send a reason on close frame in websocket connection indicating the error

include/ngx_http_push_stream_module.h

@@ -324,6 +324,8 @@ static const u_char NGX_HTTP_PUSH_STREAM_WEBSOCKET_PING_LAST_FRAME_BYTE[]  = {NG
 static const u_char NGX_HTTP_PUSH_STREAM_WEBSOCKET_PAYLOAD_LEN_16_BYTE   = 126;
 static const u_char NGX_HTTP_PUSH_STREAM_WEBSOCKET_PAYLOAD_LEN_64_BYTE   = 127;
 
+static const ngx_str_t NGX_HTTP_PUSH_STREAM_WEBSOCKET_CLOSE_REASON = ngx_string("\x03\xF0{\"http_status\": %d, \"explain\":\"%V\"}");
+
 
 // other stuff
 static const ngx_str_t  NGX_HTTP_PUSH_STREAM_ALLOW_GET_POST_PUT_DELETE_METHODS = ngx_string("GET, POST, PUT, DELETE");

include/ngx_http_push_stream_module_utils.h

@@ -233,7 +233,7 @@ static ngx_table_elt_t *    ngx_http_push_stream_add_response_header(ngx_http_re
 static ngx_str_t *          ngx_http_push_stream_get_header(ngx_http_request_t *r, const ngx_str_t *header_name);
 static ngx_int_t            ngx_http_push_stream_send_only_header_response(ngx_http_request_t *r, ngx_int_t status, const ngx_str_t *explain_error_message);
 static u_char *             ngx_http_push_stream_str_replace(u_char *org, u_char *find, u_char *replace, ngx_uint_t offset, ngx_pool_t *temp_pool);
-static ngx_str_t *          ngx_http_push_stream_get_formatted_websocket_frame(const u_char *text, off_t len, ngx_pool_t *temp_pool);
+static ngx_str_t *          ngx_http_push_stream_get_formatted_websocket_frame(const u_char *opcode, off_t opcode_len, const u_char *text, off_t text_len, ngx_pool_t *temp_pool);
 static ngx_str_t *          ngx_http_push_stream_get_formatted_message(ngx_http_request_t *r, ngx_http_push_stream_channel_t *channel, ngx_http_push_stream_msg_t *msg, ngx_pool_t *temp_pool);
 static ngx_str_t *          ngx_http_push_stream_format_message(ngx_http_push_stream_channel_t *channel, ngx_http_push_stream_msg_t *message, ngx_str_t *text, ngx_str_t *message_template, ngx_pool_t *temp_pool);
 static ngx_str_t *          ngx_http_push_stream_apply_template_to_each_line(ngx_str_t *text, const ngx_str_t *message_template, ngx_pool_t *temp_pool);
@@ -243,6 +243,7 @@ static ngx_int_t            ngx_http_push_stream_send_response_message(ngx_http_
 static ngx_int_t            ngx_http_push_stream_send_response_text(ngx_http_request_t *r, const u_char *text, uint len, ngx_flag_t last_buffer);
 static void                 ngx_http_push_stream_send_response_finalize(ngx_http_request_t *r);
 static void                 ngx_http_push_stream_send_response_finalize_for_longpolling_by_timeout(ngx_http_request_t *r);
+static ngx_int_t            ngx_http_push_stream_send_websocket_close_frame(ngx_http_request_t *r, ngx_uint_t http_status, const ngx_str_t *reason);
 static ngx_int_t            ngx_http_push_stream_memory_cleanup();
 static ngx_int_t            ngx_http_push_stream_buffer_cleanup();
 

misc/spec/subscriber/websocket_spec.rb

@@ -191,6 +191,21 @@ describe "Subscriber WebSocket" do
     end
   end
 
+  it "should receive explain message on close frame" do
+    channel = 'ch_test_receive_explain_message_close_frame'
+    request = "GET /ws/#{channel}.b1 HTTP/1.0\r\nConnection: Upgrade\r\nSec-WebSocket-Key: /mQoZf6pRiv8+6o72GncLQ==\r\nUpgrade: websocket\r\nSec-WebSocket-Version: 8\r\n"
+
+    nginx_run_server(config.merge(:subscriber_connection_ttl => '1s', :authorized_channels_only => 'on')) do |conf|
+      socket = open_socket(nginx_host, nginx_port)
+      socket.print("#{request}\r\n")
+      headers, body = read_response_on_socket(socket)
+      #wait for disconnect
+      sleep(1)
+      body, dummy = read_response_on_socket(socket, "\"}")
+      body.should eql("\x88I\x03\xF0{\"http_status\": 403, \"explain\":\"Subscriber could not create channels.\"}")
+    end
+  end
+
   it "should receive footer template" do
     channel = 'ch_test_receive_footer_template'
     request = "GET /ws/#{channel}.b1 HTTP/1.0\r\nConnection: Upgrade\r\nSec-WebSocket-Key: /mQoZf6pRiv8+6o72GncLQ==\r\nUpgrade: websocket\r\nSec-WebSocket-Version: 8\r\n"

