Only custom-metadata headers should be parsed as comma-separated

packages/grpc-js/src/metadata-status-filter.ts

@@ -38,7 +38,7 @@ export class MetadataStatusFilter extends BaseFilter implements Filter {
       metadata.remove('grpc-status');
     }
     if (typeof metadataMap['grpc-message'] === 'string') {
-      details = decodeURIComponent(metadataMap['grpc-message'] as string);
+      details = decodeURI(metadataMap['grpc-message'] as string);
       metadata.remove('grpc-message');
     }
     return { code, details, metadata };

packages/grpc-js/src/metadata.ts

@@ -36,6 +36,10 @@ function isBinaryKey(key: string): boolean {
   return key.endsWith('-bin');
 }
 
+function isCustomMetadata(key: string): boolean {
+  return !key.startsWith('grpc-');
+}
+
 function normalizeKey(key: string): string {
   return key.toLowerCase();
 }
@@ -260,9 +264,13 @@ export class Metadata {
               result.add(key, Buffer.from(value, 'base64'));
             });
           } else if (values !== undefined) {
-            values.split(',').forEach(v => {
+            if (isCustomMetadata(key)) {
-              result.add(key, Buffer.from(v.trim(), 'base64'));
+              values.split(',').forEach(v => {
-            });
+                result.add(key, Buffer.from(v.trim(), 'base64'));
+              });
+            } else {
+              result.add(key, Buffer.from(values, 'base64'));
+            }
           }
         } else {
           if (Array.isArray(values)) {
@@ -270,7 +278,11 @@ export class Metadata {
               result.add(key, value);
             });
           } else if (values !== undefined) {
-            values.split(',').forEach(v => result.add(key, v.trim()));
+            if (isCustomMetadata(key)) {
+              values.split(',').forEach(v => result.add(key, v.trim()));
+            } else {
+              result.add(key, values);
+            }
           }
         }
       } catch (error) {

packages/grpc-js/src/server-call.ts

@@ -484,9 +484,7 @@ export class Http2ServerCallStream<
         const trailersToSend = Object.assign(
           {
             [GRPC_STATUS_HEADER]: statusObj.code,
-            [GRPC_MESSAGE_HEADER]: encodeURIComponent(
+            [GRPC_MESSAGE_HEADER]: encodeURI(statusObj.details as string),
-              statusObj.details as string
-            ),
           },
           statusObj.metadata.toHttp2Headers()
         );

test/api/error_test.js

@@ -553,6 +553,14 @@ describe(`${anyGrpc.clientName} client -> ${anyGrpc.serverName} server`, functio
             done();
           });
         });
+        it('for an error message with a comma', function(done) {
+          client.unary({error: true, message: 'a message,  with a comma'}, function(err, data) {
+            assert(err);
+            assert.strictEqual(err.code, clientGrpc.status.UNKNOWN);
+            assert.strictEqual(err.details, 'a message,  with a comma');
+            done();
+          });
+        });
       });
   });
 });