[v19.x backport] http: res set headers

doc/api/http.md

@@ -2958,6 +2958,48 @@ Sets a single header value. If the header already exists in the to-be-sent
 headers, its value will be replaced. Use an array of strings to send multiple
 headers with the same name.
 
+### `outgoingMessage.setHeaders(headers)`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+* `headers` {Headers|Map}
+* Returns: {http.ServerResponse}
+
+Returns the response object.
+
+Sets multiple header values for implicit headers.
+`headers` must be an instance of [`Headers`][] or `Map`,
+if a header already exists in the to-be-sent headers,
+its value will be replaced.
+
+```js
+const headers = new Headers({ foo: 'bar' });
+response.setHeaders(headers);
+```
+
+or
+
+```js
+const headers = new Map([['foo', 'bar']]);
+res.setHeaders(headers);
+```
+
+When headers have been set with [`outgoingMessage.setHeaders()`][],
+they will be merged with any headers passed to [`response.writeHead()`][],
+with the headers passed to [`response.writeHead()`][] given precedence.
+
+```js
+// Returns content-type = text/plain
+const server = http.createServer((req, res) => {
+  const headers = new Headers({ 'Content-Type': 'text/html' });
+  res.setHeaders(headers);
+  res.writeHead(200, { 'Content-Type': 'text/plain' });
+  res.end('ok');
+});
+```
+
 ### `outgoingMessage.setTimeout(msesc[, callback])`
 
 <!-- YAML
@@ -3737,6 +3779,7 @@ Set the maximum number of idle HTTP parsers. **Default:** `1000`.
 [`Buffer.byteLength()`]: buffer.md#static-method-bufferbytelengthstring-encoding
 [`Duplex`]: stream.md#class-streamduplex
 [`HPE_HEADER_OVERFLOW`]: errors.md#hpe_header_overflow
+[`Headers`]: globals.md#class-headers
 [`TypeError`]: errors.md#class-typeerror
 [`URL`]: url.md#the-whatwg-url-api
 [`agent.createConnection()`]: #agentcreateconnectionoptions-callback
@@ -3762,6 +3805,7 @@ Set the maximum number of idle HTTP parsers. **Default:** `1000`.
 [`net.createConnection()`]: net.md#netcreateconnectionoptions-connectlistener
 [`new URL()`]: url.md#new-urlinput-base
 [`outgoingMessage.setHeader(name, value)`]: #outgoingmessagesetheadername-value
+[`outgoingMessage.setHeaders()`]: #outgoingmessagesetheadersheaders
 [`outgoingMessage.socket`]: #outgoingmessagesocket
 [`removeHeader(name)`]: #requestremoveheadername
 [`request.destroy()`]: #requestdestroyerror

lib/_http_outgoing.js

@@ -673,6 +673,28 @@ OutgoingMessage.prototype.setHeader = function setHeader(name, value) {
   return this;
 };
 
+OutgoingMessage.prototype.setHeaders = function setHeaders(headers) {
+  if (this._header) {
+    throw new ERR_HTTP_HEADERS_SENT('set');
+  }
+
+
+  if (
+    !headers ||
+    ArrayIsArray(headers) ||
+    typeof headers.keys !== 'function' ||
+    typeof headers.get !== 'function'
+  ) {
+    throw new ERR_INVALID_ARG_TYPE('headers', ['Headers', 'Map'], headers);
+  }
+
+  for (const key of headers.keys()) {
+    this.setHeader(key, headers.get(key));
+  }
+
+  return this;
+};
+
 OutgoingMessage.prototype.appendHeader = function appendHeader(name, value) {
   if (this._header) {
     throw new ERR_HTTP_HEADERS_SENT('append');

