Merge pull request #18330 from rmstar/uitestflake

Fix GrpcIosTestUITests flake and add some debug logging

src/objective-c/manual_tests/GrpcIosTest.xcodeproj/xcshareddata/xcschemes/GrpcIosTest.xcscheme

@@ -0,0 +1,101 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1010"
+   version = "1.3">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "5EDA907A220DF0BC0046D27A"
+               BuildableName = "GrpcIosTest.app"
+               BlueprintName = "GrpcIosTest"
+               ReferencedContainer = "container:GrpcIosTest.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES">
+      <Testables>
+         <TestableReference
+            skipped = "NO">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "B0C18CA3222DEF140002B502"
+               BuildableName = "GrpcIosTestUITests.xctest"
+               BlueprintName = "GrpcIosTestUITests"
+               ReferencedContainer = "container:GrpcIosTest.xcodeproj">
+            </BuildableReference>
+         </TestableReference>
+      </Testables>
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "5EDA907A220DF0BC0046D27A"
+            BuildableName = "GrpcIosTest.app"
+            BlueprintName = "GrpcIosTest"
+            ReferencedContainer = "container:GrpcIosTest.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+      <AdditionalOptions>
+      </AdditionalOptions>
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "5EDA907A220DF0BC0046D27A"
+            BuildableName = "GrpcIosTest.app"
+            BlueprintName = "GrpcIosTest"
+            ReferencedContainer = "container:GrpcIosTest.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+      <AdditionalOptions>
+      </AdditionalOptions>
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Release"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "5EDA907A220DF0BC0046D27A"
+            BuildableName = "GrpcIosTest.app"
+            BlueprintName = "GrpcIosTest"
+            ReferencedContainer = "container:GrpcIosTest.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>

src/objective-c/manual_tests/GrpcIosTestUITests/GrpcIosTestUITests.m

@@ -19,6 +19,7 @@
 #import <XCTest/XCTest.h>
 
 NSTimeInterval const kWaitTime = 30;
+int const kNumIterations = 1;
 
 @interface GrpcIosTestUITests : XCTestCase
 @end
@@ -32,16 +33,27 @@ NSTimeInterval const kWaitTime = 30;
   self.continueAfterFailure = NO;
   [[[XCUIApplication alloc] init] launch];
   testApp = [[XCUIApplication alloc] initWithBundleIdentifier:@"io.grpc.GrpcIosTest"];
+  [testApp activate];
+  // Reset RPC counter
+  [self pressButton:@"Reset counter"];
+
   settingsApp = [[XCUIApplication alloc] initWithBundleIdentifier:@"com.apple.Preferences"];
   [settingsApp activate];
+  [NSThread sleepForTimeInterval:1];
   // Go back to the first page of Settings.
   XCUIElement *backButton = settingsApp.navigationBars.buttons.firstMatch;
-  while (backButton.exists) {
+  while (backButton.exists && backButton.isHittable) {
+    NSLog(@"Tapping back button");
     [backButton tap];
   }
   XCTAssert([settingsApp.navigationBars[@"Settings"] waitForExistenceWithTimeout:kWaitTime]);
+  NSLog(@"Turning off airplane mode");
   // Turn off airplane mode
   [self setAirplaneMode:NO];
+
+  // Turn on wifi
+  NSLog(@"Turning on wifi");
+  [self setWifi:YES];
 }
 
 - (void)tearDown {
@@ -49,14 +61,25 @@ NSTimeInterval const kWaitTime = 30;
 
 - (void)doUnaryCall {
   [testApp activate];
-  [testApp.buttons[@"Unary call"] tap];
+  [self pressButton:@"Unary call"];
 }
 
