Implement client-side Firebase Cloud Functions locations

packages/firebase-functions/README.md

@@ -48,6 +48,41 @@ firebase()
 	});
 ```
 
+## Regional Cloud Functions
+Cloud Functions are _regional_, which means the infrastructure that runs your Cloud Function is located in specific regions.
+
+By default, functions run in the _us-central1_ region. View the [supported regions](https://firebase.google.com/docs/functions/locations).
+
+To run functions in a different region, after initializing Firebase App set the region using _firebase().app().functions(region)_.
+
+Regional function endpoint example (using _europe-west2_ region ):
+```ts
+// Deployed HTTPS callable
+exports.listProducts = functions.region("europe-west2").https.onCall(() => {
+	return [
+		/* ... */
+		// Return some data
+	];
+});
+```
+
+To access the regional function endpoint:
+```ts
+import { firebase } from '@nativescript/firebase-core';
+import '@nativescript/firebase-functions';
+
+firebase().initializeApp();
+firebase().app().functions("europe-west2");
+
+firebase()
+	.functions()
+	.httpsCallable('listProducts')()
+	.then((response) => {
+		setProducts(response.data);
+		setLoading(false);
+	});
+```
+
 ## Using an emulator
 
 Whilst developing your application with Cloud Functions, it is possible to run the functions inside of a local emulator.

packages/firebase-functions/index.android.ts

@@ -3,11 +3,10 @@ import {
   HttpsCallable,
   HttpsCallableOptions,
   HttpsErrorCode,
-  IFunctions,
+  IFunctions
 } from "./common";
 import {deserialize, firebase, FirebaseApp, serialize} from "@nativescript/firebase-core";
 
-
 let defaultFunctions: Functions;
 
 const fb = firebase();
@@ -24,6 +23,31 @@ Object.defineProperty(fb, 'functions', {
 	},
 	writable: false,
 });
+/**
+  Firebase Functions Region - Region for which to run HttpsCallable method
+  Set parameter using firebase().app().functions(regionOrCustomDomain: string)
+  @see https://firebase.google.com/docs/reference/android/com/google/firebase/functions/FirebaseFunctions
+  @note If not set, default region is used ("us-central1")
+  */
+let defaultRegionOrCustomDomain: string;
+/**
+  Add 'functions' method to FirebaseApp class
+  @see https://firebase.google.com/docs/reference/node/firebase.app.App
+  @see https://firebase.google.com/docs/functions/locations
+  @param regionOrCustomDomain(string)(Optional): Name of the region for which to Functions results
+  @return Functions
+  */
+const fbApp = FirebaseApp;
+Object.defineProperty(fbApp.prototype, 'functions', {
+	value: (regionOrCustomDomain?: string) => {
+		defaultRegionOrCustomDomain = regionOrCustomDomain;
+    if (!defaultFunctions) {
+      defaultFunctions = new Functions();
+    }
+		return defaultFunctions;
+	},
+	writable: false,
+});
 
 
 function errorToCode(error: com.google.firebase.functions.FirebaseFunctionsException.Code) {
@@ -130,13 +154,19 @@ export class Functions implements IFunctions {
 
   constructor(app?: FirebaseApp) {
     if (app?.native) {
-      this.#native = com.google.firebase.functions.FirebaseFunctions.getInstance(app.native);
+      this.#native = defaultRegionOrCustomDomain
+        ? com.google.firebase.functions.FirebaseFunctions.getInstance(app.native, defaultRegionOrCustomDomain)
+        : com.google.firebase.functions.FirebaseFunctions.getInstance(app.native);
     } else {
       if(defaultFunctions){
         return defaultFunctions;
       }
       defaultFunctions = this;
-      this.#native = com.google.firebase.functions.FirebaseFunctions.getInstance();
+      // If defaultRegionOrCustomDomain is set, get FirebaseFunctions instance using that parameter
+      // @see https://firebase.google.com/docs/functions/locations#client-side_location_selection_for_callable_functions
+      this.#native = defaultRegionOrCustomDomain
+         ? com.google.firebase.functions.FirebaseFunctions.getInstance(defaultRegionOrCustomDomain)
+         : com.google.firebase.functions.FirebaseFunctions.getInstance();
     }
   }
 
@@ -162,7 +192,7 @@ export class Functions implements IFunctions {
   }
 
   useEmulator(host: string, port: number) {
-    this.native.useEmulator(host, port);
+    this.native.useEmulator(host === 'localhost' ? '10.0.2.2' : host, port);
   }
 
   get native() {

packages/firebase-functions/index.d.ts

@@ -26,9 +26,22 @@ export declare class Functions implements IFunctions {
 }
 
 declare module '@nativescript/firebase-core' {
+
 	export interface Firebase extends FirebaseFunctions {}
+	// Add 'functions' method to FirebaseApp
+	export interface FirebaseApp extends FirebaseFunctionsApp {}
 }
 
 export interface FirebaseFunctions {
 	static functions(app?: FirebaseApp): Functions;
 }
+/**
+	Add Region (Android & iOS) or Custom Domain (iOS only) to Firebase Functions HTTPS call
+	@param regionOrCustomDomain (string) (optional): Region (Android or iOS) or Custom Domain (iOS only)
+	@return Functions
+	@see Supported Regions: https://firebase.google.com/docs/functions/locations
+	@example firebase().app().functions("us-central1")
+	*/
