Cloud Functions for Firebase 用戶端 SDK 可讓您直接透過 或 Firebase 應用程式如要以這種方式從應用程式呼叫函式,請編寫及部署 Cloud Functions 中的 HTTP 可呼叫函式,以及 然後新增用戶端邏輯,從應用程式呼叫該函式。
請牢記,HTTP 可呼叫函式很類似, 並非完全與 HTTP 函式相同。如要使用 HTTP 呼叫函式,您必須 將平台的用戶端 SDK 與 或導入通訊協定可通話項目具備這些鍵 與 HTTP 函式的差異
- 使用可呼叫元件時,Firebase Authentication 權杖、FCM 權杖和 App Check 權杖 (如果有的話) 會自動納入要求中。
- 觸發條件會自動反序列化要求主體並驗證驗證權杖。
Cloud Functions 第 2 代以上的 Firebase SDK 可與這些 Firebase 用戶端互通 支援 HTTPS 呼叫函式的 SDK 最低版本:
- Apple 平台適用的 Firebase SDK 11.0.0
- Firebase Android 21.0.0 版 SDK
- Firebase 模組化 Web SDK 9.7.0 版
針對在不支援
平台,請參閱 https.onCall
的通訊協定規格。本指南的其餘部分
瞭解如何編寫、部署及呼叫
適用於 Apple 平台、Android、網頁、C++ 和 Unity 的 HTTP 可呼叫函式。
編寫及部署可呼叫函式
本節的程式碼範例是以完整的 快速入門導覽課程範例 示範如何將要求傳送至伺服器端函式,並取得 使用其中一個用戶端 SDK 回應如要開始操作,請匯入 模組:
Node.js
// Dependencies for callable functions.
const {onCall, HttpsError} = require("firebase-functions/v2/https");
const {logger} = require("firebase-functions/v2");
// Dependencies for the addMessage function.
const {getDatabase} = require("firebase-admin/database");
const sanitizer = require("./sanitizer");
Python
# Dependencies for callable functions.
from firebase_functions import https_fn, options
# Dependencies for writing to Realtime Database.
from firebase_admin import db, initialize_app
為您的平台使用要求處理常式 (functions.https.onCall
)
或 on_call
)
來建立 HTTPS 可呼叫函式這個方法
使用要求參數:
Node.js
// Saves a message to the Firebase Realtime Database but sanitizes the
// text by removing swearwords.
exports.addmessage = onCall((request) => {
// ...
});
Python
@https_fn.on_call()
def addmessage(req: https_fn.CallableRequest) -> Any:
"""Saves a message to the Firebase Realtime Database but sanitizes the text
by removing swear words."""
request
參數包含從用戶端應用程式傳送的資料,以及驗證狀態等其他背景資訊。若是可呼叫函式,可將文字訊息儲存至 Realtime Database,
例如,data
可以包含訊息文字和驗證資訊
在 auth
中:
Node.js
// Message text passed from the client.
const text = request.data.text;
// Authentication / user information is automatically added to the request.
const uid = request.auth.uid;
const name = request.auth.token.name || null;
const picture = request.auth.token.picture || null;
const email = request.auth.token.email || null;
Python
# Message text passed from the client.
text = req.data["text"]
# Authentication / user information is automatically added to the request.
uid = req.auth.uid
name = req.auth.token.get("name", "")
picture = req.auth.token.get("picture", "")
email = req.auth.token.get("email", "")
可呼叫函式位置與位置之間的距離 發出呼叫的用戶端可能會造成網路延遲。為提高成效 請考慮指定函式位置,其中 並且務必將呼叫端的位置與位置對齊 在初始化 SDK 時設定 用戶端管理。
您可以選擇附加 App Check 認證來保護 偵測出遭濫用的後端資源,例如帳單詐欺或網路釣魚。詳情請見 為 Cloud Functions 啟用 App Check 強制執行功能。
正在傳回結果
如要將資料傳回用戶端,請傳回可採用 JSON 編碼的資料。適用對象 例如,傳回加總運算的結果:
Node.js
// returning result.
return {
firstNumber: firstNumber,
secondNumber: secondNumber,
operator: "+",
operationResult: firstNumber + secondNumber,
};
Python
return {
"firstNumber": first_number,
"secondNumber": second_number,
"operator": "+",
"operationResult": first_number + second_number
}
訊息文字範例中經過清理的文字都會傳回用戶端和 Realtime Database。在 Node.js 中 來非同步地使用 JavaScript 承諾:
Node.js
// Saving the new message to the Realtime Database.
const sanitizedMessage = sanitizer.sanitizeText(text); // Sanitize message.
