Forward: support config full rtmp url forward to other server (#2799)

* Forward: add backend config and demo server for dynamic create forwarder to other server.(#1342)

* Forward: if call forward backend failed, then return directly.

* Forward: add API description and change return value format.

* Forward: add backend conf file and wrapper function for backend service.

* Forward: add backend comment in full.conf and update forward.backend.conf.

* Forward: rename backend param and add comment tips.

trunk/conf/forward.backend.conf

@@ -0,0 +1,15 @@
+# the config for srs to forward to slave service
+# @see https://github.com/ossrs/srs/wiki/v5_CN_SampleForward
+# @see full.conf for detail config.
+
+listen              1935;
+max_connections     1000;
+pid                 ./objs/srs.backend.pid;
+daemon              off;
+srs_log_tank        console;
+vhost __defaultVhost__ {
+    forward {
+        enabled on;
+        backend http://127.0.0.1:8085/api/v1/forward;
+    }
+}

trunk/conf/full.conf

@@ -669,6 +669,37 @@ vhost same.vhost.forward.srs.com {
         # active-active for cdn to build high available fault tolerance system.
         # format: {ip}:{port} {ip_N}:{port_N}
         destination 127.0.0.1:1936 127.0.0.1:1937;
+
+        # when client(encoder) publish to vhost/app/stream, call the hook in creating backend forwarder.
+        # the request in the POST data string is a object encode by json:
+        #       {
+        #           "action": "on_forward",
+        #           "server_id": "vid-k21d7y2",
+        #           "client_id": "9o7g1330",
+        #           "ip": "127.0.0.1",
+        #           "vhost": "__defaultVhost__",
+        #           "app": "live",
+        #           "tcUrl": "rtmp://127.0.0.1:1935/live",
+        #           "stream": "livestream",
+        #           "param": ""
+        #       }
+        # if valid, the hook must return HTTP code 200(Status OK) and response
+        # an int value specifies the error code(0 corresponding to success):
+        #       {
+        #          "code": 0,
+        #          "data": {
+        #              "urls":[
+        #                 "rtmp://127.0.0.1:19350/test/teststream"
+        #              ]
+        #          }
+        #       }
+        # PS: you can transform params to backend service, such as:
+        #       { "param": "?forward=rtmp://127.0.0.1:19351/test/livestream" }
+        #     then backend return forward's url in response.
+        # if backend return empty urls, destanition is still disabled.
+        # only support one api hook, format:
+        #       backend http://xxx/api0
+        backend http://127.0.0.1:8085/api/v1/forward;
     }
 }
 

trunk/research/api-server/server.py

@@ -805,6 +805,86 @@ class RESTSnapshots(object):
     def OPTIONS(self, *args, **kwargs):
         enable_crossdomain()
 
