diff --git a/trunk/conf/full.conf b/trunk/conf/full.conf
index e67931d4f..1d138345a 100644
--- a/trunk/conf/full.conf
+++ b/trunk/conf/full.conf
@@ -109,6 +109,9 @@ http_api {
     # the http api port
     # default: 1985
     listen          1985;
+    # whether enable crossdomain request.
+    # default: on
+    crossdomain     on;
 }
 # embeded http server in srs.
 # the http streaming config, for HLS/HDS/DASH/HTTPProgressive
@@ -286,6 +289,31 @@ vhost dvr.srs.com {
         #       segment reap flv when flv duration exceed the specified dvr_duration.
         #       append always append to flv file, never reap it.
         #       api reap flv when api required.
+        # about the api plan, the HTTP api to dvr,
+        #       http url to control dvr, for example, http://dev:1985/api/v1/dvrs
+        #       method=GET
+        #           to query dvrs of server.
+        #           request params, for example ?vhost=__defaultVhost__, where:
+        #               vhost, query all dvr of this vhost.
+        #           response in json, where:
+        #               {code:0, dvrs: [{plan:"api", path:"./objs/nginx/html", 
+        #                   autostart:true, wait_keyframe:true, jitter:"full"
+        #               }]}
+        #       method=POST
+        #           to start dvr of specified vhost.
+        #           request should encode in json, specifies the dvr to create, where:
+        #               {plan:"api", path:"./objs/nginx/html", 
+        #                   autostart:true, wait_keyframe:true, jitter:"full",
+        #                   vhost:"__defaultVhost", callback:"http://dvr/callback"
+        #               }
+        #           response in json, where:
+        #               {code:0}
+        #       method=DELETE, to stop dvr
+        #           to stop dvr of specified vhost.
+        #           request params, for example ?vhost=__defaultVhost__, where:
+        #               vhost, stop all dvr of this vhost.
+        #           response in json, where:
+        #               {code:0}
         # default: session
         dvr_plan        session;
         # the dvr output path.
diff --git a/trunk/src/app/srs_app_config.cpp b/trunk/src/app/srs_app_config.cpp
index dc3614154..2387cb652 100644
--- a/trunk/src/app/srs_app_config.cpp
+++ b/trunk/src/app/srs_app_config.cpp
@@ -1334,7 +1334,7 @@ int SrsConfig::check_config()
         SrsConfDirective* conf = get_http_api();
         for (int i = 0; conf && i < (int)conf->directives.size(); i++) {
             string n = conf->at(i)->name;
-            if (n != "enabled" && n != "listen") {
+            if (n != "enabled" && n != "listen" && n != "crossdomain") {
                 ret = ERROR_SYSTEM_CONFIG_INVALID;
                 srs_error("unsupported http_api directive %s, ret=%d", n.c_str(), ret);
                 return ret;
@@ -3453,6 +3453,22 @@ int SrsConfig::get_http_api_listen()
     return ::atoi(conf->arg0().c_str());
 }
 
+bool SrsConfig::get_http_api_crossdomain()
+{
+    SrsConfDirective* conf = get_http_api();
+    
+    if (!conf) {
+        return SRS_CONF_DEFAULT_HTTP_API_CROSSDOMAIN;
+    }
+    
+    conf = conf->get("crossdomain");
+    if (!conf || conf->arg0().empty()) {
+        return SRS_CONF_DEFAULT_HTTP_API_CROSSDOMAIN;
+    }
+
+    return conf->arg0() != "off";
+}
+
 bool SrsConfig::get_http_stream_enabled()
 {
     SrsConfDirective* conf = get_http_stream();
diff --git a/trunk/src/app/srs_app_config.hpp b/trunk/src/app/srs_app_config.hpp
index 8e149b954..bcef5eac4 100644
--- a/trunk/src/app/srs_app_config.hpp
+++ b/trunk/src/app/srs_app_config.hpp
@@ -79,6 +79,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #define SRS_CONF_DEFAULT_HTTP_STREAM_PORT 8080
 #define SRS_CONF_DEFAULT_HTTP_API_PORT 1985
+#define SRS_CONF_DEFAULT_HTTP_API_CROSSDOMAIN true
 