+export interface FirebaseFunctionsApp {
+	static functions(regionOrCustomDomain?: string): Functions;
+}

packages/firebase-functions/index.ios.ts

@@ -3,7 +3,7 @@ import {
   HttpsCallable,
   HttpsCallableOptions,
   HttpsErrorCode,
-  IFunctions,
+  IFunctions
 } from "./common";
 import {deserialize, firebase, FirebaseApp, serialize} from "@nativescript/firebase-core";
 
@@ -23,6 +23,34 @@ Object.defineProperty(fb, 'functions', {
 	},
 	writable: false,
 });
+/**
+  Firebase Functions Region - Region for which to run HttpsCallable method
+  Set parameter using firebase().app().functions(regionOrCustomDomain: string)
+  @link https://firebase.google.com/docs/reference/node/firebase.app.App
+  @link https://firebase.google.com/docs/reference/ios/firebasefunctions/api/reference/Classes/FIRFunctions
+  @note If not set, default region is used ('us-central1')
+  */
+let defaultRegionOrCustomDomain: string;
+/**
+  Add 'functions' method to FirebaseApp class
+  @param regionOrCustomDomain(string)(Optional): Name of the Region or Custom Domain for which to Functions results
+  @return Functions
+  @see FirebaseFunctions
+  @link https://firebase.google.com/docs/reference/ios/firebasefunctions/api/reference/Classes/FIRFunctions
+  @see Supported Regions
+  @see https://firebase.google.com/docs/functions/locations
+  */
+const fbApp = FirebaseApp;
+Object.defineProperty(fbApp.prototype, 'functions', {
+	value: (regionOrCustomDomain?: string) => {
+		defaultRegionOrCustomDomain = regionOrCustomDomain;
+    if (!defaultFunctions) {
+      defaultFunctions = new Functions();
+    }
+		return defaultFunctions;
+	},
+	writable: false,
+});
 
 function errorToCode(error: NSError) {
   let code = HttpsErrorCode.UNKNOWN;
@@ -115,13 +143,29 @@ export class Functions implements IFunctions {
 
   constructor(app?: FirebaseApp) {
     if (app?.native) {
-      this.#native = FIRFunctions.functionsForApp(app.native);
+      if(defaultRegionOrCustomDomain){
+        this.#native = isRegion(defaultRegionOrCustomDomain) // Check whether a Region has been set
+          ? FIRFunctions.functionsForAppRegion(app.native, defaultRegionOrCustomDomain)  // @see https://firebase.google.com/docs/reference/ios/firebasefunctions/api/reference/Classes/FIRFunctions#+functionsforapp:region:
+          : isCustomDomain(defaultRegionOrCustomDomain) // Check whether using a Custom Domain has been set
+            ? FIRFunctions.functionsForAppCustomDomain(app.native, defaultRegionOrCustomDomain) // @see https://firebase.google.com/docs/reference/ios/firebasefunctions/api/reference/Classes/FIRFunctions#+functionsforapp:customdomain:
+            : FIRFunctions.functionsForApp(app.native); // @see https://firebase.google.com/docs/reference/ios/firebasefunctions/api/reference/Classes/FIRFunctions#+functionsforapp:
+      } else {
+        this.#native = FIRFunctions.functionsForApp(app.native); // @see https://firebase.google.com/docs/reference/ios/firebasefunctions/api/reference/Classes/FIRFunctions#+functionsforapp:
+      }
     } else {
       if(defaultFunctions){
         return defaultFunctions;
       }
       defaultFunctions = this;
-      this.#native = FIRFunctions.functions();
+      if(defaultRegionOrCustomDomain){
+        this.#native = isRegion(defaultRegionOrCustomDomain) // Check whether a Region has been set
+          ? FIRFunctions.functionsForRegion(defaultRegionOrCustomDomain) // @see https://firebase.google.com/docs/reference/ios/firebasefunctions/api/reference/Classes/FIRFunctions#+functionsforregion:
+          : isCustomDomain(defaultRegionOrCustomDomain) // Check whether using a Custom Domain has been set
+            ? FIRFunctions.functionsForCustomDomain(defaultRegionOrCustomDomain) // @see https://firebase.google.com/docs/reference/ios/firebasefunctions/api/reference/Classes/FIRFunctions#+functionsforcustomdomain:
+            : FIRFunctions.functions(); // @see https://firebase.google.com/docs/reference/ios/firebasefunctions/api/reference/Classes/FIRFunctions#+functions
+      } else {
+        this.#native = FIRFunctions.functions(); // @see https://firebase.google.com/docs/reference/ios/firebasefunctions/api/reference/Classes/FIRFunctions#+functions
+      }
     }
   }
 
@@ -178,3 +222,20 @@ export class Functions implements IFunctions {
     return this.#app;
   }
 }
+/**
+  Check whether a regionOrCustomDomain string is a Region for the http trigger, such as “us-central1”.
+  @param regionOrCustomDomain(string): Text to parse
+  @return boolean: TRUE if a Region; FALSE if not
+  */
+function isRegion(regionOrCustomDomain: string): boolean{
+  const elems = regionOrCustomDomain.split('.');
+  return elems.length === 1 ? true : false;
+}
+/**
+  Check whether a regionOrCustomDomain string is a Custom Domain for the http trigger, such as “https://mydomain.com”
+  @param regionOrCustomDomain(string): Text to parse
+  @return boolean: TRUE if a CustomDomain; FALSE if not
+  */
+function isCustomDomain(regionOrCustomDomain: string): boolean{
+  return !isRegion(regionOrCustomDomain);
+}