-- (void)doStreamingCall {
+- (void)do10UnaryCalls {
   [testApp activate];
-  [testApp.buttons[@"Start streaming call"] tap];
-  [testApp.buttons[@"Send Message"] tap];
-  [testApp.buttons[@"Stop streaming call"] tap];
+  [self pressButton:@"10 Unary calls"];
+}
+
+- (void)pressButton:(NSString *)name {
+  // Wait for button to be visible
+  while (![testApp.buttons[name] exists] || ![testApp.buttons[name] isHittable]) {
+    [NSThread sleepForTimeInterval:1];
+  }
+  // Wait until all events in run loop have been processed
+  while (CFRunLoopRunInMode(kCFRunLoopDefaultMode, 0.1, true) == kCFRunLoopRunHandledSource)
+    ;
+
+  NSLog(@"Pressing button: %@", name);
+  [testApp.buttons[name] tap];
 }
 
 - (void)expectCallSuccess {
@@ -71,41 +94,81 @@ NSTimeInterval const kWaitTime = 30;
   [settingsApp activate];
   XCUIElement *mySwitch = settingsApp.tables.element.cells.switches[@"Airplane Mode"];
   BOOL from = [(NSString *)mySwitch.value boolValue];
+  NSLog(@"Setting airplane from: %d to: %d", from, to);
   if (from != to) {
     [mySwitch tap];
-    // wait for gRPC to detect the change
-    sleep(10);
+    // wait for network change to finish
+    [NSThread sleepForTimeInterval:5];
   }
   XCTAssert([(NSString *)mySwitch.value boolValue] == to);
 }
+- (void)setWifi:(BOOL)to {
+  [settingsApp activate];
+  [settingsApp.tables.element.cells.staticTexts[@"Wi-Fi"] tap];
+  XCUIElement *wifiSwitch = settingsApp.tables.cells.switches[@"Wi-Fi"];
+  BOOL from = [(NSString *)wifiSwitch.value boolValue];
+  NSLog(@"Setting wifi from: %d to: %d", from, to);
+  if (from != to) {
+    [wifiSwitch tap];
+    // wait for wifi networks to be detected
+    [NSThread sleepForTimeInterval:10];
+  }
+  // Go back to the first page of Settings.
+  XCUIElement *backButton = settingsApp.navigationBars.buttons.firstMatch;
+  [backButton tap];
+}
+
+- (void)typeText:(NSString *)text inApp:(XCUIApplication *)app {
+  [app typeText:text];
+  // Wait until all events in run loop have been processed
+  while (CFRunLoopRunInMode(kCFRunLoopDefaultMode, 0.1, true) == kCFRunLoopRunHandledSource)
+    ;
+}
 
-- (void)testBackgroundBeforeUnaryCall {
+- (int)getRandomNumberBetween:(int)min max:(int)max {
+  return min + arc4random_uniform((max - min + 1));
+}
+
+- (void)testBackgroundBeforeCall {
+  NSLog(@"%s", __func__);
   // Open test app
   [testApp activate];
-
   // Send test app to background
   [XCUIDevice.sharedDevice pressButton:XCUIDeviceButtonHome];
-  sleep(5);
+
+  // Wait a bit
+  int sleepTime = [self getRandomNumberBetween:5 max:10];
+  NSLog(@"Sleeping for %d seconds", sleepTime);
+  [NSThread sleepForTimeInterval:sleepTime];
 
   // Bring test app to foreground and make a unary call. Call should succeed
   [self doUnaryCall];
   [self expectCallSuccess];
 }
 
-- (void)testBackgroundBeforeStreamingCall {
-  // Open test app
+- (void)testBackgroundDuringStreamingCall {
+  NSLog(@"%s", __func__);
+  // Open test app and start a streaming call
   [testApp activate];
+  [self pressButton:@"Start streaming call"];
 
   // Send test app to background
   [XCUIDevice.sharedDevice pressButton:XCUIDeviceButtonHome];
-  sleep(5);
+
+  // Wait a bit
+  int sleepTime = [self getRandomNumberBetween:5 max:10];
+  NSLog(@"Sleeping for %d seconds", sleepTime);
+  [NSThread sleepForTimeInterval:sleepTime];
 
   // Bring test app to foreground and make a streaming call. Call should succeed.
-  [self doStreamingCall];
+  [testApp activate];
+  [self pressButton:@"Send Message"];
+  [self pressButton:@"Stop streaming call"];
   [self expectCallSuccess];
 }
 
