Add a couple of new small Functions APIs. (#1434)

* Add a Functions constructor that allows setting a region.
* Add a method to set an emulator origin to use.
* Update the changelog

2 files changed, 21 insertions, 11 deletions

diff --git a/Functions/FirebaseFunctions/FIRFunctions.m b/Functions/FirebaseFunctions/FIRFunctions.m
index 274d058..5a67d86 100644
--- a/Functions/FirebaseFunctions/FIRFunctions.m
+++ b/Functions/FirebaseFunctions/FIRFunctions.m
@@ -43,9 +43,8 @@ NSString *const kFUNInstanceIDTokenHeader = @"Firebase-Instance-ID-Token";
   FUNSerializer *_serializer;
   // A factory for getting the metadata to include with function calls.
   FUNContextProvider *_contextProvider;
-  // For testing only. If this is set, functions will be called against localhost instead of
-  // Firebase.
-  BOOL _useLocalhost;
+  // For testing only. If this is set, functions will be called against it instead of Firebase.
+  NSString *_emulatorOrigin;
 }
 
 /**
@@ -86,13 +85,17 @@ NSString *const kFUNInstanceIDTokenHeader = @"Firebase-Instance-ID-Token";
     _region = [region copy];
     _serializer = [[FUNSerializer alloc] init];
     _contextProvider = [[FUNContextProvider alloc] initWithApp:app];
-    _useLocalhost = NO;
+    _emulatorOrigin = nil;
   }
   return self;
 }
 
 - (void)useLocalhost {
-  _useLocalhost = YES;
+  [self useFunctionsEmulatorOrigin:@"http://localhost:5005"];
+}
+
+- (void)useFunctionsEmulatorOrigin:(NSString *)origin {
+  _emulatorOrigin = origin;
 }
 
 - (NSString *)URLWithName:(NSString *)name {
@@ -103,8 +106,8 @@ NSString *const kFUNInstanceIDTokenHeader = @"Firebase-Instance-ID-Token";
   if (!projectID) {
     FUNThrowInvalidArgument(@"FIRFunctions app projectID cannot be nil.");
   }
-  if (_useLocalhost) {
-    return [NSString stringWithFormat:@"http://localhost:5005/%@/%@/%@", projectID, _region, name];
+  if (_emulatorOrigin) {
+    return [NSString stringWithFormat:@"%@/%@/%@/%@", _emulatorOrigin, projectID, _region, name];
   }
   return
       [NSString stringWithFormat:@"https://%@-%@.cloudfunctions.net/%@", _region, projectID, name];
@@ -166,7 +169,7 @@ NSString *const kFUNInstanceIDTokenHeader = @"Firebase-Instance-ID-Token";
   }
 
   // Override normal security rules if this is a local test.
-  if (_useLocalhost) {
+  if (_emulatorOrigin) {
     fetcher.allowLocalhostRequest = YES;
     fetcher.allowedInsecureSchemes = @[ @"http" ];
   }
diff --git a/Functions/FirebaseFunctions/Public/FIRFunctions.h b/Functions/FirebaseFunctions/Public/FIRFunctions.h
index d01175c..98d7a67 100644
--- a/Functions/FirebaseFunctions/Public/FIRFunctions.h
+++ b/Functions/FirebaseFunctions/Public/FIRFunctions.h
@@ -42,7 +42,7 @@ NS_SWIFT_NAME(Functions)
  * Creates a Cloud Functions client with the default app and given region.
  * @param region The region for the http trigger, such as "us-central1".
  */
-// + (instancetype)functionsForRegion:(NSString *)region NS_SWIFT_NAME(functions(region:));
++ (instancetype)functionsForRegion:(NSString *)region NS_SWIFT_NAME(functions(region:));
 
 /**
  * Creates a Cloud Functions client with the given app and region.
@@ -51,8 +51,8 @@ NS_SWIFT_NAME(Functions)
  */
 // clang-format off
 // because it incorrectly breaks this NS_SWIFT_NAME.
-// + (instancetype)functionsForApp:(FIRApp *)app
-//                         region:(NSString *)region NS_SWIFT_NAME(functions(app:region:));
++ (instancetype)functionsForApp:(FIRApp *)app
+                         region:(NSString *)region NS_SWIFT_NAME(functions(app:region:));
 // clang-format on
 
 /**
@@ -61,6 +61,13 @@ NS_SWIFT_NAME(Functions)
  */
 - (FIRHTTPSCallable *)HTTPSCallableWithName:(NSString *)name NS_SWIFT_NAME(httpsCallable(_:));
 
+/**
+ * Changes this instance to point to a Cloud Functions emulator running locally.
+ * See https://firebase.google.com/docs/functions/local-emulator
+ * @param origin The origin of the local emulator, such as "http://localhost:5005".
+ */
+- (void)useFunctionsEmulatorOrigin:(NSString *)origin NS_SWIFT_NAME(useFunctionsEmulator(origin:));
+
 @end
 
 NS_ASSUME_NONNULL_END