src/ngx_http_push_stream_module_setup.c

@@ -640,7 +640,7 @@ ngx_http_push_stream_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
     } else if (conf->location_type == NGX_HTTP_PUSH_STREAM_SUBSCRIBER_MODE_WEBSOCKET) {
         // formatting header and footer template for chunk transfer
         if (conf->header_template.len > 0) {
-            ngx_str_t *aux = ngx_http_push_stream_get_formatted_websocket_frame(conf->header_template.data, conf->header_template.len, cf->pool);
+            ngx_str_t *aux = ngx_http_push_stream_get_formatted_websocket_frame(&NGX_HTTP_PUSH_STREAM_WEBSOCKET_TEXT_LAST_FRAME_BYTE, sizeof(NGX_HTTP_PUSH_STREAM_WEBSOCKET_TEXT_LAST_FRAME_BYTE), conf->header_template.data, conf->header_template.len, cf->pool);
             if (aux == NULL) {
                 ngx_conf_log_error(NGX_LOG_ERR, cf, 0, "push stream module: unable to allocate memory to format header template");
                 return NGX_CONF_ERROR;
@@ -650,7 +650,7 @@ ngx_http_push_stream_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
         }
 
         if (conf->footer_template.len > 0) {
-            ngx_str_t *aux = ngx_http_push_stream_get_formatted_websocket_frame(conf->footer_template.data, conf->footer_template.len, cf->pool);
+            ngx_str_t *aux = ngx_http_push_stream_get_formatted_websocket_frame(&NGX_HTTP_PUSH_STREAM_WEBSOCKET_TEXT_LAST_FRAME_BYTE, sizeof(NGX_HTTP_PUSH_STREAM_WEBSOCKET_TEXT_LAST_FRAME_BYTE), conf->footer_template.data, conf->footer_template.len, cf->pool);
             if (aux == NULL) {
                 ngx_conf_log_error(NGX_LOG_ERR, cf, 0, "push stream module: unable to allocate memory to format footer template");
                 return NGX_CONF_ERROR;

src/ngx_http_push_stream_module_subscriber.c

@@ -35,6 +35,7 @@ static ngx_http_push_stream_subscription_t      *ngx_http_push_stream_create_cha
 static ngx_int_t                                 ngx_http_push_stream_assing_subscription_to_channel_locked(ngx_slab_pool_t *shpool, ngx_str_t *channel_id, ngx_http_push_stream_subscription_t *subscription, ngx_http_push_stream_subscription_t *subscriptions_sentinel, ngx_log_t *log);
 static ngx_int_t                                 ngx_http_push_stream_subscriber_polling_handler(ngx_http_request_t *r, ngx_http_push_stream_requested_channel_t *channels_ids, time_t if_modified_since, ngx_int_t tag, ngx_str_t *last_event_id, ngx_flag_t longpolling, ngx_pool_t *temp_pool);
 static ngx_http_push_stream_padding_t           *ngx_http_push_stream_get_padding_by_user_agent(ngx_http_request_t *r);
+void                                             ngx_http_push_stream_websocket_reading(ngx_http_request_t *r);
 
 static ngx_int_t
 ngx_http_push_stream_subscriber_handler(ngx_http_request_t *r)
@@ -416,7 +417,7 @@ ngx_http_push_stream_subscriber_prepare_request_to_keep_connected(ngx_http_reque
     r->main->count++;
 
     // responding subscriber
-    r->read_event_handler = ngx_http_test_reading;
+    r->read_event_handler = (cf->location_type == NGX_HTTP_PUSH_STREAM_SUBSCRIBER_MODE_WEBSOCKET) ? ngx_http_push_stream_websocket_reading : ngx_http_test_reading;
     r->write_event_handler = ngx_http_request_empty_handler;
 
     if (cf->location_type == NGX_HTTP_PUSH_STREAM_SUBSCRIBER_MODE_EVENTSOURCE) {

src/ngx_http_push_stream_module_utils.c

@@ -287,7 +287,7 @@ ngx_http_push_stream_convert_char_to_msg_on_shared_locked(u_char *data, size_t l
 
         ngx_str_t *text = aux;
         if (cur->websocket) {
-            text = ngx_http_push_stream_get_formatted_websocket_frame(aux->data, aux->len, temp_pool);
+            text = ngx_http_push_stream_get_formatted_websocket_frame(&NGX_HTTP_PUSH_STREAM_WEBSOCKET_TEXT_LAST_FRAME_BYTE, sizeof(NGX_HTTP_PUSH_STREAM_WEBSOCKET_TEXT_LAST_FRAME_BYTE), aux->data, aux->len, temp_pool);
         }
 
         ngx_str_t *formmated = (msg->formatted_messages + i);
@@ -673,6 +673,22 @@ ngx_http_push_stream_send_response_finalize_for_longpolling_by_timeout(ngx_http_
     ngx_http_finalize_request(r, NGX_DONE);
 }
 