-- (void)testUnaryCallAfterNetworkFlap {
+- (void)testCallAfterNetworkFlap {
+  NSLog(@"%s", __func__);
   // Open test app and make a unary call. Channel to server should be open after this.
   [self doUnaryCall];
   [self expectCallSuccess];
@@ -119,56 +182,150 @@ NSTimeInterval const kWaitTime = 30;
   [self expectCallSuccess];
 }
 
-- (void)testStreamingCallAfterNetworkFlap {
+- (void)testCallWhileNetworkDown {
+  NSLog(@"%s", __func__);
   // Open test app and make a unary call. Channel to server should be open after this.
   [self doUnaryCall];
   [self expectCallSuccess];
 
-  // Toggle airplane mode on and off
+  // Turn on airplane mode
   [self setAirplaneMode:YES];
+  // Turn off wifi
+  [self setWifi:NO];
+
+  // Unary call should fail
+  [self doUnaryCall];
+  [self expectCallFailed];
+
+  // Turn off airplane mode
   [self setAirplaneMode:NO];
+  // Turn on wifi
+  [self setWifi:YES];
 
-  [self doStreamingCall];
+  // Unary call should succeed
+  [self doUnaryCall];
   [self expectCallSuccess];
 }
 
-- (void)testUnaryCallWhileNetworkDown {
+- (void)testSwitchApp {
+  NSLog(@"%s", __func__);
   // Open test app and make a unary call. Channel to server should be open after this.
   [self doUnaryCall];
   [self expectCallSuccess];
 
-  // Turn on airplane mode
-  [self setAirplaneMode:YES];
+  // Send test app to background
+  [XCUIDevice.sharedDevice pressButton:XCUIDeviceButtonHome];
 
-  // Unary call should fail
+  // Open safari and goto a URL
+  XCUIApplication *safari =
+      [[XCUIApplication alloc] initWithBundleIdentifier:@"com.apple.mobilesafari"];
+  [safari activate];
+  // Ensure that safari is running in the foreground
+  XCTAssert([safari waitForState:XCUIApplicationStateRunningForeground timeout:5]);
+  // Move cursor to address bar
+  [safari.buttons[@"URL"] tap];
+  // Wait for keyboard to appear
+  [NSThread sleepForTimeInterval:2];
+  // Enter URL
+  [self typeText:@"http://maps.google.com" inApp:safari];
+  // Presses return key
+  [self typeText:@"\n" inApp:safari];
+  // Wait a bit
+  int sleepTime = [self getRandomNumberBetween:5 max:10];
+  NSLog(@"Sleeping for %d seconds", sleepTime);
+  [NSThread sleepForTimeInterval:sleepTime];
+
+  // Make another unary call
   [self doUnaryCall];
+  [self expectCallSuccess];
+}
+
+- (void)testNetworkFlapDuringStreamingCall {
+  NSLog(@"%s", __func__);
+  // Open test app and make a unary call. Channel to server should be open after this.
+  [self doUnaryCall];
+  [self expectCallSuccess];
+  // Start streaming call and send a message
+  [self pressButton:@"Start streaming call"];
+  [self pressButton:@"Send Message"];
+
+  // Toggle network on and off
+  [self setAirplaneMode:YES];
+  [self setWifi:NO];
+  [self setAirplaneMode:NO];
+  [self setWifi:YES];
+
+  [testApp activate];
+  // We expect the call to have failed because the network flapped
   [self expectCallFailed];
+}
 
-  // Turn off airplane mode
+- (void)testConcurrentCalls {
+  NSLog(@"%s", __func__);
+
+  // Press button to start 10 unary calls
+  [self do10UnaryCalls];
+
+  // Toggle airplane mode on and off
+  [self setAirplaneMode:YES];
   [self setAirplaneMode:NO];
 
