view src/stream/ngx_stream_upstream.c @ 6435:d1c791479bbb

Stream: post first read events from client and upstream. The main proxy function ngx_stream_proxy_process() can terminate the stream session. The code, following it, should check its return code to make sure the session still exists. This happens in client and upstream initialization functions. Swapping ngx_stream_proxy_process() call with the code, that follows it, leaves the same problem vice versa. In future ngx_stream_proxy_process() will call ngx_stream_proxy_next_upstream() making it too complicated to know if stream session still exists after this call. Now ngx_stream_proxy_process() is called from posted event handlers in both places with no code following it. The posted event is automatically removed once session is terminated.
author Roman Arutyunyan <arut@nginx.com>
date Tue, 15 Mar 2016 15:55:23 +0300
parents cf5e822cf470
children 78fc2dce69e7
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_stream.h>


static char *ngx_stream_upstream(ngx_conf_t *cf, ngx_command_t *cmd,
    void *dummy);
static char *ngx_stream_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static void *ngx_stream_upstream_create_main_conf(ngx_conf_t *cf);
static char *ngx_stream_upstream_init_main_conf(ngx_conf_t *cf, void *conf);


static ngx_command_t  ngx_stream_upstream_commands[] = {

    { ngx_string("upstream"),
      NGX_STREAM_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_TAKE1,
      ngx_stream_upstream,
      0,
      0,
      NULL },

    { ngx_string("server"),
      NGX_STREAM_UPS_CONF|NGX_CONF_1MORE,
      ngx_stream_upstream_server,
      NGX_STREAM_SRV_CONF_OFFSET,
      0,
      NULL },

      ngx_null_command
};


static ngx_stream_module_t  ngx_stream_upstream_module_ctx = {
    NULL,                                  /* postconfiguration */

    ngx_stream_upstream_create_main_conf,  /* create main configuration */
    ngx_stream_upstream_init_main_conf,    /* init main configuration */

    NULL,                                  /* create server configuration */
    NULL,                                  /* merge server configuration */
};


ngx_module_t  ngx_stream_upstream_module = {
    NGX_MODULE_V1,
    &ngx_stream_upstream_module_ctx,       /* module context */
    ngx_stream_upstream_commands,          /* module directives */
    NGX_STREAM_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 char *
ngx_stream_upstream(ngx_conf_t *cf, ngx_command_t *cmd, void *dummy)
{
    char                            *rv;
    void                            *mconf;
    ngx_str_t                       *value;
    ngx_url_t                        u;
    ngx_uint_t                       m;
    ngx_conf_t                       pcf;
    ngx_stream_module_t             *module;
    ngx_stream_conf_ctx_t           *ctx, *stream_ctx;
    ngx_stream_upstream_srv_conf_t  *uscf;

    ngx_memzero(&u, sizeof(ngx_url_t));

    value = cf->args->elts;
    u.host = value[1];
    u.no_resolve = 1;
    u.no_port = 1;

    uscf = ngx_stream_upstream_add(cf, &u, NGX_STREAM_UPSTREAM_CREATE
                                           |NGX_STREAM_UPSTREAM_WEIGHT
                                           |NGX_STREAM_UPSTREAM_MAX_FAILS
                                           |NGX_STREAM_UPSTREAM_FAIL_TIMEOUT
                                           |NGX_STREAM_UPSTREAM_DOWN
                                           |NGX_STREAM_UPSTREAM_BACKUP);
    if (uscf == NULL) {
        return NGX_CONF_ERROR;
    }


    ctx = ngx_pcalloc(cf->pool, sizeof(ngx_stream_conf_ctx_t));
    if (ctx == NULL) {
        return NGX_CONF_ERROR;
    }

    stream_ctx = cf->ctx;
    ctx->main_conf = stream_ctx->main_conf;

    /* the upstream{}'s srv_conf */

    ctx->srv_conf = ngx_pcalloc(cf->pool,
                                sizeof(void *) * ngx_stream_max_module);
    if (ctx->srv_conf == NULL) {
        return NGX_CONF_ERROR;
    }

    ctx->srv_conf[ngx_stream_upstream_module.ctx_index] = uscf;

    uscf->srv_conf = ctx->srv_conf;

    for (m = 0; cf->cycle->modules[m]; m++) {
        if (cf->cycle->modules[m]->type != NGX_STREAM_MODULE) {
            continue;
        }

        module = cf->cycle->modules[m]->ctx;

        if (module->create_srv_conf) {
            mconf = module->create_srv_conf(cf);
            if (mconf == NULL) {
                return NGX_CONF_ERROR;
            }

            ctx->srv_conf[cf->cycle->modules[m]->ctx_index] = mconf;
        }
    }

    uscf->servers = ngx_array_create(cf->pool, 4,
                                     sizeof(ngx_stream_upstream_server_t));
    if (uscf->servers == NULL) {
        return NGX_CONF_ERROR;
    }