+static ngx_int_t
+ngx_http_push_stream_send_websocket_close_frame(ngx_http_request_t *r, ngx_uint_t http_status, const ngx_str_t *reason)
+{
+    ngx_int_t rc;
+    ngx_str_t *text = ngx_http_push_stream_create_str(r->pool, reason->len + NGX_INT_T_LEN + NGX_HTTP_PUSH_STREAM_WEBSOCKET_CLOSE_REASON.len);
+    if (text == NULL) {
+        rc = ngx_http_push_stream_send_response_text(r, NGX_HTTP_PUSH_STREAM_WEBSOCKET_CLOSE_LAST_FRAME_BYTE, sizeof(NGX_HTTP_PUSH_STREAM_WEBSOCKET_CLOSE_LAST_FRAME_BYTE), 1);
+    } else {
+        u_char *last = ngx_sprintf(text->data, (char *) NGX_HTTP_PUSH_STREAM_WEBSOCKET_CLOSE_REASON.data, http_status, reason);
+        text->len = last - text->data;
+        ngx_str_t *frame = ngx_http_push_stream_get_formatted_websocket_frame(NGX_HTTP_PUSH_STREAM_WEBSOCKET_CLOSE_LAST_FRAME_BYTE, 1, text->data, text->len, r->pool);
+        rc = ngx_http_push_stream_send_response_text(r, (const u_char *) frame->data, frame->len, 1);
+    }
+    return (rc == NGX_ERROR) ? NGX_DONE : NGX_OK;
+}
+
 static ngx_flag_t
 ngx_http_push_stream_delete_channel(ngx_str_t *id, u_char *text, size_t len, ngx_pool_t *temp_pool)
 {
@@ -1286,14 +1302,14 @@ ngx_http_push_stream_ntohll(uint64_t value) {
 
 
 static ngx_str_t *
-ngx_http_push_stream_get_formatted_websocket_frame(const u_char *text, off_t len, ngx_pool_t *temp_pool)
+ngx_http_push_stream_get_formatted_websocket_frame(const u_char *opcode, off_t opcode_len, const u_char *text, off_t len, ngx_pool_t *temp_pool)
 {
     ngx_str_t            *frame;
     u_char               *last;
 
     frame = ngx_http_push_stream_create_str(temp_pool, NGX_HTTP_PUSH_STREAM_WEBSOCKET_FRAME_HEADER_MAX_LENGTH + len);
     if (frame != NULL) {
-        last = ngx_copy(frame->data, &NGX_HTTP_PUSH_STREAM_WEBSOCKET_TEXT_LAST_FRAME_BYTE, sizeof(NGX_HTTP_PUSH_STREAM_WEBSOCKET_TEXT_LAST_FRAME_BYTE));
+        last = ngx_copy(frame->data, opcode, opcode_len);
 
         if (len <= 125) {
             last = ngx_copy(last, &len, 1);

src/ngx_http_push_stream_module_websocket.c

@@ -26,7 +26,6 @@
 #include <ngx_http_push_stream_module_websocket.h>
 
 static ngx_str_t *ngx_http_push_stream_generate_websocket_accept_value(ngx_http_request_t *r, ngx_str_t *sec_key, ngx_pool_t *temp_pool);
-void              ngx_http_push_stream_websocket_reading(ngx_http_request_t *r);
 
 static ngx_int_t
 ngx_http_push_stream_websocket_handler(ngx_http_request_t *r)
@@ -79,6 +78,18 @@ ngx_http_push_stream_websocket_handler(ngx_http_request_t *r)
         return NGX_HTTP_INTERNAL_SERVER_ERROR;
     }
 