-  // Unary call should succeed
+  // 10 calls should have completed
+  [testApp activate];
+  XCTAssert([testApp.staticTexts[@"Calls completed: 10"] waitForExistenceWithTimeout:kWaitTime]);
+}
+
+- (void)invokeTest {
+  for (int i = 0; i < kNumIterations; i++) {
+    [super invokeTest];
+  }
+}
+
+- (void)testUnaryCallTurnOffWifi {
+  NSLog(@"%s", __func__);
+  // Open test app and make a unary call. Channel to server should be open after this.
+  [self doUnaryCall];
+  [self expectCallSuccess];
+
+  // Turn off wifi
+  [self setWifi:NO];
+
+  // Phone should switch to cellular connection, call should succeed
+  [self doUnaryCall];
+  [self expectCallSuccess];
+
+  // Turn on wifi
+  [self setWifi:YES];
+
+  // Call should succeed after turning wifi back on
   [self doUnaryCall];
   [self expectCallSuccess];
 }
 
-- (void)testStreamingCallWhileNetworkDown {
+- (void)testStreamingCallTurnOffWifi {
+  NSLog(@"%s", __func__);
   // Open test app and make a unary call. Channel to server should be open after this.
   [self doUnaryCall];
   [self expectCallSuccess];
 
-  // Turn on airplane mode
-  [self setAirplaneMode:YES];
+  // Start streaming call and send a message
+  [self pressButton:@"Start streaming call"];
+  [self pressButton:@"Send Message"];
+
+  // Turn off wifi
+  [self setWifi:NO];
 
-  // Streaming call should fail
-  [self doStreamingCall];
+  // Phone should switch to cellular connection, this results in the call failing
+  [testApp activate];
+  [self pressButton:@"Stop streaming call"];
   [self expectCallFailed];
 
-  // Turn off airplane mode
-  [self setAirplaneMode:NO];
+  // Turn on wifi
+  [self setWifi:YES];
 
-  // Unary call should succeed
-  [self doStreamingCall];
+  // Call should succeed after turning wifi back on
+  [self doUnaryCall];
   [self expectCallSuccess];
 }
+
 @end

