From c88af232c847445dfb60c9dda3e46f512084fe3e Mon Sep 17 00:00:00 2001
From: Gerhard Stoebich <deb2001-github@yahoo.de>
Date: Fri, 15 Jun 2018 23:37:46 +0200
Subject: [PATCH] http2: pass incoming set-cookie header as array

Incoming set-cookie headers should be passed to user as array like in
http module.

Besides improving compatibility between http and http2 it avoids the
need to check if the type is an array or not in user code.

PR-URL: https://github.com/nodejs/node/pull/21360
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
---
 doc/api/http2.md                              |  3 +-
 lib/internal/http2/util.js                    |  7 +--
 test/parallel/test-http2-util-headers-list.js | 44 +++++++++++++++++--
 3 files changed, 44 insertions(+), 10 deletions(-)

diff --git a/doc/api/http2.md b/doc/api/http2.md
index b320e1d632354b..3e1850a6790b94 100644
--- a/doc/api/http2.md
+++ b/doc/api/http2.md
@@ -2130,8 +2130,7 @@ For incoming headers:
 `proxy-authorization`, `range`, `referer`,`retry-after`, `tk`,
 `upgrade-insecure-requests`, `user-agent` or `x-content-type-options` are
 discarded.
-* `set-cookie` is a string if present once or an array in case duplicates
-are present.
+* `set-cookie` is always an array. Duplicates are added to the array.
 * `cookie`: the values are joined together with '; '.
 * For all other headers, the values are joined together with ', '.
 
diff --git a/lib/internal/http2/util.js b/lib/internal/http2/util.js
index bf5d07219391e2..bc93662a70239d 100644
--- a/lib/internal/http2/util.js
+++ b/lib/internal/http2/util.js
@@ -509,7 +509,7 @@ function toHeaderObject(headers) {
       value |= 0;
     var existing = obj[name];
     if (existing === undefined) {
-      obj[name] = value;
+      obj[name] = name === HTTP2_HEADER_SET_COOKIE ? [value] : value;
     } else if (!kSingleValueHeaders.has(name)) {
       switch (name) {
         case HTTP2_HEADER_COOKIE:
@@ -528,10 +528,7 @@ function toHeaderObject(headers) {
           // fields with the same name.  Since it cannot be combined into a
           // single field-value, recipients ought to handle "Set-Cookie" as a
           // special case while processing header fields."
-          if (Array.isArray(existing))
-            existing.push(value);
-          else
-            obj[name] = [existing, value];
+          existing.push(value);
           break;
         default:
           // https://tools.ietf.org/html/rfc7230#section-3.2.2
diff --git a/test/parallel/test-http2-util-headers-list.js b/test/parallel/test-http2-util-headers-list.js
index 772e9c8679feef..7b838835531977 100644
--- a/test/parallel/test-http2-util-headers-list.js
+++ b/test/parallel/test-http2-util-headers-list.js
@@ -1,14 +1,14 @@
 // Flags: --expose-internals
 'use strict';
 
-// Tests the internal utility function that is used to prepare headers
-// to pass to the internal binding layer.
+// Tests the internal utility functions that are used to prepare headers
+// to pass to the internal binding layer and to build a header object.
 
 const common = require('../common');
 if (!common.hasCrypto)
   common.skip('missing crypto');
 const assert = require('assert');
-const { mapToHeaders } = require('internal/http2/util');
+const { mapToHeaders, toHeaderObject } = require('internal/http2/util');
 
 const {
   HTTP2_HEADER_STATUS,
@@ -305,3 +305,41 @@ common.expectsError({
 
 assert(!(mapToHeaders({ te: 'trailers' }) instanceof Error));
 assert(!(mapToHeaders({ te: ['trailers'] }) instanceof Error));
+
+
+{
+  const rawHeaders = [
+    ':status', '200',
+    'cookie', 'foo',
+    'set-cookie', 'sc1',
+    'age', '10',
+    'x-multi', 'first'
+  ];
+  const headers = toHeaderObject(rawHeaders);
+  assert.strictEqual(headers[':status'], 200);
+  assert.strictEqual(headers.cookie, 'foo');
+  assert.deepStrictEqual(headers['set-cookie'], ['sc1']);
+  assert.strictEqual(headers.age, '10');
+  assert.strictEqual(headers['x-multi'], 'first');
+}
+
+{
+  const rawHeaders = [
+    ':status', '200',
+    ':status', '400',
+    'cookie', 'foo',
+    'cookie', 'bar',
+    'set-cookie', 'sc1',
+    'set-cookie', 'sc2',
+    'age', '10',
+    'age', '20',
+    'x-multi', 'first',
+    'x-multi', 'second'
+  ];
+  const headers = toHeaderObject(rawHeaders);
+  assert.strictEqual(headers[':status'], 200);
+  assert.strictEqual(headers.cookie, 'foo; bar');
+  assert.deepStrictEqual(headers['set-cookie'], ['sc1', 'sc2']);
+  assert.strictEqual(headers.age, '10');
+  assert.strictEqual(headers['x-multi'], 'first, second');
+}