+'''
+handle the forward requests: dynamic forward url.
+'''
+class RESTForward(object):
+    exposed = True
+
+    def __init__(self):
+        self.__forwards = []
+
+    def GET(self):
+        enable_crossdomain()
+
+        forwards = {}
+        return json.dumps(forwards)
+
+    '''
+    for SRS hook: on_forward
+    on_forward:
+        when srs reap a dvr file, call the hook,
+        the request in the POST data string is a object encode by json:
+              {
+                  "action": "on_forward",
+                  "server_id": "server_test",
+                  "client_id": 1985,
+                  "ip": "192.168.1.10",
+                  "vhost": "video.test.com",
+                  "app": "live",
+                  "tcUrl": "rtmp://video.test.com/live?key=d2fa801d08e3f90ed1e1670e6e52651a",
+                  "stream": "livestream",
+                  "param":"?token=xxx&salt=yyy"
+              }
+    if valid, the hook must return HTTP code 200(Stauts OK) and response
+    an int value specifies the error code(0 corresponding to success):
+          0
+    '''
+    def POST(self):
+        enable_crossdomain()
+
+        # return the error code in str
+        code = Error.success
+
+        req = cherrypy.request.body.read()
+        trace("post to forwards, req=%s"%(req))
+        try:
+            json_req = json.loads(req)
+        except Exception, ex:
+            code = Error.system_parse_json
+            trace("parse the request to json failed, req=%s, ex=%s, code=%s"%(req, ex, code))
+            return json.dumps({"code": int(code), "data": None})
+
+        action = json_req["action"]
+        if action == "on_forward":
+            return self.__on_forward(json_req)
+        else:
+            trace("invalid request action: %s"%(json_req["action"]))
+            code = Error.request_invalid_action
+
+        return json.dumps({"code": int(code), "data": None})
+
+    def OPTIONS(self, *args, **kwargs):
+        enable_crossdomain()
+
+    def __on_forward(self, req):
+        code = Error.success
+
+        trace("srs %s: client id=%s, ip=%s, vhost=%s, app=%s, tcUrl=%s, stream=%s, param=%s"%(
+            req["action"], req["client_id"], req["ip"], req["vhost"], req["app"], req["tcUrl"], req["stream"], req["param"]
+        ))
+
+        '''
+        backend service config description:
+            support multiple rtmp urls(custom addresses or third-party cdn service),
+            url's host is slave service.
+        For example:
+            ["rtmp://127.0.0.1:19350/test/teststream", "rtmp://127.0.0.1:19350/test/teststream?token=xxxx"]
+        '''
+        forwards = ["rtmp://127.0.0.1:19350/test/teststream"]
+
+        return json.dumps({"code": int(code), "data": {"urls": forwards}})
+
 # HTTP RESTful path.
 class Root(object):
     exposed = True
@@ -846,6 +926,7 @@ class V1(object):
         self.chats = RESTChats()
         self.servers = RESTServers()
         self.snapshots = RESTSnapshots()
+        self.forward = RESTForward()
     def GET(self):
         enable_crossdomain();
         return json.dumps({"code":Error.success, "urls":{

trunk/src/app/srs_app_config.cpp

@@ -2825,7 +2825,7 @@ srs_error_t SrsConfig::check_normal_config()
             } else if (n == "forward") {
                 for (int j = 0; j < (int)conf->directives.size(); j++) {
                     string m = conf->at(j)->name;
-                    if (m != "enabled" && m != "destination") {
+                    if (m != "enabled" && m != "destination" && m != "backend") {
                         return srs_error_new(ERROR_SYSTEM_CONFIG_INVALID, "illegal vhost.forward.%s of %s", m.c_str(), vhost->arg0().c_str());
                     }
                 }
@@ -4635,6 +4635,21 @@ SrsConfDirective* SrsConfig::get_forwards(string vhost)
     return conf->get("destination");
 }
 
+SrsConfDirective* SrsConfig::get_forward_backend(string vhost)
+{
+    SrsConfDirective* conf = get_vhost(vhost);
+    if (!conf) {
+        return NULL;
+    }
+    
+    conf = conf->get("forward");
+    if (!conf) {
+        return NULL;
+    }
+    
+    return conf->get("backend");
+}
+
 SrsConfDirective* SrsConfig::get_vhost_http_hooks(string vhost)
 {
     SrsConfDirective* conf = get_vhost(vhost);

trunk/src/app/srs_app_config.hpp

@@ -624,6 +624,8 @@ public:
     virtual bool get_forward_enabled(SrsConfDirective* vhost);
     // Get the forward directive of vhost.
     virtual SrsConfDirective* get_forwards(std::string vhost);
+    // Get the forward directive of backend.
+    virtual SrsConfDirective* get_forward_backend(std::string vhost);
 
 public:
     // Whether the srt sevice enabled

trunk/src/app/srs_app_forward.cpp

@@ -52,6 +52,8 @@ SrsForwarder::~SrsForwarder()
     
     srs_freep(sh_video);
     srs_freep(sh_audio);
+    
+    srs_freep(req);
 }
 
 srs_error_t SrsForwarder::initialize(SrsRequest* r, string ep)
@@ -60,7 +62,7 @@ srs_error_t SrsForwarder::initialize(SrsRequest* r, string ep)
     
     // it's ok to use the request object,
     // SrsLiveSource already copy it and never delete it.
-    req = r;
+    req = r->copy();
     