src/objective-c/manual_tests/Main.storyboard

@@ -1,11 +1,11 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="14313.18" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="BYZ-38-t0r">
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="14460.31" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="BYZ-38-t0r">
     <device id="retina4_7" orientation="portrait">
         <adaptation id="fullscreen"/>
     </device>
     <dependencies>
         <deployment identifier="iOS"/>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="14283.14"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="14460.20"/>
         <capability name="Safe area layout guides" minToolsVersion="9.0"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
@@ -26,16 +26,8 @@
                                     <action selector="tapStreamingCallStart:" destination="BYZ-38-t0r" eventType="touchUpInside" id="6tF-9u-Gew"/>
                                 </connections>
                             </button>
-                            <button opaque="NO" contentMode="scaleToFill" fixedFrame="YES" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="dxG-ib-Xoa">
-                                <rect key="frame" x="197" y="221" width="132" height="30"/>
-                                <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
-                                <state key="normal" title="Stop streaming call"/>
-                                <connections>
-                                    <action selector="tapStreamingCallStop:" destination="BYZ-38-t0r" eventType="touchUpInside" id="QLQ-yw-wlZ"/>
-                                </connections>
-                            </button>
                             <button opaque="NO" contentMode="scaleToFill" fixedFrame="YES" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="ay7-K7-Lez">
-                                <rect key="frame" x="48" y="71" width="69" height="30"/>
+                                <rect key="frame" x="35" y="71" width="69" height="30"/>
                                 <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
                                 <state key="normal" title="Unary call"/>
                                 <connections>
@@ -43,13 +35,51 @@
                                 </connections>
                             </button>
                             <button opaque="NO" contentMode="scaleToFill" fixedFrame="YES" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="Sq5-O5-fiK">
-                                <rect key="frame" x="213" y="147" width="101" height="30"/>
+                                <rect key="frame" x="196" y="147" width="101" height="30"/>
                                 <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
                                 <state key="normal" title="Send Message"/>
                                 <connections>
                                     <action selector="tapStreamingCallSend:" destination="BYZ-38-t0r" eventType="touchUpInside" id="Qz0-PB-akd"/>
                                 </connections>
                             </button>
+                            <label opaque="NO" userInteractionEnabled="NO" tag="1" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" fixedFrame="YES" text="" textAlignment="natural" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="7JI-bR-X8r">
+                                <rect key="frame" x="134" y="323" width="98" height="56"/>
+                                <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
+                                <fontDescription key="fontDescription" type="system" pointSize="17"/>
+                                <nil key="textColor"/>
+                                <nil key="highlightedColor"/>
+                            </label>
+                            <label opaque="NO" userInteractionEnabled="NO" tag="2" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" fixedFrame="YES" text="Calls completed: 0" textAlignment="natural" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="Wwu-kV-w7R">
+                                <rect key="frame" x="128" y="418" width="180" height="56"/>
+                                <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
+                                <fontDescription key="fontDescription" type="system" pointSize="17"/>
+                                <nil key="textColor"/>
+                                <nil key="highlightedColor"/>
+                            </label>
+                            <button opaque="NO" contentMode="scaleToFill" fixedFrame="YES" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="q8d-Mi-SAJ">
+                                <rect key="frame" x="35" y="147" width="96" height="30"/>
+                                <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
+                                <state key="normal" title="10 Unary calls"/>
+                                <connections>
+                                    <action selector="tap10UnaryCalls:" destination="BYZ-38-t0r" eventType="touchUpInside" id="pY2-Rq-hVn"/>
+                                </connections>
+                            </button>
+                            <button opaque="NO" contentMode="scaleToFill" fixedFrame="YES" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="Csm-o1-8eh">
+                                <rect key="frame" x="35" y="221" width="96" height="30"/>
+                                <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
+                                <state key="normal" title="Reset counter"/>
+                                <connections>
+                                    <action selector="resetCounter:" destination="BYZ-38-t0r" eventType="touchUpInside" id="InY-SX-R6H"/>
+                                </connections>
+                            </button>
+                            <button opaque="NO" contentMode="scaleToFill" fixedFrame="YES" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="dxG-ib-Xoa">
+                                <rect key="frame" x="196" y="221" width="132" height="30"/>
+                                <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
+                                <state key="normal" title="Stop streaming call"/>
+                                <connections>
+                                    <action selector="tapStreamingCallStop:" destination="BYZ-38-t0r" eventType="touchUpInside" id="QLQ-yw-wlZ"/>
+                                </connections>
+                            </button>
                         </subviews>
                         <color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                         <viewLayoutGuide key="safeArea" id="6Tk-OE-BBY"/>
@@ -57,6 +87,7 @@
                 </viewController>
                 <placeholder placeholderIdentifier="IBFirstResponder" id="dkx-z0-nzr" sceneMemberID="firstResponder"/>
             </objects>
+            <point key="canvasLocation" x="128.80000000000001" y="132.68365817091455"/>
         </scene>
     </scenes>
 </document>

src/objective-c/manual_tests/ViewController.m

@@ -27,33 +27,36 @@ NSString *const kRemoteHost = @"grpc-test.sandbox.googleapis.com";
 const int32_t kMessageSize = 100;
 
 @interface ViewController : UIViewController<GRPCProtoResponseHandler>
-@property(strong, nonatomic) UILabel *fromLabel;
+@property(strong, nonatomic) UILabel *callStatusLabel;
+@property(strong, nonatomic) UILabel *callCountLabel;
 @end
 
 @implementation ViewController {
   RMTTestService *_service;
   dispatch_queue_t _dispatchQueue;
   GRPCStreamingProtoCall *_call;
+  int _calls_completed;
 }
 - (instancetype)init {
   self = [super init];
+  _calls_completed = 0;
   return self;
 }
 
