Surface call deadline to Objective C API

src/objective-c/GRPCClient/GRPCCall.h

@@ -169,6 +169,11 @@ extern id const kGRPCTrailersKey;
  */
 @property (atomic, copy, readwrite) NSString *serverName;
 
+/**
+ * The deadline for the RPC call in milliseconds. If set to 0, the deadline will be infinity.
+ */
+@property UInt64 deadline;
+
 /**
  * The container of the request headers of an RPC conforms to this protocol, which is a subset of
  * NSMutableDictionary's interface. It will become a NSMutableDictionary later on.

src/objective-c/GRPCClient/GRPCCall.m

@@ -423,7 +423,8 @@ static NSString * const kBearerPrefix = @"Bearer ";
 
   _wrappedCall = [[GRPCWrappedCall alloc] initWithHost:_host
                                             serverName:_serverName
-                                                  path:_path];
+                                                  path:_path
+                                              deadline:_deadline];
   NSAssert(_wrappedCall, @"Error allocating RPC objects. Low memory?");
 
   [self sendHeaders:_requestHeaders];

src/objective-c/GRPCClient/private/GRPCChannel.h

@@ -63,5 +63,6 @@ struct grpc_channel_credentials;
 
 - (nullable grpc_call *)unmanagedCallWithPath:(nonnull NSString *)path
                                    serverName:(nonnull NSString *)serverName
+                                     deadline:(UInt64)deadline
                               completionQueue:(nonnull GRPCCompletionQueue *)queue;
 @end

src/objective-c/GRPCClient/private/GRPCChannel.m

@@ -182,18 +182,24 @@ static grpc_channel_args *BuildChannelArgs(NSDictionary *dictionary) {
 
 - (grpc_call *)unmanagedCallWithPath:(NSString *)path
                           serverName:(NSString *)serverName
+                            deadline:(UInt64)deadline
                      completionQueue:(GRPCCompletionQueue *)queue {
   grpc_slice host_slice;
   if (serverName) {
     host_slice = grpc_slice_from_copied_string(serverName.UTF8String);
   }
   grpc_slice path_slice = grpc_slice_from_copied_string(path.UTF8String);
+  gpr_timespec deadline_ms = deadline == 0 ?
+                                 gpr_inf_future(GPR_CLOCK_REALTIME) :
+                                 gpr_time_add(
+                                     gpr_now(GPR_CLOCK_MONOTONIC),
+                                     gpr_time_from_millis(deadline, GPR_TIMESPAN));
   grpc_call *call = grpc_channel_create_call(_unmanagedChannel,
                                              NULL, GRPC_PROPAGATE_DEFAULTS,
                                              queue.unmanagedQueue,
                                              path_slice,
                                              serverName ? &host_slice : NULL,
-                                             gpr_inf_future(GPR_CLOCK_REALTIME), NULL);
+                                             deadline_ms, NULL);
   if (serverName) {
     grpc_slice_unref(host_slice);
   }

src/objective-c/GRPCClient/private/GRPCHost.h

@@ -55,6 +55,7 @@ struct grpc_channel_credentials;
 /** Create a grpc_call object to the provided path on this host. */
 - (nullable struct grpc_call *)unmanagedCallWithPath:(NSString *)path
                                           serverName:(NSString *)serverName
+                                            deadline:(UInt64)deadline
                                      completionQueue:(GRPCCompletionQueue *)queue;
 
 // TODO: There's a race when a new RPC is coming through just as an existing one is getting

src/objective-c/GRPCClient/private/GRPCHost.m

@@ -121,6 +121,7 @@ static GRPCConnectivityMonitor *connectivityMonitor = nil;
 
 - (nullable grpc_call *)unmanagedCallWithPath:(NSString *)path
                                    serverName:(NSString *)serverName
+                                     deadline:(UInt64)deadline
                               completionQueue:(GRPCCompletionQueue *)queue {
   GRPCChannel *channel;
   // This is racing -[GRPCHost disconnect].
@@ -130,7 +131,10 @@ static GRPCConnectivityMonitor *connectivityMonitor = nil;
     }
     channel = _channel;
   }
-  return [channel unmanagedCallWithPath:path serverName:serverName completionQueue:queue];
+  return [channel unmanagedCallWithPath:path
+                             serverName:serverName
+                               deadline:deadline
+                        completionQueue:queue];
 }
 
 - (BOOL)setTLSPEMRootCerts:(nullable NSString *)pemRootCerts

src/objective-c/GRPCClient/private/GRPCWrappedCall.h

@@ -76,7 +76,8 @@
 
 - (instancetype)initWithHost:(NSString *)host
                   serverName:(NSString *)serverName
-                        path:(NSString *)path NS_DESIGNATED_INITIALIZER;
+                        path:(NSString *)path
+                    deadline:(UInt64)deadline NS_DESIGNATED_INITIALIZER;
 
 - (void)startBatchWithOperations:(NSArray *)ops errorHandler:(void(^)())errorHandler;
 

src/objective-c/GRPCClient/private/GRPCWrappedCall.m

@@ -238,12 +238,13 @@
 }
 
 - (instancetype)init {
-  return [self initWithHost:nil serverName:nil path:nil];
+  return [self initWithHost:nil serverName:nil path:nil deadline:0];
 }
 
 - (instancetype)initWithHost:(NSString *)host
                   serverName:(NSString *)serverName
-                        path:(NSString *)path {
+                        path:(NSString *)path
+                    deadline:(UInt64)deadline {
   if (!path || !host) {
     [NSException raise:NSInvalidArgumentException
                 format:@"path and host cannot be nil."];
@@ -255,7 +256,10 @@
     // queue. Currently we use a singleton queue.
     _queue = [GRPCCompletionQueue completionQueue];
 
-    _call = [[GRPCHost hostWithAddress:host] unmanagedCallWithPath:path serverName:serverName completionQueue:_queue];
+    _call = [[GRPCHost hostWithAddress:host] unmanagedCallWithPath:path
+                                                        serverName:serverName
+                                                          deadline:deadline
+                                                   completionQueue:_queue];
     if (_call == NULL) {
       return nil;
     }

src/objective-c/tests/GRPCClientTests.m

@@ -422,4 +422,25 @@ static GRPCProtoMethod *kUnaryCallMethod;
   [self waitForExpectationsWithTimeout:TEST_TIMEOUT handler:nil];
 }
 
+- (void)testDeadline {
+  __weak XCTestExpectation *completion = [self expectationWithDescription:@"Empty RPC completed."];
+
+  GRPCCall *call = [[GRPCCall alloc] initWithHost:kHostAddress
+                                             path:kEmptyCallMethod.HTTPPath
+                                   requestsWriter:[GRXWriter writerWithValue:[NSData data]]];
+
+  id<GRXWriteable> responsesWriteable = [[GRXWriteable alloc] initWithValueHandler:^(NSData *value) {
+    XCTAssert(0, @"Failure: response received; Expect: no response received.");
+  } completionHandler:^(NSError *errorOrNil) {
+    XCTAssertNotNil(errorOrNil, @"Failure: no error received; Expect: receive deadline exceeded.");
+    XCTAssertEqual(errorOrNil.code, GRPCErrorCodeDeadlineExceeded);
+    [completion fulfill];
+  }];
+
+  call.deadline = 1;
+  [call startWithWriteable:responsesWriteable];
+
+  [self waitForExpectationsWithTimeout:TEST_TIMEOUT handler:nil];
+}
+
 @end