Consume HTTP trailing headers

doc/api.markdown

@@ -1791,6 +1791,10 @@ you can use the `require('querystring').parse` function, or pass
 
 Read only.
 
+### request.trailers
+
+Read only; HTTP trailers (if present). Only populated after the 'end' event.
+
 ### request.httpVersion
 
 The HTTP protocol version as a string. Read only. Examples:
@@ -2093,6 +2097,10 @@ Also `response.httpVersionMajor` is the first integer and
 
 The response headers object.
 
+### response.trailers
+
+The response trailers object. Only populated after the 'end' event.
+
 ### response.setEncoding(encoding=null)
 
 Set the encoding for the response body. Either `'utf8'`, `'ascii'`, or `'base64'`.

lib/http.js

@@ -60,6 +60,8 @@ var parsers = new FreeList('parsers', 1000, function () {
   parser.onHeadersComplete = function (info) {
     if (parser.field && (parser.value != undefined)) {
       parser.incoming._addHeaderLine(parser.field, parser.value);
+      parser.field = null;
+      parser.value = null;
     }
 
     parser.incoming.httpVersionMajor = info.versionMajor;
@@ -101,6 +103,10 @@ var parsers = new FreeList('parsers', 1000, function () {
   };
 
   parser.onMessageComplete = function () {
+    this.incoming.complete = true;
+    if (parser.field && (parser.value != undefined)) {
+      parser.incoming._addHeaderLine(parser.field, parser.value);
+    }
     if (!parser.incoming.upgrade) {
       // For upgraded connections, also emit this after parser.execute
       parser.incoming.emit("end");
@@ -183,7 +189,9 @@ function IncomingMessage (socket) {
   this.connection = socket;
 
   this.httpVersion = null;
+  this.complete = false;
   this.headers = {};
+  this.trailers = {};
 
   // request (server) only
   this.url = "";
@@ -223,13 +231,19 @@ IncomingMessage.prototype.resume = function () {
 // and drop the second. Extended header fields (those beginning with 'x-') are
 // always joined.
 IncomingMessage.prototype._addHeaderLine = function (field, value) {
+  var dest;
+  if (this.complete) {
+      dest = this.trailers
+  } else {
+      dest = this.headers
+  }
   switch (field) {
     // Array headers:
     case 'set-cookie':
-      if (field in this.headers) {
-        this.headers[field].push(value);
+      if (field in dest) {
+        dest[field].push(value);
       } else {
-        this.headers[field] = [value];
+        dest[field] = [value];
       }
       break;
 
@@ -240,10 +254,10 @@ IncomingMessage.prototype._addHeaderLine = function (field, value) {
     case 'accept-language':
     case 'connection':
     case 'cookie':
-      if (field in this.headers) {
-        this.headers[field] += ', ' + value;
+      if (field in dest) {
+        dest[field] += ', ' + value;
       } else {
-        this.headers[field] = value;
+        dest[field] = value;
       }
       break;
 
@@ -251,14 +265,14 @@ IncomingMessage.prototype._addHeaderLine = function (field, value) {
     default:
       if (field.slice(0,2) == 'x-') {
         // except for x-
-        if (field in this.headers) {
-          this.headers[field] += ', ' + value;
+        if (field in dest) {
+          dest[field] += ', ' + value;
         } else {
-          this.headers[field] = value;
+          dest[field] = value;
         }
       } else {
         // drop duplicates
-        if (!(field in this.headers)) this.headers[field] = value;
+        if (!(field in dest)) dest[field] = value;
       }
       break;
   }

test/simple/test-http-set-trailers.js

@@ -71,5 +71,24 @@ server.addListener("listening", function() {
         }
     }
   });
+});
 
+// now, see if the client sees the trailers.
+server.addListener('listening', function() {
+  var client = http.createClient(common.PORT);
+  var req = client.request("/hello", {});
+  req.end();
+  outstanding_reqs++;
+  req.addListener('response', function (res) {
+    res.addListener('end', function () {
+//      console.log(res.trailers);
+      assert.ok("x-foo" in res.trailers,
+        "Client doesn't see trailers.");
+      outstanding_reqs--;
+      if (outstanding_reqs == 0) {
+        server.close();
+        process.exit();
+      }
+    });
+  });
 });