 - (void)viewDidLoad {
   [super viewDidLoad];
   _dispatchQueue = dispatch_queue_create(NULL, DISPATCH_QUEUE_SERIAL);
-  _fromLabel = [[UILabel alloc] initWithFrame:CGRectMake(100, 500, 200, 20)];
-  _fromLabel.textColor = [UIColor blueColor];
-  _fromLabel.backgroundColor = [UIColor whiteColor];
-  [self.view addSubview:_fromLabel];
+  _callStatusLabel = (UILabel *)[self.view viewWithTag:1];
+  _callCountLabel = (UILabel *)[self.view viewWithTag:2];
 }
 
-- (IBAction)tapUnaryCall:(id)sender {
+- (void)startUnaryCall {
   if (_service == nil) {
     _service = [RMTTestService serviceWithHost:kRemoteHost];
   }
-  self->_fromLabel.text = @"";
+  dispatch_async(dispatch_get_main_queue(), ^{
+    self->_callStatusLabel.text = @"";
+  });
 
   // Set up request proto message
   RMTSimpleRequest *request = [RMTSimpleRequest message];
@@ -63,14 +66,43 @@ const int32_t kMessageSize = 100;
 
   GRPCUnaryProtoCall *call =
       [_service unaryCallWithMessage:request responseHandler:self callOptions:nil];
+
   [call start];
 }
 
+- (IBAction)tapUnaryCall:(id)sender {
+  NSLog(@"In tapUnaryCall");
+  [self startUnaryCall];
+}
+
+- (IBAction)tap10UnaryCalls:(id)sender {
+  NSLog(@"In tap10UnaryCalls");
+  dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^(void) {
+    // Background thread
+    for (int i = 0; i < 10; ++i) {
+      [self startUnaryCall];
+      [NSThread sleepForTimeInterval:0.5];
+    }
+  });
+}
+
+- (IBAction)resetCounter:(id)sender {
+  _calls_completed = 0;
+  dispatch_async(dispatch_get_main_queue(), ^{
+    self->_callCountLabel.text =
+        [NSString stringWithFormat:@"Calls completed: %d", self->_calls_completed];
+    self->_callStatusLabel.text = @"";
+  });
+}
+
 - (IBAction)tapStreamingCallStart:(id)sender {
+  NSLog(@"In tapStreamingCallStart");
   if (_service == nil) {
     _service = [RMTTestService serviceWithHost:kRemoteHost];
   }
-  self->_fromLabel.text = @"";
+  dispatch_async(dispatch_get_main_queue(), ^{
+    self->_callStatusLabel.text = @"";
+  });
 
   // Set up request proto message
   RMTStreamingOutputCallRequest *request = RMTStreamingOutputCallRequest.message;
@@ -83,10 +115,10 @@ const int32_t kMessageSize = 100;
   [call start];
   _call = call;
   // display something to confirm the tester the call is started
-  NSLog(@"Started streaming call");
 }
 
 - (IBAction)tapStreamingCallSend:(id)sender {
+  NSLog(@"In tapStreamingCallSend");
   if (_call == nil) return;
 
   RMTStreamingOutputCallRequest *request = RMTStreamingOutputCallRequest.message;
@@ -99,6 +131,7 @@ const int32_t kMessageSize = 100;
 }
 
 - (IBAction)tapStreamingCallStop:(id)sender {
+  NSLog(@"In tapStreamingCallStop");
   if (_call == nil) return;
 
   [_call finish];
@@ -118,13 +151,18 @@ const int32_t kMessageSize = 100;
   NSLog(@"Recv trailing metadata: %@, error: %@", trailingMetadata, error);
   if (error == nil) {
     dispatch_async(dispatch_get_main_queue(), ^{
-      self->_fromLabel.text = @"Call done";
+      self->_callStatusLabel.text = @"Call done";
     });
   } else {
     dispatch_async(dispatch_get_main_queue(), ^{
-      self->_fromLabel.text = @"Call failed";
+      self->_callStatusLabel.text = @"Call failed";
     });
   }
+  ++_calls_completed;
+  dispatch_async(dispatch_get_main_queue(), ^{
+    self->_callCountLabel.text =
+        [NSString stringWithFormat:@"Calls completed: %d", self->_calls_completed];
+  });
 }
 
 - (dispatch_queue_t)dispatchQueue {