OK; } u->length -= bytes; ctx->rest -= bytes; if (u->length == 0) { u->keepalive = 1; } return NGX_OK; } for (cl = u->out_bufs, ll = &u->out_bufs; cl; cl = cl->next) { ll = &cl->next; } cl = ngx_chain_get_free_buf(ctx->request->pool, &u->free_bufs); if (cl == NULL) { return NGX_ERROR; } cl->buf->flush = 1; cl->buf->memory = 1; *ll = cl; last = b->last; cl->buf->pos = last; b->last += bytes; cl->buf->last = b->last; cl->buf->tag = u->output.tag; ngx_log_debug4(NGX_LOG_DEBUG_HTTP, ctx->request->connection->log, 0, "memcached filter bytes:%z size:%z length:%O rest:%z", bytes, b->last - b->pos, u->length, ctx->rest); if (bytes <= (ssize_t) (u->length - NGX_HTTP_MEMCACHED_END)) { u->length -= bytes; return NGX_OK; } last += (size_t) (u->length - NGX_HTTP_MEMCACHED_END); if (ngx_strncmp(last, ngx_http_memcached_end, b->last - last) != 0) { ngx_log_error(NGX_LOG_ERR, ctx->request->connection->log, 0, "memcached sent invalid trailer"); b->last = last; cl->buf->last = last; u->length = 0; ctx->rest = 0; return NGX_OK; } ctx->rest -= b->last - last; b->last = last; cl->buf->last = last; u->length = ctx->rest; if (u->length == 0) { u->keepalive = 1; } return NGX_OK; } static void ngx_http_memcached_abort_request(ngx_http_request_t *r) { ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "abort http memcached request"); return; } static void ngx_http_memcached_finalize_request(ngx_http_request_t *r, ngx_int_t rc) { ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "finalize http memcached request"); return; } static void * ngx_http_memcached_create_loc_conf(ngx_conf_t *cf) { ngx_http_memcached_loc_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_memcached_loc_conf_t)); if (conf == NULL) { return NULL; } /* * set by ngx_pcalloc(): * * conf->upstream.bufs.num = 0; * conf->upstream.next_upstream = 0; * conf->upstream.temp_path = NULL; * conf->upstream.uri = { 0, NULL }; * conf->upstream.location = NULL; */ conf->upstream.local = NGX_CONF_UNSET_PTR; conf->upstream.next_upstream_tries = NGX_CONF_UNSET_UINT; conf->upstream.connect_timeout = NGX_CONF_UNSET_MSEC; conf->upstream.send_timeout = NGX_CONF_UNSET_MSEC; conf->upstream.read_timeout = NGX_CONF_UNSET_MSEC; conf->upstream.next_upstream_timeout = NGX_CONF_UNSET_MSEC; conf->upstream.buffer_size = NGX_CONF_UNSET_SIZE; /* the hardcoded values */ conf->upstream.cyclic_temp_file = 0; conf->upstream.buffering = 0; conf->upstream.ignore_client_abort = 0; conf->upstream.send_lowat = 0; conf->upstream.bufs.num = 0; conf->upstream.busy_buffers_size = 0; conf->upstream.max_temp_file_size = 0; conf->upstream.temp_file_write_size = 0; conf->upstream.intercept_errors = 1; conf->upstream.intercept_404 = 1; conf->upstream.pass_request_headers = 0; conf->upstream.pass_request_body = 0; conf->upstream.force_ranges = 1; conf->index = NGX_CONF_UNSET; conf->gzip_flag = NGX_CONF_UNSET_UINT; return conf; } static char * ngx_http_memcached_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_http_memcached_loc_conf_t *prev = parent; ngx_http_memcached_loc_conf_t *conf = child; ngx_conf_merge_ptr_value(conf->upstream.local, prev->upstream.local, NULL); ngx_conf_merge_uint_value(conf->upstream.next_upstream_tries, prev->upstream.next_upstream_tries, 0); ngx_conf_merge_msec_value(conf->upstream.connect_timeout, prev->upstream.connect_timeout, 60000); ngx_conf_merge_msec_value(conf->upstream.send_timeout, prev->upstream.send_timeout, 60000); ngx_conf_merge_msec_value(conf->upstream.read_timeout, prev->upstream.read_timeout, 60000); ngx_conf_merge_msec_value(conf->upstream.next_upstream_timeout, prev->upstream.next_upstream_timeout, 0); ngx_conf_merge_size_value(conf->upstream.buffer_size, prev->upstream.buffer_size, (size_t) ngx_pagesize); ngx_conf_merge_bitmask_value(conf->upstream.next_upstream, prev->upstream.next_upstream, (NGX_CONF_BITMASK_SET |NGX_HTTP_UPSTREAM_FT_ERROR |NGX_HTTP_UPSTREAM_FT_TIMEOUT)); if (conf->upstream.next_upstream & NGX_HTTP_UPSTREAM_FT_OFF) { conf->upstream.next_upstream = NGX_CONF_BITMASK_SET |NGX_HTTP_UPSTREAM_FT_OFF; } if (conf->upstream.upstream == NULL) { conf->upstream.upstream = prev->upstream.upstream; } if (conf->index == NGX_CONF_UNSET) { conf->index = prev->index; } ngx_conf_merge_uint_value(conf->gzip_flag, prev->gzip_flag, 0); return NGX_CONF_OK; } static char * ngx_http_memcached_pass(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_memcached_loc_conf_t *mlcf = conf; ngx_str_t *value; ngx_url_t u; ngx_http_core_loc_conf_t *clcf; if (mlcf->upstream.upstream) { return "is duplicate"; } value = cf->args->elts; ngx_memzero(&u, sizeof(ngx_url_t)); u.url = value[1]; u.no_resolve = 1; mlcf->upstream.upstream = ngx_http_upstream_add(cf, &u, 0); if (mlcf->upstream.upstream == NULL) { return NGX_CONF_ERROR; } clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module); clcf->handler = ngx_http_memcached_handler; if (clcf->name.data[clcf->name.len - 1] == '/') { clcf->auto_redirect = 1; } mlcf->index = ngx_http_get_variable_index(cf, &ngx_http_memcached_key); if (mlcf->index == NGX_ERROR) { return NGX_CONF_ERROR; } return NGX_CONF_OK; }