    /* parse inside upstream{} */

    pcf = *cf;
    cf->ctx = ctx;
    cf->cmd_type = NGX_STREAM_UPS_CONF;

    rv = ngx_conf_parse(cf, NULL);

    *cf = pcf;

    if (rv != NGX_CONF_OK) {
        return rv;
    }

    if (uscf->servers->nelts == 0) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "no servers are inside upstream");
        return NGX_CONF_ERROR;
    }

    return rv;
}


static char *
ngx_stream_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_stream_upstream_srv_conf_t  *uscf = conf;

    time_t                         fail_timeout;
    ngx_str_t                     *value, s;
    ngx_url_t                      u;
    ngx_int_t                      weight, max_fails;
    ngx_uint_t                     i;
    ngx_stream_upstream_server_t  *us;

    us = ngx_array_push(uscf->servers);
    if (us == NULL) {
        return NGX_CONF_ERROR;
    }

    ngx_memzero(us, sizeof(ngx_stream_upstream_server_t));

    value = cf->args->elts;

    weight = 1;
    max_fails = 1;
    fail_timeout = 10;

    for (i = 2; i < cf->args->nelts; i++) {

        if (ngx_strncmp(value[i].data, "weight=", 7) == 0) {

            if (!(uscf->flags & NGX_STREAM_UPSTREAM_WEIGHT)) {
                goto not_supported;
            }

            weight = ngx_atoi(&value[i].data[7], value[i].len - 7);

            if (weight == NGX_ERROR || weight == 0) {
                goto invalid;
            }

            continue;
        }

        if (ngx_strncmp(value[i].data, "max_fails=", 10) == 0) {

            if (!(uscf->flags & NGX_STREAM_UPSTREAM_MAX_FAILS)) {
                goto not_supported;
            }

            max_fails = ngx_atoi(&value[i].data[10], value[i].len - 10);

            if (max_fails == NGX_ERROR) {
                goto invalid;
            }

            continue;
        }

        if (ngx_strncmp(value[i].data, "fail_timeout=", 13) == 0) {

            if (!(uscf->flags & NGX_STREAM_UPSTREAM_FAIL_TIMEOUT)) {
                goto not_supported;
            }

            s.len = value[i].len - 13;
            s.data = &value[i].data[13];

            fail_timeout = ngx_parse_time(&s, 1);

            if (fail_timeout == (time_t) NGX_ERROR) {
                goto invalid;
            }

            continue;
        }

        if (ngx_strcmp(value[i].data, "backup") == 0) {

            if (!(uscf->flags & NGX_STREAM_UPSTREAM_BACKUP)) {
                goto not_supported;
            }

            us->backup = 1;

            continue;
        }

        if (ngx_strcmp(value[i].data, "down") == 0) {

            if (!(uscf->flags & NGX_STREAM_UPSTREAM_DOWN)) {
                goto not_supported;
            }

            us->down = 1;

            continue;
        }

        goto invalid;
    }

    ngx_memzero(&u, sizeof(ngx_url_t));

    u.url = value[1];

    if (ngx_parse_url(cf->pool, &u) != NGX_OK) {
        if (u.err) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "%s in upstream \"%V\"", u.err, &u.url);
        }

        return NGX_CONF_ERROR;
    }

    if (u.no_port) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "no port in upstream \"%V\"", &u.url);
        return NGX_CONF_ERROR;
    }

    us->name = u.url;
    us->addrs = u.addrs;
    us->naddrs = u.naddrs;
    us->weight = weight;
    us->max_fails = max_fails;
    us->fail_timeout = fail_timeout;

    return NGX_CONF_OK;

invalid:

    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                       "invalid parameter \"%V\"", &value[i]);

    return NGX_CONF_ERROR;

not_supported:

    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                       "balancing method does not support parameter \"%V\"",
                       &value[i]);

    return NGX_CONF_ERROR;
}


ngx_stream_upstream_srv_conf_t *
ngx_stream_upstream_add(ngx_conf_t *cf, ngx_url_t *u, ngx_uint_t flags)
{
    ngx_uint_t                        i;
    ngx_stream_upstream_server_t     *us;
    ngx_stream_upstream_srv_conf_t   *uscf, **uscfp;
    ngx_stream_upstream_main_conf_t  *umcf;

    if (!(flags & NGX_STREAM_UPSTREAM_CREATE)) {

        if (ngx_parse_url(cf->pool, u) != NGX_OK) {
            if (u->err) {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                   "%s in upstream \"%V\"", u->err, &u->url);
            }

            return NULL;
        }
    }

    umcf = ngx_stream_conf_get_module_main_conf(cf, ngx_stream_upstream_module);

    uscfp = umcf->upstreams.elts;

    for (i = 0; i < umcf->upstreams.nelts; i++) {

        if (uscfp[i]->host.len != u->host.len
            || ngx_strncasecmp(uscfp[i]->host.data, u->host.data, u->host.len)
               != 0)
        {
            continue;
        }

        if ((flags & NGX_STREAM_UPSTREAM_CREATE)
             && (uscfp[i]->flags & NGX_STREAM_UPSTREAM_CREATE))
        {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "duplicate upstream \"%V\"", &u->host);
            return NULL;
        }

        if ((uscfp[i]->flags & NGX_STREAM_UPSTREAM_CREATE) && !u->no_port) {
            ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
                               "upstream \"%V\" may not have port %d",
                               &u->host, u->port);
            return NULL;
        }

        if ((flags & NGX_STREAM_UPSTREAM_CREATE) && !uscfp[i]->no_port) {
            ngx_log_error(NGX_LOG_WARN, cf->log, 0,
                          "upstream \"%V\" may not have port %d in %s:%ui",
                          &u->host, uscfp[i]->port,
                          uscfp[i]->file_name, uscfp[i]->line);
            return NULL;
        }

        if (uscfp[i]->port != u->port) {
            continue;
        }

        if (flags & NGX_STREAM_UPSTREAM_CREATE) {
            uscfp[i]->flags = flags;
        }

        return uscfp[i];
    }

    uscf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_upstream_srv_conf_t));
    if (uscf == NULL) {
        return NULL;
    }

    uscf->flags = flags;
    uscf->host = u->host;
    uscf->file_name = cf->conf_file->file.name.data;
    uscf->line = cf->conf_file->line;
    uscf->port = u->port;
    uscf->no_port = u->no_port;

    if (u->naddrs == 1) {
        uscf->servers = ngx_array_create(cf->pool, 1,
                                         sizeof(ngx_stream_upstream_server_t));
        if (uscf->servers == NULL) {
            return NULL;
        }

        us = ngx_array_push(uscf->servers);
        if (us == NULL) {
            return NULL;
        }

        ngx_memzero(us, sizeof(ngx_stream_upstream_server_t));

        us->addrs = u->addrs;
        us->naddrs = 1;
    }

    uscfp = ngx_array_push(&umcf->upstreams);
    if (uscfp == NULL) {
        return NULL;
    }

    *uscfp = uscf;

    return uscf;
}


static void *
ngx_stream_upstream_create_main_conf(ngx_conf_t *cf)
{
    ngx_stream_upstream_main_conf_t  *umcf;

    umcf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_upstream_main_conf_t));
    if (umcf == NULL) {
        return NULL;
    }

    if (ngx_array_init(&umcf->upstreams, cf->pool, 4,
                       sizeof(ngx_stream_upstream_srv_conf_t *))
        != NGX_OK)
    {
        return NULL;
    }

    return umcf;
}


static char *
ngx_stream_upstream_init_main_conf(ngx_conf_t *cf, void *conf)
{
    ngx_stream_upstream_main_conf_t *umcf = conf;

    ngx_uint_t                        i;
    ngx_stream_upstream_init_pt       init;
    ngx_stream_upstream_srv_conf_t  **uscfp;

    uscfp = umcf->upstreams.elts;

    for (i = 0; i < umcf->upstreams.nelts; i++) {

        init = uscfp[i]->peer.init_upstream
                                         ? uscfp[i]->peer.init_upstream
                                         : ngx_stream_upstream_init_round_robin;

        if (init(cf, uscfp[i]) != NGX_OK) {
            return NGX_CONF_ERROR;
        }
    }

    return NGX_CONF_OK;
}