 #define SRS_CONF_DEFAULT_HTTP_HEAETBEAT_ENABLED false
 #define SRS_CONF_DEFAULT_HTTP_HEAETBEAT_INTERVAL 9.9
@@ -957,6 +958,10 @@ public:
     * get the http api listen port.
     */
     virtual int                 get_http_api_listen();
+    /**
+    * whether enable crossdomain for http api.
+    */
+    virtual bool                get_http_api_crossdomain();
 // http stream section
 private:
     /**
diff --git a/trunk/src/app/srs_app_dvr.cpp b/trunk/src/app/srs_app_dvr.cpp
index 68a662055..97d60d8c5 100644
--- a/trunk/src/app/srs_app_dvr.cpp
+++ b/trunk/src/app/srs_app_dvr.cpp
@@ -40,6 +40,7 @@ using namespace std;
 #include <srs_kernel_file.hpp>
 #include <srs_rtmp_amf0.hpp>
 #include <srs_kernel_stream.hpp>
+#include <srs_app_json.hpp>
 
 // update the flv duration and filesize every this interval in ms.
 #define __SRS_DVR_UPDATE_DURATION_INTERVAL 60000
@@ -665,6 +666,8 @@ SrsDvrPlan* SrsDvrPlan::create_plan(string vhost)
         return new SrsDvrSessionPlan();
     } else if (plan == SRS_CONF_DEFAULT_DVR_PLAN_APPEND) {
         return new SrsDvrAppendPlan();
+    } else if (plan == SRS_CONF_DEFAULT_DVR_PLAN_API) {
+        return new SrsDvrApiPlan();
     } else {
         srs_error("invalid dvr plan=%s, vhost=%s", plan.c_str(), vhost.c_str());
         srs_assert(false);
@@ -721,6 +724,56 @@ void SrsDvrSessionPlan::on_unpublish()
     dvr_enabled = false;
 }
 
+SrsDvrApiPlan::SrsDvrApiPlan()
+{
+}
+
+SrsDvrApiPlan::~SrsDvrApiPlan()
+{
+}
+
+int SrsDvrApiPlan::on_publish()
+{
+    int ret = ERROR_SUCCESS;
+    
+    // support multiple publish.
+    if (dvr_enabled) {
+        return ret;
+    }
+
+    if (!_srs_config->get_dvr_enabled(req->vhost)) {
+        return ret;
+    }
+
+    if ((ret = segment->close()) != ERROR_SUCCESS) {
+        return ret;
+    }
+
+    if ((ret = segment->open()) != ERROR_SUCCESS) {
+        return ret;
+    }
+
+    dvr_enabled = true;
+
+    return ret;
+}
+
+void SrsDvrApiPlan::on_unpublish()
+{
+    // support multiple publish.
+    if (!dvr_enabled) {
+        return;
+    }
+    
+    // ignore error.
+    int ret = segment->close();
+    if (ret != ERROR_SUCCESS) {
+        srs_warn("ignore flv close error. ret=%d", ret);
+    }
+    
+    dvr_enabled = false;
+}
+
 SrsDvrAppendPlan::SrsDvrAppendPlan()
 {
     last_update_time = 0;
@@ -977,6 +1030,29 @@ int SrsDvrSegmentPlan::update_duration(SrsSharedPtrMessage* msg)
     return ret;
 }
 