     // the ep(endpoint) to forward to
     ep_forward = ep;

trunk/src/app/srs_app_http_hooks.cpp

@@ -482,6 +482,76 @@ srs_error_t SrsHttpHooks::discover_co_workers(string url, string& host, int& por
     return err;
 }
 
+srs_error_t SrsHttpHooks::on_forward_backend(string url, SrsRequest* req, std::vector<std::string>& rtmp_urls)
+{
+    srs_error_t err = srs_success;
+
+    SrsContextId cid = _srs_context->get_id();
+
+    SrsStatistic* stat = SrsStatistic::instance();
+
+    SrsJsonObject* obj = SrsJsonAny::object();
+    SrsAutoFree(SrsJsonObject, obj);
+
+    obj->set("action", SrsJsonAny::str("on_forward"));
+    obj->set("server_id", SrsJsonAny::str(stat->server_id().c_str()));
+    obj->set("client_id", SrsJsonAny::str(cid.c_str()));
+    obj->set("ip", SrsJsonAny::str(req->ip.c_str()));
+    obj->set("vhost", SrsJsonAny::str(req->vhost.c_str()));
+    obj->set("app", SrsJsonAny::str(req->app.c_str()));
+    obj->set("tcUrl", SrsJsonAny::str(req->tcUrl.c_str()));
+    obj->set("stream", SrsJsonAny::str(req->stream.c_str()));
+    obj->set("param", SrsJsonAny::str(req->param.c_str()));
+
+    std::string data = obj->dumps();
+    std::string res;
+    int status_code;
+
+    SrsHttpClient http;
+    if ((err = do_post(&http, url, data, status_code, res)) != srs_success) {
+        return srs_error_wrap(err, "http: on_forward_backend failed, client_id=%s, url=%s, request=%s, response=%s, code=%d",
+            cid.c_str(), url.c_str(), data.c_str(), res.c_str(), status_code);
+    }
+
+    // parse string res to json.
+    SrsJsonAny* info = SrsJsonAny::loads(res);
+    if (!info) {
+        return srs_error_new(ERROR_SYSTEM_FORWARD_LOOP, "load json from %s", res.c_str());
+    }
+    SrsAutoFree(SrsJsonAny, info);
+
+    // response error code in string.
+    if (!info->is_object()) {
+        return srs_error_new(ERROR_SYSTEM_FORWARD_LOOP, "response %s", res.c_str());
+    }
+
+    SrsJsonAny* prop = NULL;
+    // response standard object, format in json: {}
+    SrsJsonObject* res_info = info->to_object();
+    if ((prop = res_info->ensure_property_object("data")) == NULL) {
+        return srs_error_new(ERROR_SYSTEM_FORWARD_LOOP, "parse data %s", res.c_str());
+    }
+
+    SrsJsonObject* p = prop->to_object();
+    if ((prop = p->ensure_property_array("urls")) == NULL) {
+        return srs_error_new(ERROR_SYSTEM_FORWARD_LOOP, "parse urls %s", res.c_str());
+    }
+
+    SrsJsonArray* urls = prop->to_array();
+    for (int i = 0; i < urls->count(); i++) {
+        prop = urls->at(i);
+        string rtmp_url = prop->to_str();
+        if (!rtmp_url.empty()) {
+            rtmp_urls.push_back(rtmp_url);
+        }
+    }
+
+    srs_trace("http: on_forward_backend ok, client_id=%s, url=%s, request=%s, response=%s",
+        cid.c_str(), url.c_str(), data.c_str(), res.c_str());
+
+    return err;
+}
+
 srs_error_t SrsHttpHooks::do_post(SrsHttpClient* hc, std::string url, std::string req, int& code, string& res)
 {
     srs_error_t err = srs_success;