return getDatabase().ref("/messages").push({
text: sanitizedMessage,
author: {uid, name, picture, email},
}).then(() => {
logger.info("New Message written");
// Returning the sanitized message to the client.
return {text: sanitizedMessage};
})
Python
# Saving the new message to the Realtime Database.
sanitized_message = sanitize_text(text) # Sanitize message.
db.reference("/messages").push({ # type: ignore
"text": sanitized_message,
"author": {
"uid": uid,
"name": name,
"picture": picture,
"email": email
}
})
print("New message written")
# Returning the sanitized message to the client.
return {"text": sanitized_message}
設定 CORS (跨源資源共享)
使用 cors
選項控管哪些來源可存取函式。
根據預設,可呼叫函式的 CORS 設定為允許所有來自 如要允許部分跨來源要求 (而非全部),請傳送 特定網域或規則運算式例如:
Node.js
const { onCall } = require("firebase-functions/v2/https");
exports.getGreeting = onCall(
{ cors: [/firebase\.com$/, "https://flutter.com"] },
(request) => {
return "Hello, world!";
}
);
如要禁止跨來源要求,請將 cors
政策設為 false
。
處理錯誤
為確保用戶端能取得實用的錯誤詳細資料,請從可呼叫的呼叫傳回錯誤
將 (或針對傳回 Promise 的 Node.js 傳回 Promise 遭拒) 的
functions.https.HttpsError
或 https_fn.HttpsError
。
錯誤的 code
屬性可以是 gRPC 中列出的其中一個值
狀態碼。
錯誤也包含 message
字串,預設
空字串且可能也設有選用的 details
欄位,以及
任意值如果函式擲回 HTTPS 錯誤以外的錯誤,
您的客戶收到了錯誤訊息 INTERNAL
和代碼
internal
。
例如,函式可能會擲回資料驗證和驗證錯誤 且錯誤訊息會傳回呼叫用戶端:
Node.js
// Checking attribute.
if (!(typeof text === "string") || text.length === 0) {
// Throwing an HttpsError so that the client gets the error details.
throw new HttpsError("invalid-argument", "The function must be called " +
"with one arguments \"text\" containing the message text to add.");
}
// Checking that the user is authenticated.
if (!request.auth) {
// Throwing an HttpsError so that the client gets the error details.
throw new HttpsError("failed-precondition", "The function must be " +
"called while authenticated.");
}
Python
# Checking attribute.
if not isinstance(text, str) or len(text) < 1:
# Throwing an HttpsError so that the client gets the error details.
raise https_fn.HttpsError(code=https_fn.FunctionsErrorCode.INVALID_ARGUMENT,
message=('The function must be called with one argument, "text",'
" containing the message text to add."))
# Checking that the user is authenticated.
if req.auth is None:
# Throwing an HttpsError so that the client gets the error details.
raise https_fn.HttpsError(code=https_fn.FunctionsErrorCode.FAILED_PRECONDITION,
message="The function must be called while authenticated.")
部署可呼叫函式
將已完成的可呼叫函式儲存在 index.js
中後,
會在您執行 firebase deploy
時與所有其他函式一起部署。
如果只要部署可呼叫的項目,請使用 --only
引數執行,如下所示
部分部署:
firebase deploy --only functions:addMessage
如果您在部署函式時遇到權限錯誤,請確認 您可以查看適當的身分與存取權管理角色 執行部署指令的使用者
設定用戶端開發環境
請確認符合所有必要條件,然後新增必要的依附元件,並 用戶端程式庫
iOS+
按照操作說明將 Firebase 新增至 Apple 應用程式。
使用 Swift Package Manager 安裝及管理 Firebase 依附元件。
- 在 Xcode 中保持開啟應用程式專案,然後前往「檔案」檔案 >新增套件。
- 在系統提示時,新增 Firebase Apple 平台 SDK 存放區:
- 選擇 Cloud Functions 程式庫。
- 在目標建構設定的「Other Linker Flags」部分中新增
-ObjC
標記。 - 完成後,Xcode 會自動開始解析並下載 複製到背景依附元件
https://github.com/firebase/firebase-ios-sdk.git
Web
- 請按照操作說明執行下列操作:
將 Firebase 新增至您的網頁應用程式。請務必執行
從終端機執行下列指令:
npm install firebase@10.13.1 --save
手動同時需要 Firebase 核心和 Cloud Functions:
import { initializeApp } from 'firebase/app'; import { getFunctions } from 'firebase/functions'; const app = initializeApp({ projectId: '### CLOUD FUNCTIONS PROJECT ID ###', apiKey: '### FIREBASE API KEY ###', authDomain: '### FIREBASE AUTH DOMAIN ###', }); const functions = getFunctions(app);
Android
請按照操作說明執行下列操作: 在您的 Android 應用程式中加入 Firebase。
在模組 (應用程式層級) Gradle 檔案中 (通常為
<project>/<app-module>/build.gradle.kts
或<project>/<app-module>/build.gradle
)、 新增 Android Cloud Functions 程式庫的依附元件。建議您使用 Firebase Android BoM敬上 管理程式庫版本管理dependencies { // Import the BoM for the Firebase platform implementation(platform("com.google.firebase:firebase-bom:33.2.0")) // Add the dependency for the Cloud Functions library // When using the BoM, you don't specify versions in Firebase library dependencies implementation("com.google.firebase:firebase-functions") }
