for #319, support minimal query api

@@ -1468,6 +1468,24 @@ int SrsConfig::persistence()
     return ret;
 }
 
+int SrsConfig::minimal_to_json(SrsAmf0Object* obj)
+{
+    int ret = ERROR_SUCCESS;
+    
+    for (int i = 0; i < (int)root->directives.size(); i++) {
+        SrsConfDirective* dir = root->directives.at(i);
+        if (dir->is_vhost()) {
+            continue;
+        }
+        
+        if (dir->name == "listen") {
+            obj->set(dir->name, dir->dumps_args());
+        }
+    }
+    
+    return ret;
+}
+
 int SrsConfig::global_to_json(SrsAmf0Object* obj)
 {
     int ret = ERROR_SUCCESS;

@@ -322,6 +322,10 @@ public:
      */
     virtual int global_to_json(SrsAmf0Object* obj);
     /**
+     * dumps the minimal sections to json.
+     */
+    virtual int minimal_to_json(SrsAmf0Object* obj);
+    /**
      * dumps the vhost section to json.
      */
     virtual int vhost_to_json(SrsConfDirective* vhost, SrsAmf0Object* obj);

@@ -917,6 +917,7 @@ int SrsGoApiRaw::serve_http(ISrsHttpResponseWriter* w, ISrsHttpMessage* r)
     // for rpc=query, to get the configs of server.
     //      @param scope the scope to query for config, it can be:
     //              global, the configs belongs to the root, donot includes any sub directives.
+    //              minimal, the minimal summary of server, for preview stream to got the port serving.
     //              vhost, the configs for specified vhost by @param vhost.
     //      @param vhost the vhost name for @param scope is vhost to query config.
     //              for the default vhost, must be __defaultVhost__
@@ -929,7 +930,7 @@ int SrsGoApiRaw::serve_http(ISrsHttpResponseWriter* w, ISrsHttpMessage* r)
         
         std::string scope = r->query_get("scope");
         std::string vhost = r->query_get("vhost");
-        if (scope.empty() || (scope != "global" && scope != "vhost")) {
+        if (scope.empty() || (scope != "global" && scope != "vhost" && scope != "minimal")) {
             ret = ERROR_SYSTEM_CONFIG_RAW_NOT_ALLOWED;
             srs_error("raw api query invalid scope=%s. ret=%d", scope.c_str(), ret);
             return srs_api_response_code(w, r, ret);
@@ -957,6 +958,15 @@ int SrsGoApiRaw::serve_http(ISrsHttpResponseWriter* w, ISrsHttpMessage* r)
                 srs_error("raw api query vhost failed. ret=%d", ret);
                 return srs_api_response_code(w, r, ret);
             }
+        } else if (scope == "minimal") {
+            SrsAmf0Object* data = SrsAmf0Any::object();
+            obj->set("minimal", data);
+            
+            // query minimal scope.
+            if ((ret = _srs_config->minimal_to_json(data)) != ERROR_SUCCESS) {
+                srs_error("raw api query global failed. ret=%d", ret);
+                return srs_api_response_code(w, r, ret);
+            }
         } else {
             SrsAmf0Object* data = SrsAmf0Any::object();
             obj->set("global", data);