trunk/src/app/srs_app_http_hooks.hpp

@@ -10,6 +10,7 @@
 #include <srs_core.hpp>
 
 #include <string>
+#include <vector>
 
 class SrsHttpUri;
 class SrsStSocket;
@@ -79,6 +80,10 @@ public:
     static srs_error_t on_hls_notify(SrsContextId cid, std::string url, SrsRequest* req, std::string ts_url, int nb_notify);
     // Discover co-workers for origin cluster.
     static srs_error_t discover_co_workers(std::string url, std::string& host, int& port);
+    // The on_forward_backend hook, when publish stream start to forward
+    // @param url the api server url, to valid the client.
+    //         ignore if empty.
+    static srs_error_t on_forward_backend(std::string url, SrsRequest* req, std::vector<std::string>& rtmp_urls);
 private:
     static srs_error_t do_post(SrsHttpClient* hc, std::string url, std::string req, int& code, std::string& res);
 };

trunk/src/app/srs_app_source.cpp

@@ -34,6 +34,7 @@ using namespace std;
 #include <srs_app_dash.hpp>
 #include <srs_protocol_format.hpp>
 #include <srs_app_rtc_source.hpp>
+#include <srs_app_http_hooks.hpp>
 
 #define CONST_MAX_JITTER_MS         250
 #define CONST_MAX_JITTER_MS_NEG         -250
@@ -807,7 +808,7 @@ SrsSharedPtrMessage* SrsMixQueue::pop()
 SrsOriginHub::SrsOriginHub()
 {
     source = NULL;
-    req = NULL;
+    req_ = NULL;
     is_active = false;
     
     hls = new SrsHls();
@@ -851,22 +852,22 @@ srs_error_t SrsOriginHub::initialize(SrsLiveSource* s, SrsRequest* r)
 {
     srs_error_t err = srs_success;
     
-    req = r;
+    req_ = r;
     source = s;
     
     if ((err = format->initialize()) != srs_success) {
         return srs_error_wrap(err, "format initialize");
     }
     
-    if ((err = hls->initialize(this, req)) != srs_success) {
+    if ((err = hls->initialize(this, req_)) != srs_success) {
         return srs_error_wrap(err, "hls initialize");
     }
     
-    if ((err = dash->initialize(this, req)) != srs_success) {
+    if ((err = dash->initialize(this, req_)) != srs_success) {
         return srs_error_wrap(err, "dash initialize");
     }
     
-    if ((err = dvr->initialize(this, req)) != srs_success) {
+    if ((err = dvr->initialize(this, req_)) != srs_success) {
         return srs_error_wrap(err, "dvr initialize");
     }
     
@@ -952,7 +953,7 @@ srs_error_t SrsOriginHub::on_audio(SrsSharedPtrMessage* shared_audio)
         
         // when got audio stream info.
         SrsStatistic* stat = SrsStatistic::instance();
-        if ((err = stat->on_audio_info(req, SrsAudioCodecIdAAC, c->sound_rate, c->sound_type, c->aac_object)) != srs_success) {
+        if ((err = stat->on_audio_info(req_, SrsAudioCodecIdAAC, c->sound_rate, c->sound_type, c->aac_object)) != srs_success) {
             return srs_error_wrap(err, "stat audio");
         }
         
@@ -966,7 +967,7 @@ srs_error_t SrsOriginHub::on_audio(SrsSharedPtrMessage* shared_audio)
     if ((err = hls->on_audio(msg, format)) != srs_success) {
         // apply the error strategy for hls.
         // @see https://github.com/ossrs/srs/issues/264
-        std::string hls_error_strategy = _srs_config->get_hls_on_error(req->vhost);
+        std::string hls_error_strategy = _srs_config->get_hls_on_error(req_->vhost);
         if (srs_config_hls_is_on_error_ignore(hls_error_strategy)) {
             srs_warn("hls: ignore audio error %s", srs_error_desc(err).c_str());
             hls->on_unpublish();
@@ -1025,7 +1026,7 @@ srs_error_t SrsOriginHub::on_video(SrsSharedPtrMessage* shared_video, bool is_se
     // user can disable the sps parse to workaround when parse sps failed.
     // @see https://github.com/ossrs/srs/issues/474
     if (is_sequence_header) {
-        format->avc_parse_sps = _srs_config->get_parse_sps(req->vhost);
+        format->avc_parse_sps = _srs_config->get_parse_sps(req_->vhost);
     }
     
     if ((err = format->on_video(msg)) != srs_success) {
@@ -1046,7 +1047,7 @@ srs_error_t SrsOriginHub::on_video(SrsSharedPtrMessage* shared_video, bool is_se
         