只要使用 Firebase Android BoM, 應用程式一律會使用相容的 Firebase Android 程式庫版本。
(替代做法) 新增 Firebase 程式庫依附元件,「不使用」 BoM
如果選擇不使用 Firebase BoM,請指定各個 Firebase 程式庫版本 都屬於依附元件行
請注意,如果您在應用程式中使用多個 Firebase 程式庫,強烈建議您 建議使用 BoM 管理程式庫版本,確保所有版本 相容。
dependencies { // Add the dependency for the Cloud Functions library // When NOT using the BoM, you must specify versions in Firebase library dependencies implementation("com.google.firebase:firebase-functions:21.0.0") }
初始化用戶端 SDK
初始化 Cloud Functions 的執行個體:
Swift
lazy var functions = Functions.functions()
Objective-C
@property(strong, nonatomic) FIRFunctions *functions;
// ...
self.functions = [FIRFunctions functions];
Web
const app = initializeApp({
projectId: '### CLOUD FUNCTIONS PROJECT ID ###',
apiKey: '### FIREBASE API KEY ###',
authDomain: '### FIREBASE AUTH DOMAIN ###',
});
const functions = getFunctions(app);
Kotlin+KTX
private lateinit var functions: FirebaseFunctions // ... functions = Firebase.functions
Java
private FirebaseFunctions mFunctions; // ... mFunctions = FirebaseFunctions.getInstance();
呼叫函式
Swift
functions.httpsCallable("addMessage").call(["text": inputField.text]) { result, error in
if let error = error as NSError? {
if error.domain == FunctionsErrorDomain {
let code = FunctionsErrorCode(rawValue: error.code)
let message = error.localizedDescription
let details = error.userInfo[FunctionsErrorDetailsKey]
}
// ...
}
if let data = result?.data as? [String: Any], let text = data["text"] as? String {
self.resultField.text = text
}
}
Objective-C
[[_functions HTTPSCallableWithName:@"addMessage"] callWithObject:@{@"text": _inputField.text}
completion:^(FIRHTTPSCallableResult * _Nullable result, NSError * _Nullable error) {
if (error) {
if ([error.domain isEqual:@"com.firebase.functions"]) {
FIRFunctionsErrorCode code = error.code;
NSString *message = error.localizedDescription;
NSObject *details = error.userInfo[@"details"];
}
// ...
}
self->_resultField.text = result.data[@"text"];
}];
Web
var addMessage = firebase.functions().httpsCallable('addMessage');
addMessage({ text: messageText })
.then((result) => {
// Read result of the Cloud Function.
var sanitizedMessage = result.data.text;
});
Web
import { getFunctions, httpsCallable } from "firebase/functions";
const functions = getFunctions();
const addMessage = httpsCallable(functions, 'addMessage');
addMessage({ text: messageText })
.then((result) => {
// Read result of the Cloud Function.
/** @type {any} */
const data = result.data;
const sanitizedMessage = data.text;
});
Kotlin+KTX
private fun addMessage(text: String): Task<String> { // Create the arguments to the callable function. val data = hashMapOf( "text" to text, "push" to true, ) return functions .getHttpsCallable("addMessage") .call(data) .continueWith { task -> // This continuation runs on either success or failure, but if the task // has failed then result will throw an Exception which will be // propagated down. val result = task.result?.data as String result } }
Java
private Task<String> addMessage(String text) { // Create the arguments to the callable function. Map<String, Object> data = new HashMap<>(); data.put("text", text); data.put("push", true); return mFunctions .getHttpsCallable("addMessage") .call(data) .continueWith(new Continuation<HttpsCallableResult, String>() { @Override public String then(@NonNull Task<HttpsCallableResult> task) throws Exception { // This continuation runs on either success or failure, but if the task // has failed then getResult() will throw an Exception which will be // propagated down. String result = (String) task.getResult().getData(); return result; } }); }
Dart
final result = await FirebaseFunctions.instance.httpsCallable('addMessage').call(
{
"text": text,
"push": true,
},
);
_response = result.data as String;
C++
firebase::Future<firebase::functions::HttpsCallableResult> AddMessage(
const std::string& text) {
// Create the arguments to the callable function.