test/parallel/test-http-response-setheaders.js

@@ -0,0 +1,131 @@
+'use strict';
+const common = require('../common');
+const http = require('http');
+const assert = require('assert');
+
+{
+  const server = http.createServer(common.mustCall((req, res) => {
+    res.writeHead(200); // Headers already sent
+    const headers = new globalThis.Headers({ foo: '1' });
+    assert.throws(() => {
+      res.setHeaders(headers);
+    }, {
+      code: 'ERR_HTTP_HEADERS_SENT'
+    });
+    res.end();
+  }));
+
+  server.listen(0, common.mustCall(() => {
+    http.get({ port: server.address().port }, (res) => {
+      assert.strictEqual(res.headers.foo, undefined);
+      res.resume().on('end', common.mustCall(() => {
+        server.close();
+      }));
+    });
+  }));
+}
+
+{
+  const server = http.createServer(common.mustCall((req, res) => {
+    assert.throws(() => {
+      res.setHeaders(['foo', '1']);
+    }, {
+      code: 'ERR_INVALID_ARG_TYPE'
+    });
+    assert.throws(() => {
+      res.setHeaders({ foo: '1' });
+    }, {
+      code: 'ERR_INVALID_ARG_TYPE'
+    });
+    assert.throws(() => {
+      res.setHeaders(null);
+    }, {
+      code: 'ERR_INVALID_ARG_TYPE'
+    });
+    assert.throws(() => {
+      res.setHeaders(undefined);
+    }, {
+      code: 'ERR_INVALID_ARG_TYPE'
+    });
+    assert.throws(() => {
+      res.setHeaders('test');
+    }, {
+      code: 'ERR_INVALID_ARG_TYPE'
+    });
+    assert.throws(() => {
+      res.setHeaders(1);
+    }, {
+      code: 'ERR_INVALID_ARG_TYPE'
+    });
+    res.end();
+  }));
+
+  server.listen(0, common.mustCall(() => {
+    http.get({ port: server.address().port }, (res) => {
+      assert.strictEqual(res.headers.foo, undefined);
+      res.resume().on('end', common.mustCall(() => {
+        server.close();
+      }));
+    });
+  }));
+}
+
+{
+  const server = http.createServer(common.mustCall((req, res) => {
+    const headers = new globalThis.Headers({ foo: '1', bar: '2' });
+    res.setHeaders(headers);
+    res.writeHead(200);
+    res.end();
+  }));
+
+  server.listen(0, common.mustCall(() => {
+    http.get({ port: server.address().port }, (res) => {
+      assert.strictEqual(res.statusCode, 200);
+      assert.strictEqual(res.headers.foo, '1');
+      assert.strictEqual(res.headers.bar, '2');
+      res.resume().on('end', common.mustCall(() => {
+        server.close();
+      }));
+    });
+  }));
+}
+
+{
+  const server = http.createServer(common.mustCall((req, res) => {
+    const headers = new globalThis.Headers({ foo: '1', bar: '2' });
+    res.setHeaders(headers);
+    res.writeHead(200, ['foo', '3']);
+    res.end();
+  }));
+
+  server.listen(0, common.mustCall(() => {
+    http.get({ port: server.address().port }, (res) => {
+      assert.strictEqual(res.statusCode, 200);
+      assert.strictEqual(res.headers.foo, '3'); // Override by writeHead
+      assert.strictEqual(res.headers.bar, '2');
+      res.resume().on('end', common.mustCall(() => {
+        server.close();
+      }));
+    });
+  }));
+}
+
+{
+  const server = http.createServer(common.mustCall((req, res) => {
+    const headers = new Map([['foo', '1'], ['bar', '2']]);
+    res.setHeaders(headers);
+    res.writeHead(200);
+    res.end();
+  }));
+
+  server.listen(0, common.mustCall(() => {
+    http.get({ port: server.address().port }, (res) => {
+      assert.strictEqual(res.statusCode, 200);
+      assert.strictEqual(res.headers.foo, '1');
+      assert.strictEqual(res.headers.bar, '2');
+      res.resume().on('end', common.mustCall(() => {
+        server.close();
+      }));
+    });
+  }));
+}