From 4ef8abddf240c0d16ecd12be247ceb5d933f3e4b Mon Sep 17 00:00:00 2001
From: Michael Lumish <mlumish@google.com>
Date: Fri, 8 May 2020 10:47:35 -0700
Subject: [PATCH 1/2] grpc-js: Don't split header values by commas

---
 packages/grpc-js/src/metadata.ts | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/packages/grpc-js/src/metadata.ts b/packages/grpc-js/src/metadata.ts
index 2da9d531..4947bf0a 100644
--- a/packages/grpc-js/src/metadata.ts
+++ b/packages/grpc-js/src/metadata.ts
@@ -278,11 +278,7 @@ export class Metadata {
               result.add(key, value);
             });
           } else if (values !== undefined) {
-            if (isCustomMetadata(key)) {
-              values.split(',').forEach((v) => result.add(key, v.trim()));
-            } else {
-              result.add(key, values);
-            }
+            result.add(key, values);
           }
         }
       } catch (error) {

From c6deb792697ac9971a25c4f4bafe7931bfec215a Mon Sep 17 00:00:00 2001
From: Michael Lumish <mlumish@google.com>
Date: Thu, 21 May 2020 10:12:08 -0700
Subject: [PATCH 2/2] Test header splitting behavior

---
 packages/grpc-js/test/test-metadata.ts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/packages/grpc-js/test/test-metadata.ts b/packages/grpc-js/test/test-metadata.ts
index a56798ac..44182ef3 100644
--- a/packages/grpc-js/test/test-metadata.ts
+++ b/packages/grpc-js/test/test-metadata.ts
@@ -295,6 +295,7 @@ describe('Metadata', () => {
         key1: 'value1',
         key2: ['value2'],
         key3: ['value3a', 'value3b'],
+        key4: ['part1, part2'],
         'key-bin': [
           'AAECAwQFBgcICQoLDA0ODw==',
           'EBESExQVFhcYGRobHB0eHw==',
@@ -307,6 +308,7 @@ describe('Metadata', () => {
         ['key1', ['value1']],
         ['key2', ['value2']],
         ['key3', ['value3a', 'value3b']],
+        ['key4', ['part1, part2']],
         [
           'key-bin',
           [