+SrsApiDvrPool* SrsApiDvrPool::_instance = new SrsApiDvrPool();
+
+SrsApiDvrPool* SrsApiDvrPool::instance()
+{
+    return SrsApiDvrPool::_instance;
+}
+
+SrsApiDvrPool::SrsApiDvrPool()
+{
+}
+
+SrsApiDvrPool::~SrsApiDvrPool()
+{
+}
+
+int SrsApiDvrPool::dumps(stringstream& ss)
+{
+    int ret = ERROR_SUCCESS;
+    ss << __SRS_JARRAY_START
+        << __SRS_JARRAY_END;
+    return ret;
+}
+
 SrsDvr::SrsDvr(SrsSource* s)
 {
     source = s;
diff --git a/trunk/src/app/srs_app_dvr.hpp b/trunk/src/app/srs_app_dvr.hpp
index e66ea9eb3..f3e6ce1bb 100644
--- a/trunk/src/app/srs_app_dvr.hpp
+++ b/trunk/src/app/srs_app_dvr.hpp
@@ -30,6 +30,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <srs_core.hpp>
 
 #include <string>
+#include <sstream>
 
 #ifdef SRS_AUTO_DVR
 
@@ -223,6 +224,19 @@ public:
     virtual void on_unpublish();
 };
 
+/**
+* api plan: reap flv by api.
+*/
+class SrsDvrApiPlan : public SrsDvrPlan
+{
+public:
+    SrsDvrApiPlan();
+    virtual ~SrsDvrApiPlan();
+public:
+    virtual int on_publish();
+    virtual void on_unpublish();
+};
+
 /**
 * always append to flv file, never reap it.
 */
@@ -282,6 +296,22 @@ private:
     virtual int update_duration(SrsSharedPtrMessage* msg);
 };
 
+/**
+* the api dvr pool.
+*/
+class SrsApiDvrPool
+{
+private:
+    static SrsApiDvrPool* _instance;
+private:
+    SrsApiDvrPool();
+public:
+    static SrsApiDvrPool* instance();
+    virtual ~SrsApiDvrPool();
+public:
+    virtual int dumps(std::stringstream& ss);
+};
+
 /**
 * dvr(digital video recorder) to record RTMP stream to flv file.
 * TODO: FIXME: add utest for it.
diff --git a/trunk/src/app/srs_app_http.cpp b/trunk/src/app/srs_app_http.cpp
index 9333f7af5..5ad63ca99 100644
--- a/trunk/src/app/srs_app_http.cpp
+++ b/trunk/src/app/srs_app_http.cpp
@@ -139,6 +139,9 @@ bool srs_go_http_body_allowd(int status)
 // returns "application/octet-stream".
 string srs_go_http_detect(char* data, int size)
 {
+    // detect only when data specified.
+    if (data) {
+    }
     return "application/octet-stream"; // fallback
 }
 
@@ -715,8 +718,8 @@ int SrsGoHttpResponseWriter::final_request()
         return skt->write((void*)ch.data(), (int)ch.length(), NULL);
     }
     
-    // ignore when send with content length
-    return ERROR_SUCCESS;
+    // flush when send with content length
+    return write(NULL, 0);
 }
 
 SrsGoHttpHeader* SrsGoHttpResponseWriter::header()
@@ -743,6 +746,11 @@ int SrsGoHttpResponseWriter::write(char* data, int size)
         srs_error("http: send header failed. ret=%d", ret);
         return ret;
     }
+
+    // ignore NULL content.
+    if (!data) {
+        return ret;
+    }
     
     // directly send with content length
     if (content_length != -1) {
diff --git a/trunk/src/app/srs_app_http.hpp b/trunk/src/app/srs_app_http.hpp
index abc4f29f3..b0745fd8e 100644
--- a/trunk/src/app/srs_app_http.hpp
+++ b/trunk/src/app/srs_app_http.hpp
@@ -123,6 +123,29 @@ public:
 