         // when got video stream info.
         SrsStatistic* stat = SrsStatistic::instance();
-        if ((err = stat->on_video_info(req, SrsVideoCodecIdAVC, c->avc_profile, c->avc_level, c->width, c->height)) != srs_success) {
+        if ((err = stat->on_video_info(req_, SrsVideoCodecIdAVC, c->avc_profile, c->avc_level, c->width, c->height)) != srs_success) {
             return srs_error_wrap(err, "stat video");
         }
         
@@ -1066,7 +1067,7 @@ srs_error_t SrsOriginHub::on_video(SrsSharedPtrMessage* shared_video, bool is_se
         // TODO: We should support more strategies.
         // apply the error strategy for hls.
         // @see https://github.com/ossrs/srs/issues/264
-        std::string hls_error_strategy = _srs_config->get_hls_on_error(req->vhost);
+        std::string hls_error_strategy = _srs_config->get_hls_on_error(req_->vhost);
         if (srs_config_hls_is_on_error_ignore(hls_error_strategy)) {
             srs_warn("hls: ignore video error %s", srs_error_desc(err).c_str());
             hls->on_unpublish();
@@ -1126,7 +1127,7 @@ srs_error_t SrsOriginHub::on_publish()
     }
     
     // TODO: FIXME: use initialize to set req.
-    if ((err = encoder->on_publish(req)) != srs_success) {
+    if ((err = encoder->on_publish(req_)) != srs_success) {
         return srs_error_wrap(err, "encoder publish");
     }
 
@@ -1139,7 +1140,7 @@ srs_error_t SrsOriginHub::on_publish()
     }
     
     // @see https://github.com/ossrs/srs/issues/1613#issuecomment-961657927
-    if ((err = dvr->on_publish(req)) != srs_success) {
+    if ((err = dvr->on_publish(req_)) != srs_success) {
         return srs_error_wrap(err, "dvr publish");
     }
     
@@ -1151,7 +1152,7 @@ srs_error_t SrsOriginHub::on_publish()
 #endif
     
     // TODO: FIXME: use initialize to set req.
-    if ((err = ng_exec->on_publish(req)) != srs_success) {
+    if ((err = ng_exec->on_publish(req_)) != srs_success) {
         return srs_error_wrap(err, "exec publish");
     }
     
@@ -1236,7 +1237,7 @@ srs_error_t SrsOriginHub::on_reload_vhost_forward(string vhost)
 {
     srs_error_t err = srs_success;
     
-    if (req->vhost != vhost) {
+    if (req_->vhost != vhost) {
         return err;
     }
     
@@ -1263,7 +1264,7 @@ srs_error_t SrsOriginHub::on_reload_vhost_dash(string vhost)
 {
     srs_error_t err = srs_success;
     
-    if (req->vhost != vhost) {
+    if (req_->vhost != vhost) {
         return err;
     }
     
@@ -1305,7 +1306,7 @@ srs_error_t SrsOriginHub::on_reload_vhost_hls(string vhost)
 {
     srs_error_t err = srs_success;
     
-    if (req->vhost != vhost) {
+    if (req_->vhost != vhost) {
         return err;
     }
     
@@ -1355,7 +1356,7 @@ srs_error_t SrsOriginHub::on_reload_vhost_hds(string vhost)
 {
     srs_error_t err = srs_success;
     
-    if (req->vhost != vhost) {
+    if (req_->vhost != vhost) {
         return err;
     }
     
@@ -1382,7 +1383,7 @@ srs_error_t SrsOriginHub::on_reload_vhost_dvr(string vhost)
 {
     srs_error_t err = srs_success;
     
-    if (req->vhost != vhost) {
+    if (req_->vhost != vhost) {
         return err;
     }
     
