grpc-js: Add getHost to surface server call classes

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

@@ -37,6 +37,7 @@ export type ServerSurfaceCall = {
   sendMetadata(responseMetadata: Metadata): void;
   getDeadline(): Deadline;
   getPath(): string;
+  getHost(): string;
 } & EventEmitter;
 
 export type ServerUnaryCall<RequestType, ResponseType> = ServerSurfaceCall & {
@@ -109,6 +110,10 @@ export class ServerUnaryCallImpl<RequestType, ResponseType>
   getPath(): string {
     return this.path;
   }
+
+  getHost(): string {
+    return this.call.getHost();
+  }
 }
 
 export class ServerReadableStreamImpl<RequestType, ResponseType>
@@ -145,6 +150,10 @@ export class ServerReadableStreamImpl<RequestType, ResponseType>
   getPath(): string {
     return this.path;
   }
+
+  getHost(): string {
+    return this.call.getHost();
+  }
 }
 
 export class ServerWritableStreamImpl<RequestType, ResponseType>
@@ -190,6 +199,10 @@ export class ServerWritableStreamImpl<RequestType, ResponseType>
     return this.path;
   }
 
+  getHost(): string {
+    return this.call.getHost();
+  }
+
   _write(
     chunk: ResponseType,
     encoding: string,
@@ -259,6 +272,10 @@ export class ServerDuplexStreamImpl<RequestType, ResponseType>
     return this.path;
   }
 
+  getHost(): string {
+    return this.call.getHost();
+  }
+
   _read(size: number) {
     this.call.startRead();
   }