 // A ResponseWriter interface is used by an HTTP handler to
 // construct an HTTP response.
+// Usage 1, response with specified length content:
+//      ISrsGoHttpResponseWriter* w; // create or get response.
+//      std::string msg = "Hello, HTTP!";
+//      w->header()->set_content_type("text/plain; charset=utf-8");
+//      w->header()->set_content_length(msg.length());
+//      w->write_header(SRS_CONSTS_HTTP_OK);
+//      w->write((char*)msg.data(), (int)msg.length());
+//      w->final_request(); // optional flush.
+// Usage 2, response with HTTP code only, zero content length.
+//      ISrsGoHttpResponseWriter* w; // create or get response.
+//      w->header()->set_content_length(0);
+//      w->write_header(SRS_CONSTS_HTTP_OK);
+//      w->final_request();
+// Usage 3, response in chunked encoding.
+//      ISrsGoHttpResponseWriter* w; // create or get response.
+//      std::string msg = "Hello, HTTP!";
+//      w->header()->set_content_type("application/octet-stream");
+//      w->write_header(SRS_CONSTS_HTTP_OK);
+//      w->write((char*)msg.data(), (int)msg.length());
+//      w->write((char*)msg.data(), (int)msg.length());
+//      w->write((char*)msg.data(), (int)msg.length());
+//      w->write((char*)msg.data(), (int)msg.length());
+//      w->final_request(); // required to end the chunked and flush.
 class ISrsGoHttpResponseWriter
 {
 public:
@@ -143,6 +166,7 @@ public:
     // before writing the data.  If the Header does not contain a
     // Content-Type line, Write adds a Content-Type set to the result of passing
     // the initial 512 bytes of written data to DetectContentType.
+    // @param data, the data to send. NULL to flush header only.
     virtual int write(char* data, int size) = 0;
     
     // WriteHeader sends an HTTP response header with status code.
diff --git a/trunk/src/app/srs_app_http_api.cpp b/trunk/src/app/srs_app_http_api.cpp
index 8f7dfa6dc..9657a41af 100644
--- a/trunk/src/app/srs_app_http_api.cpp
+++ b/trunk/src/app/srs_app_http_api.cpp
@@ -37,6 +37,8 @@ using namespace std;
 #include <srs_app_utility.hpp>
 #include <srs_app_statistic.hpp>
 #include <srs_rtmp_sdk.hpp>
+#include <srs_app_dvr.hpp>
+#include <srs_app_config.hpp>
 
 SrsGoApiRoot::SrsGoApiRoot()
 {
@@ -472,11 +474,48 @@ int SrsGoApiStreams::serve_http(ISrsGoHttpResponseWriter* w, SrsHttpMessage* r)
     return srs_go_http_response_json(w, ss.str());
 }
 
+SrsGoApiDvrs::SrsGoApiDvrs()
+{
+}
+
+SrsGoApiDvrs::~SrsGoApiDvrs()
+{
+}
+
+int SrsGoApiDvrs::serve_http(ISrsGoHttpResponseWriter* w, SrsHttpMessage* r)
+{
+    std::stringstream ss;
+
+#ifndef SRS_AUTO_DVR
+    ss << __SRS_JOBJECT_START
+        << __SRS_JFIELD_ERROR(ERROR_HTTP_DVR_DISABLED)
+        << __SRS_JOBJECT_END;
+#else
+    SrsApiDvrPool* pool = SrsApiDvrPool::instance();
+    if (r->is_http_get()) {
+        std::stringstream data;
+        int ret = pool->dumps(data);
+
+        ss << __SRS_JOBJECT_START
+            << __SRS_JFIELD_ERROR(ret) << __SRS_JFIELD_CONT
+            << __SRS_JFIELD_ORG("dvrs", data.str())
+            << __SRS_JOBJECT_END;
+    } else {
+        ss << __SRS_JOBJECT_START
+            << __SRS_JFIELD_ERROR(ERROR_HTTP_DVR_REQUEST)
+            << __SRS_JOBJECT_END;
+    }
+#endif
+    
+    return srs_go_http_response_json(w, ss.str());
+}
+
 SrsHttpApi::SrsHttpApi(SrsServer* svr, st_netfd_t fd, SrsGoHttpServeMux* m) 
     : SrsConnection(svr, fd)
 {
     mux = m;
     parser = new SrsHttpParser();
+    crossdomain_required = false;
 }
 
 SrsHttpApi::~SrsHttpApi()
@@ -549,6 +588,29 @@ int SrsHttpApi::process_request(ISrsGoHttpResponseWriter* w, SrsHttpMessage* r)
     srs_trace("HTTP %s %s, content-length=%"PRId64"", 
         r->method_str().c_str(), r->url().c_str(), r->content_length());
     