+    if ((sec_accept_header = ngx_http_push_stream_generate_websocket_accept_value(r, sec_key_header, ctx->temp_pool)) == NULL) {
+        ngx_log_error(NGX_LOG_WARN, r->connection->log, 0, "push stream module: could not generate security accept header value");
+        return NGX_HTTP_INTERNAL_SERVER_ERROR;
+    }
+
+    ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_UPGRADE, &NGX_HTTP_PUSH_STREAM_WEBSOCKET_UPGRADE);
+    ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_CONNECTION, &NGX_HTTP_PUSH_STREAM_WEBSOCKET_CONNECTION);
+    ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_SEC_WEBSOCKET_ACCEPT, sec_accept_header);
+    r->headers_out.status_line = NGX_HTTP_PUSH_STREAM_101_STATUS_LINE;
+
+    ngx_http_push_stream_send_only_added_headers(r);
+
     //get channels ids and backtracks from path
     channels_ids = ngx_http_push_stream_parse_channels_ids_from_path(r, ctx->temp_pool);
     if ((channels_ids == NULL) || ngx_queue_empty(&channels_ids->queue)) {
@@ -88,7 +99,7 @@ ngx_http_push_stream_websocket_handler(ngx_http_request_t *r)
 
     //validate channels: name, length and quantity. check if channel exists when authorized_channels_only is on. check if channel is full of subscribers
     if (ngx_http_push_stream_validate_channels(r, channels_ids, &status_code, &explain_error_message) == NGX_ERROR) {
-        return ngx_http_push_stream_send_only_header_response(r, status_code, explain_error_message);
+        return ngx_http_push_stream_send_websocket_close_frame(r, status_code, explain_error_message);
     }
 
     // get control values
@@ -96,26 +107,13 @@ ngx_http_push_stream_websocket_handler(ngx_http_request_t *r)
 
     // stream access
     if ((worker_subscriber = ngx_http_push_stream_subscriber_prepare_request_to_keep_connected(r)) == NULL) {
-        return NGX_HTTP_INTERNAL_SERVER_ERROR;
+        return ngx_http_push_stream_send_websocket_close_frame(r, NGX_HTTP_INTERNAL_SERVER_ERROR, &NGX_HTTP_PUSH_STREAM_EMPTY);
     }
 
-    if ((sec_accept_header = ngx_http_push_stream_generate_websocket_accept_value(r, sec_key_header, ctx->temp_pool)) == NULL) {
-        ngx_log_error(NGX_LOG_WARN, r->connection->log, 0, "push stream module: could not generate security accept heade value");
-        return NGX_HTTP_INTERNAL_SERVER_ERROR;
-    }
-
-    ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_UPGRADE, &NGX_HTTP_PUSH_STREAM_WEBSOCKET_UPGRADE);
-    ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_CONNECTION, &NGX_HTTP_PUSH_STREAM_WEBSOCKET_CONNECTION);
-    ngx_http_push_stream_add_response_header(r, &NGX_HTTP_PUSH_STREAM_HEADER_SEC_WEBSOCKET_ACCEPT, sec_accept_header);
-    r->headers_out.status_line = NGX_HTTP_PUSH_STREAM_101_STATUS_LINE;
-    r->read_event_handler = ngx_http_push_stream_websocket_reading;
-
-    ngx_http_push_stream_send_only_added_headers(r);
-
     // sending response content header
     if (ngx_http_push_stream_send_response_content_header(r, cf) == NGX_ERROR) {
         ngx_log_error(NGX_LOG_ERR, (r)->connection->log, 0, "push stream module: could not send content header to subscriber");
-        return NGX_HTTP_INTERNAL_SERVER_ERROR;
+        return ngx_http_push_stream_send_websocket_close_frame(r, NGX_HTTP_INTERNAL_SERVER_ERROR, &NGX_HTTP_PUSH_STREAM_EMPTY);
     }
 
     ngx_shmtx_lock(&shpool->mutex);
@@ -123,14 +121,14 @@ ngx_http_push_stream_websocket_handler(ngx_http_request_t *r)
     ngx_shmtx_unlock(&shpool->mutex);
 
     if (rc == NGX_ERROR) {
-        return NGX_HTTP_INTERNAL_SERVER_ERROR;
+        return ngx_http_push_stream_send_websocket_close_frame(r, NGX_HTTP_INTERNAL_SERVER_ERROR, &NGX_HTTP_PUSH_STREAM_EMPTY);
     }
 
     // adding subscriber to channel(s) and send backtrack messages
     cur = channels_ids;
     while ((cur = (ngx_http_push_stream_requested_channel_t *) ngx_queue_next(&cur->queue)) != channels_ids) {
         if (ngx_http_push_stream_subscriber_assign_channel(shpool, cf, r, cur, if_modified_since, tag, last_event_id, worker_subscriber, ctx->temp_pool) != NGX_OK) {
-            return NGX_HTTP_INTERNAL_SERVER_ERROR;
+            return ngx_http_push_stream_send_websocket_close_frame(r, NGX_HTTP_INTERNAL_SERVER_ERROR, &NGX_HTTP_PUSH_STREAM_EMPTY);
         }
     }