firebase::Variant data = firebase::Variant::EmptyMap();
data.map()["text"] = firebase::Variant(text);
data.map()["push"] = true;
// Call the function and add a callback for the result.
firebase::functions::HttpsCallableReference doSomething =
functions->GetHttpsCallable("addMessage");
return doSomething.Call(data);
}
Unity
private Task<string> addMessage(string text) {
// Create the arguments to the callable function.
var data = new Dictionary<string, object>();
data["text"] = text;
data["push"] = true;
// Call the function and extract the operation from the result.
var function = functions.GetHttpsCallable("addMessage");
return function.CallAsync(data).ContinueWith((task) => {
return (string) task.Result.Data;
});
}
處理用戶端上的錯誤
如果伺服器擲回錯誤,或出現 造成的承諾也遭到拒絕
如果函式傳回的錯誤屬於 function.https.HttpsError
類型,
則用戶端會從要求中,收到 code
、message
和 details
錯誤。
伺服器發生錯誤。否則,錯誤會包含訊息 INTERNAL
和
代碼 INTERNAL
。請參閱指南,瞭解如何
處理錯誤。
Swift
if let error = error as NSError? {
if error.domain == FunctionsErrorDomain {
let code = FunctionsErrorCode(rawValue: error.code)
let message = error.localizedDescription
let details = error.userInfo[FunctionsErrorDetailsKey]
}
// ...
}
Objective-C
if (error) {
if ([error.domain isEqual:@"com.firebase.functions"]) {
FIRFunctionsErrorCode code = error.code;
NSString *message = error.localizedDescription;
NSObject *details = error.userInfo[@"details"];
}
// ...
}
Web
var addMessage = firebase.functions().httpsCallable('addMessage');
addMessage({ text: messageText })
.then((result) => {
// Read result of the Cloud Function.
var sanitizedMessage = result.data.text;
})
.catch((error) => {
// Getting the Error details.
var code = error.code;
var message = error.message;
var details = error.details;
// ...
});
Web
import { getFunctions, httpsCallable } from "firebase/functions";
const functions = getFunctions();
const addMessage = httpsCallable(functions, 'addMessage');
addMessage({ text: messageText })
.then((result) => {
// Read result of the Cloud Function.
/** @type {any} */
const data = result.data;
const sanitizedMessage = data.text;
})
.catch((error) => {
// Getting the Error details.
const code = error.code;
const message = error.message;
const details = error.details;
// ...
});
Kotlin+KTX
addMessage(inputMessage) .addOnCompleteListener { task -> if (!task.isSuccessful) { val e = task.exception if (e is FirebaseFunctionsException) { val code = e.code val details = e.details } } }
Java
addMessage(inputMessage) .addOnCompleteListener(new OnCompleteListener<String>() { @Override public void onComplete(@NonNull Task<String> task) { if (!task.isSuccessful()) { Exception e = task.getException(); if (e instanceof FirebaseFunctionsException) { FirebaseFunctionsException ffe = (FirebaseFunctionsException) e; FirebaseFunctionsException.Code code = ffe.getCode(); Object details = ffe.getDetails(); } } } });
Dart
try {
final result =
await FirebaseFunctions.instance.httpsCallable('addMessage').call();
} on FirebaseFunctionsException catch (error) {
print(error.code);
print(error.details);
print(error.message);
}
C++
void OnAddMessageCallback(
const firebase::Future<firebase::functions::HttpsCallableResult>& future) {
if (future.error() != firebase::functions::kErrorNone) {
// Function error code, will be kErrorInternal if the failure was not
// handled properly in the function call.
auto code = static_cast<firebase::functions::Error>(future.error());
// Display the error in the UI.
DisplayError(code, future.error_message());
return;
}
const firebase::functions::HttpsCallableResult* result = future.result();
firebase::Variant data = result->data();
// This will assert if the result returned from the function wasn't a string.
std::string message = data.string_value();
// Display the result in the UI.
DisplayResult(message);
}
// ...
// ...
auto future = AddMessage(message);
future.OnCompletion(OnAddMessageCallback);
// ...
Unity
addMessage(text).ContinueWith((task) => {
if (task.IsFaulted) {
foreach (var inner in task.Exception.InnerExceptions) {
if (inner is FunctionsException) {
var e = (FunctionsException) inner;
// Function error code, will be INTERNAL if the failure
// was not handled properly in the function call.
var code = e.ErrorCode;
var message = e.ErrorMessage;
}
}
} else {
string result = task.Result;
}
});
建議做法:使用 App Check 防範濫用行為
請先啟用 App Check,再啟動應用程式 確保只有您的應用程式可以存取可呼叫的函式端點。