@@ -1397,12 +1398,12 @@ srs_error_t SrsOriginHub::on_reload_vhost_dvr(string vhost)
     }
     
     // reinitialize the dvr, update plan.
-    if ((err = dvr->initialize(this, req)) != srs_success) {
+    if ((err = dvr->initialize(this, req_)) != srs_success) {
         return srs_error_wrap(err, "reload dvr");
     }
     
     // start to publish by new plan.
-    if ((err = dvr->on_publish(req)) != srs_success) {
+    if ((err = dvr->on_publish(req_)) != srs_success) {
         return srs_error_wrap(err, "dvr publish failed");
     }
     
@@ -1419,7 +1420,7 @@ srs_error_t SrsOriginHub::on_reload_vhost_transcode(string vhost)
 {
     srs_error_t err = srs_success;
     
-    if (req->vhost != vhost) {
+    if (req_->vhost != vhost) {
         return err;
     }
     
@@ -1432,7 +1433,7 @@ srs_error_t SrsOriginHub::on_reload_vhost_transcode(string vhost)
         return err;
     }
     
-    if ((err = encoder->on_publish(req)) != srs_success) {
+    if ((err = encoder->on_publish(req_)) != srs_success) {
         return srs_error_wrap(err, "start encoder failed");
     }
     srs_trace("vhost %s transcode reload success", vhost.c_str());
@@ -1444,7 +1445,7 @@ srs_error_t SrsOriginHub::on_reload_vhost_exec(string vhost)
 {
     srs_error_t err = srs_success;
     
-    if (req->vhost != vhost) {
+    if (req_->vhost != vhost) {
         return err;
     }
     
@@ -1457,7 +1458,7 @@ srs_error_t SrsOriginHub::on_reload_vhost_exec(string vhost)
         return err;
     }
     
-    if ((err = ng_exec->on_publish(req)) != srs_success) {
+    if ((err = ng_exec->on_publish(req_)) != srs_success) {
         return srs_error_wrap(err, "start exec failed");
     }
     srs_trace("vhost %s exec reload success", vhost.c_str());
@@ -1469,11 +1470,24 @@ srs_error_t SrsOriginHub::create_forwarders()
 {
     srs_error_t err = srs_success;
     
-    if (!_srs_config->get_forward_enabled(req->vhost)) {
+    if (!_srs_config->get_forward_enabled(req_->vhost)) {
         return err;
     }
-    
+
-    SrsConfDirective* conf = _srs_config->get_forwards(req->vhost);
+    // For backend config
+    // If backend is enabled and applied, ignore destination.
+    bool applied_backend_server = false;
+    if ((err = create_backend_forwarders(applied_backend_server)) != srs_success) {
+        return srs_error_wrap(err, "create backend applied=%d", applied_backend_server);
+    }
+
+    // Already applied backend server, ignore destination.
+    if (applied_backend_server) {
+        return err;
+    }
+
+    // For destanition config
+    SrsConfDirective* conf = _srs_config->get_forwards(req_->vhost);
     for (int i = 0; conf && i < (int)conf->args.size(); i++) {
         std::string forward_server = conf->args.at(i);
         
@@ -1481,22 +1495,81 @@ srs_error_t SrsOriginHub::create_forwarders()
         forwarders.push_back(forwarder);
         
         // initialize the forwarder with request.
-        if ((err = forwarder->initialize(req, forward_server)) != srs_success) {
+        if ((err = forwarder->initialize(req_, forward_server)) != srs_success) {
             return srs_error_wrap(err, "init forwarder");
         }
 