+    // method is OPTIONS and enable crossdomain, required crossdomain header.
+    if (r->is_http_options() && _srs_config->get_http_api_crossdomain()) {
+        crossdomain_required = true;
+    }
+
+    // whenever crossdomain required, set crossdomain header.
+    if (crossdomain_required) {
+        w->header()->set("Access-Control-Allow-Origin", "*");
+        w->header()->set("Access-Control-Allow-Methods", "GET, POST, HEAD, PUT, DELETE");
+        w->header()->set("Access-Control-Allow-Headers", "Cache-Control,X-Proxy-Authorization,X-Requested-With,Content-Type");
+    }
+
+    // handle the http options.
+    if (r->is_http_options()) {
+        w->header()->set_content_length(0);
+        if (_srs_config->get_http_api_crossdomain()) {
+            w->write_header(SRS_CONSTS_HTTP_OK);
+        } else {
+            w->write_header(SRS_CONSTS_HTTP_MethodNotAllowed);
+        }
+        return w->final_request();
+    }
+    
     // use default server mux to serve http request.
     if ((ret = mux->serve_http(w, r)) != ERROR_SUCCESS) {
         if (!srs_is_client_gracefully_close(ret)) {
diff --git a/trunk/src/app/srs_app_http_api.hpp b/trunk/src/app/srs_app_http_api.hpp
index d21f3683d..067047cda 100644
--- a/trunk/src/app/srs_app_http_api.hpp
+++ b/trunk/src/app/srs_app_http_api.hpp
@@ -159,11 +159,21 @@ public:
     virtual int serve_http(ISrsGoHttpResponseWriter* w, SrsHttpMessage* r);
 };
 
+class SrsGoApiDvrs : public ISrsGoHttpHandler
+{
+public:
+    SrsGoApiDvrs();
+    virtual ~SrsGoApiDvrs();
+public:
+    virtual int serve_http(ISrsGoHttpResponseWriter* w, SrsHttpMessage* r);
+};
+
 class SrsHttpApi : public SrsConnection
 {
 private:
     SrsHttpParser* parser;
     SrsGoHttpServeMux* mux;
+    bool crossdomain_required;
 public:
     SrsHttpApi(SrsServer* svr, st_netfd_t fd, SrsGoHttpServeMux* m);
     virtual ~SrsHttpApi();
diff --git a/trunk/src/app/srs_app_server.cpp b/trunk/src/app/srs_app_server.cpp
index 8be3609f1..7d2481ea5 100644
--- a/trunk/src/app/srs_app_server.cpp
+++ b/trunk/src/app/srs_app_server.cpp
@@ -529,6 +529,9 @@ int SrsServer::initialize()
     if ((ret = http_api_mux->handle("/api/v1/streams", new SrsGoApiStreams())) != ERROR_SUCCESS) {
         return ret;
     }
+    if ((ret = http_api_mux->handle("/api/v1/dvrs", new SrsGoApiDvrs())) != ERROR_SUCCESS) {
+        return ret;
+    }
 #endif
 
 #ifdef SRS_AUTO_HTTP_SERVER
diff --git a/trunk/src/kernel/srs_kernel_error.hpp b/trunk/src/kernel/srs_kernel_error.hpp
index 539045231..994fe92d6 100644
--- a/trunk/src/kernel/srs_kernel_error.hpp
+++ b/trunk/src/kernel/srs_kernel_error.hpp
@@ -209,6 +209,8 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #define ERROR_AAC_ADTS_HEADER               3047
 #define ERROR_AAC_DATA_INVALID              3048
 #define ERROR_HLS_TRY_MP3                   3049
+#define ERROR_HTTP_DVR_DISABLED             3050
+#define ERROR_HTTP_DVR_REQUEST              3051
 
 ///////////////////////////////////////////////////////
 // HTTP/StreamCaster protocol error.