1 files changed, 43 insertions, 11 deletions

diff --git a/src/objective-c/GRPCClient/GRPCCall.m b/src/objective-c/GRPCClient/GRPCCall.m
index a4a0ddb324..77eebeff76 100644
--- a/src/objective-c/GRPCClient/GRPCCall.m
+++ b/src/objective-c/GRPCClient/GRPCCall.m
@@ -34,7 +34,7 @@
 #import "GRPCCall.h"
 
 #include <grpc/grpc.h>
-#include <grpc/support/grpc_time.h>
+#include <grpc/support/time.h>
 
 #import "GRPCMethodName.h"
 #import "private/GRPCChannel.h"
@@ -46,9 +46,9 @@
 #import "private/NSDictionary+GRPC.h"
 #import "private/NSError+GRPC.h"
 
+NSString * const kGRPCStatusMetadataKey = @"io.grpc.StatusMetadataKey";
+
 @interface GRPCCall () <GRXWriteable>
-// Makes it readwrite.
-@property(atomic, strong) NSDictionary *responseMetadata;
 @end
 
 // The following methods of a C gRPC call object aren't reentrant, and thus
@@ -82,6 +82,9 @@
   // correct ordering.
   GRPCDelegateWrapper *_responseWriteable;
   id<GRXWriter> _requestWriter;
+
+  NSMutableDictionary *_requestMetadata;
+  NSMutableDictionary *_responseMetadata;
 }
 
 @synthesize state = _state;
@@ -97,7 +100,9 @@
   if (!host || !method) {
     [NSException raise:NSInvalidArgumentException format:@"Neither host nor method can be nil."];
   }
-  // TODO(jcanizales): Throw if the requestWriter was already started.
+  if (requestWriter.state != GRXWriterStateNotStarted) {
+    [NSException raise:NSInvalidArgumentException format:@"The requests writer can't be already started."];
+  }
   if ((self = [super init])) {
     static dispatch_once_t initialization;
     dispatch_once(&initialization, ^{
@@ -116,10 +121,27 @@
     _callQueue = dispatch_queue_create("org.grpc.call", NULL);
 
     _requestWriter = requestWriter;
+
+    _requestMetadata = [NSMutableDictionary dictionary];
+    _responseMetadata = [NSMutableDictionary dictionary];
   }
   return self;
 }
 
+#pragma mark Metadata
+
+- (NSMutableDictionary *)requestMetadata {
+  return _requestMetadata;
+}
+
+- (void)setRequestMetadata:(NSDictionary *)requestMetadata {
+  _requestMetadata = [NSMutableDictionary dictionaryWithDictionary:requestMetadata];
+}
+
+- (NSDictionary *)responseMetadata {
+  return _responseMetadata;
+}
+
 #pragma mark Finish
 
 - (void)finishWithError:(NSError *)errorOrNil {
@@ -277,7 +299,7 @@
 // The first one (metadataHandler), when the response headers are received.
 // The second one (completionHandler), whenever the RPC finishes for any reason.
 - (void)invokeCallWithMetadataHandler:(void(^)(NSDictionary *))metadataHandler
-                    completionHandler:(void(^)(NSError *))completionHandler {
+                    completionHandler:(void(^)(NSError *, NSDictionary *))completionHandler {
   // TODO(jcanizales): Add error handlers for async failures
   [_wrappedCall startBatchWithOperations:@[[[GRPCOpRecvMetadata alloc]
                                             initWithHandler:metadataHandler]]];
@@ -287,16 +309,26 @@
 
 - (void)invokeCall {
   __weak GRPCCall *weakSelf = self;
-  [self invokeCallWithMetadataHandler:^(NSDictionary *metadata) {
-    // Response metadata received.
+  [self invokeCallWithMetadataHandler:^(NSDictionary *headers) {
+    // Response headers received.
     GRPCCall *strongSelf = weakSelf;
     if (strongSelf) {
-      strongSelf.responseMetadata = metadata;
+      [strongSelf->_responseMetadata addEntriesFromDictionary:headers];
       [strongSelf startNextRead];
     }
-  } completionHandler:^(NSError *error) {
-    // TODO(jcanizales): Merge HTTP2 trailers into response metadata.
-    [weakSelf finishWithError:error];
+  } completionHandler:^(NSError *error, NSDictionary *trailers) {
+    GRPCCall *strongSelf = weakSelf;
+    if (strongSelf) {
+      [strongSelf->_responseMetadata addEntriesFromDictionary:trailers];
+
+      if (error) {
+        NSMutableDictionary *userInfo =
+            [NSMutableDictionary dictionaryWithDictionary:error.userInfo];
+        userInfo[kGRPCStatusMetadataKey] = strongSelf->_responseMetadata;
+        error = [NSError errorWithDomain:error.domain code:error.code userInfo:userInfo];
+      }
+      [strongSelf finishWithError:error];
+    }
   }];
   // Now that the RPC has been initiated, request writes can start.
   [_requestWriter startWithWriteable:self];