-        srs_utime_t queue_size = _srs_config->get_queue_length(req->vhost);
+        srs_utime_t queue_size = _srs_config->get_queue_length(req_->vhost);
         forwarder->set_queue_size(queue_size);
         
         if ((err = forwarder->on_publish()) != srs_success) {
             return srs_error_wrap(err, "start forwarder failed, vhost=%s, app=%s, stream=%s, forward-to=%s",
-                req->vhost.c_str(), req->app.c_str(), req->stream.c_str(), forward_server.c_str());
+                req_->vhost.c_str(), req_->app.c_str(), req_->stream.c_str(), forward_server.c_str());
         }
     }
     
     return err;
 }
 
+srs_error_t SrsOriginHub::create_backend_forwarders(bool& applied)
+{
+    srs_error_t err = srs_success;
+
+    // default not configure backend service
+    applied = false;
+
+    SrsConfDirective* conf = _srs_config->get_forward_backend(req_->vhost);
+    if (!conf || conf->arg0().empty()) {
+        return err;
+    }
+
+    // configure backend service
+    applied = true;
+
+    // only get first backend url
+    std::string backend_url = conf->arg0();
+
+    // get urls on forward backend
+    std::vector<std::string> urls;
+    if ((err = SrsHttpHooks::on_forward_backend(backend_url, req_, urls)) != srs_success) {
+        return srs_error_wrap(err, "get forward backend failed, backend=%s", backend_url.c_str());
+    }
+
+    // create forwarders by urls
+    std::vector<std::string>::iterator it;
+    for (it = urls.begin(); it != urls.end(); ++it) {
+        std::string url = *it;
+
+        // create temp Request by url
+        SrsRequest* req = new SrsRequest();
+        SrsAutoFree(SrsRequest, req);
+        srs_parse_rtmp_url(url, req->tcUrl, req->stream);
+        srs_discovery_tc_url(req->tcUrl, req->schema, req->host, req->vhost, req->app, req->stream, req->port, req->param);
+
+        // create forwarder
+        SrsForwarder* forwarder = new SrsForwarder(this);
+        forwarders.push_back(forwarder);
+
+        std::stringstream forward_server;
+        forward_server << req->host << ":" << req->port;
+
+        // initialize the forwarder with request.
+        if ((err = forwarder->initialize(req, forward_server.str())) != srs_success) {
+            return srs_error_wrap(err, "init backend forwarder failed, forward-to=%s", forward_server.str().c_str());
+        }
+
+        srs_utime_t queue_size = _srs_config->get_queue_length(req_->vhost);
+        forwarder->set_queue_size(queue_size);
+
+        if ((err = forwarder->on_publish()) != srs_success) {
+            return srs_error_wrap(err, "start backend forwarder failed, vhost=%s, app=%s, stream=%s, forward-to=%s",
+                req_->vhost.c_str(), req_->app.c_str(), req_->stream.c_str(), forward_server.str().c_str());
+        }
+    }
+
+    return err;
+}
+
 void SrsOriginHub::destroy_forwarders()
 {
     std::vector<SrsForwarder*>::iterator it;

trunk/src/app/srs_app_source.hpp

@@ -310,7 +310,7 @@ class SrsOriginHub : public ISrsReloadHandler
 {
 private:
     SrsLiveSource* source;
-    SrsRequest* req;
+    SrsRequest* req_;
     bool is_active;
 private:
     // The format, codec information.
@@ -375,6 +375,7 @@ public:
     virtual srs_error_t on_reload_vhost_exec(std::string vhost);
 private:
     virtual srs_error_t create_forwarders();
+    virtual srs_error_t create_backend_forwarders(bool& applied);
     virtual void destroy_forwarders();
 };
 

trunk/src/utest/srs_utest_config.cpp

@@ -2994,6 +2994,13 @@ VOID TEST(ConfigMainTest, CheckVhostConfig2)
         EXPECT_EQ(5000000, conf.get_publish_normal_timeout("ossrs.net"));
         EXPECT_FALSE(conf.get_forward_enabled("ossrs.net"));
         EXPECT_TRUE(conf.get_forwards("ossrs.net") == NULL);
+        EXPECT_TRUE(conf.get_forward_backend("ossrs.net") == NULL);
+    }
+
+    if (true) {
+        MockSrsConfig conf;
+        HELPER_ASSERT_SUCCESS(conf.parse(_MIN_OK_CONF "vhost ossrs.net{forward {backend xxx;}}"));
+        EXPECT_TRUE(conf.get_forward_backend("ossrs.net") != NULL);
     }
 
     if (true) {