Node.js: ServerResponse.flushHeaders() implemented.

This closes #1006 issue on GitHub.

Reviewed-by: Andrew Clayton <a.clayton@nginx.com>

docs/changes.xml

@@ -33,6 +33,13 @@ can be used as a unique request identifier.
 </para>
 </change>
 
+<change type="feature">
+<para>
+ServerRequest.flushHeaders() implemented in Node.js module to make it compatible
+with Next.js.
+</para>
+</change>
+
 </changes>
 
 

src/nodejs/unit-http/http_server.js

@@ -138,6 +138,10 @@ ServerResponse.prototype.removeHeader = function removeHeader(name) {
     }
 };
 
+ServerResponse.prototype.flushHeaders = function flushHeaders() {
+    this._sendHeaders();
+};
+
 ServerResponse.prototype._removeHeader = function _removeHeader(lc_name) {
     let entry = this.headers[lc_name];
     let name_len = Buffer.byteLength(entry[0] + "", 'latin1');

test/node/flush_headers/app.js

@@ -0,0 +1,7 @@
+
+require('http').createServer(function (req, res) {
+    res.setHeader('X-Header', 'blah');
+    res.flushHeaders();
+    res.flushHeaders(); // Should be idempotent.
+    res.end();
+}).listen(8080);

test/test_node_application.py

@@ -303,6 +303,10 @@ def test_node_application_get_header_names():
         'x-header',
     ], 'get header names'
 
+def test_node_application_flush_headers():
+    client.load('flush_headers')
+
+    assert client.get()['headers']['X-Header'] == 'blah'
 
 def test_node_application_has_header():
     client.load('has_header')