[[["容易理解","easyToUnderstand","thumb-up"],["確實解決了我的問題","solvedMyProblem","thumb-up"],["其他","otherUp","thumb-up"]],[["缺少我需要的資訊","missingTheInformationINeed","thumb-down"],["過於複雜/步驟過多","tooComplicatedTooManySteps","thumb-down"],["過時","outOfDate","thumb-down"],["翻譯問題","translationIssue","thumb-down"],["示例/程式碼問題","samplesCodeIssue","thumb-down"],["其他","otherDown","thumb-down"]],["上次更新時間:2024-10-16 (世界標準時間)。"],[],[],null,["# Get started using App Check in C++ apps\n\n\u003cbr /\u003e\n\nThis page shows you how to enable App Check in a C++ app, using the\ndefault providers: Play Integrity on Android, and Device Check or App Attest on\nApple platforms. When you enable App Check, you help ensure that\nonly your app can access your project's Firebase resources. See an\n[Overview](/docs/app-check) of this feature.\n\n1. Set up your Firebase project\n-------------------------------\n\n1. [Add Firebase to your C++ project](/docs/cpp/setup) if you haven't\n already done so.\n\n2. Register your apps to use App Check with the Play Integrity, Device Check,\n or App Attest providers in the\n [**Project Settings \\\u003e App Check**](https://console.firebase.google.com/project/_/appcheck)\n section of the Firebase console.\n\n You usually need to register all of your project's apps, because once you\n enable enforcement for a Firebase product, only registered apps will be able\n to access the product's backend resources.\n\n For detailed instructions on how to register with each provider, refer to\n the Android and iOS specific documentation.\n3. **Optional**: In the app registration settings, set a custom time-to-live\n (TTL) for App Check tokens issued by the provider. You can set the TTL\n to any value between 30 minutes and 7 days. When changing this value, be\n aware of the following tradeoffs:\n\n - Security: Shorter TTLs provide stronger security, because it reduces the window in which a leaked or intercepted token can be abused by an attacker.\n - Performance: Shorter TTLs mean your app will perform attestation more frequently. Because the app attestation process adds latency to network requests every time it's performed, a short TTL can impact the performance of your app.\n - Quota and cost: Shorter TTLs and frequent re-attestation deplete your quota faster, and for paid services, potentially cost more. See [Quotas \\& limits](/docs/app-check#quotas_limits).\n\n The default TTL\n is reasonable for most apps. Note that the App Check library refreshes\n tokens at approximately half the TTL duration.\n\n2. Add the App Check library to your app\n----------------------------------------\n\nInclude the App Check library in your set of dependencies, following\n[the setup instructions](/docs/cpp/setup#add-sdks) for App Check.\n\n3. Initialize App Check\n-----------------------\n\nAdd the following initialization code to your app so that it runs before you\nuse any Firebase services including any creation of Firebase Apps. \n\n### Android\n\n1. Include the header file for `firebase::app_check`:\n\n ```c++\n #include \"firebase/app_check.h\"\n ```\n2. Initialize the App Check library with the Play Integrity provider:\n\n firebase::app_check::AppCheck::SetAppCheckProviderFactory(\n firebase::app_check::PlayIntegrityProviderFactory::GetInstance());\n\n### iOS+\n\n1. Include the header file for `firebase::app_check`:\n\n ```c++\n #include \"firebase/app_check.h\"\n ```\n2. Initialize the App Check library with the Device Check or App Attest\n provider:\n\n firebase::app_check::AppCheck::SetAppCheckProviderFactory(\n firebase::app_check::DeviceCheckProviderFactory::GetInstance());\n\nNext steps\n----------\n\nOnce the App Check library is installed in your app, start distributing the\nupdated app to your users.\n\nThe updated client app will begin sending App Check tokens along with every\nrequest it makes to Firebase, but Firebase products will not require the tokens\nto be valid until you enable enforcement in the App Check section of the\nFirebase console.\n\n### Monitor metrics and enable enforcement\n\nBefore you enable enforcement, however, you should make sure that doing so won't\ndisrupt your existing legitimate users. On the other hand, if you're seeing\nsuspicious use of your app resources, you might want to enable enforcement\nsooner.\n\nTo help make this decision, you can look at App Check metrics for the\nservices you use:\n\n- [Monitor App Check request metrics](/docs/app-check/monitor-metrics) for Realtime Database, Cloud Firestore, and Cloud Storage.\n- [Monitor App Check request metrics for Cloud Functions](/docs/app-check/monitor-functions-metrics).\n\n### Enable App Check enforcement\n\nWhen you understand how App Check will affect your users and you're ready to\nproceed, you can enable App Check enforcement:\n\n- [Enable App Check enforcement](/docs/app-check/enable-enforcement) for Realtime Database, Cloud Firestore, and Cloud Storage.\n- [Enable App Check enforcement for Cloud Functions](/docs/app-check/cloud-functions).\n\n### Use App Check in debug environments\n\nIf, after you have registered your app for App Check, you want to run your\napp in an environment that App Check would normally not classify as valid,\nsuch as on desktop, an emulator during development, or from a continuous\nintegration (CI) environment, you can create a debug build of your app that\nuses the App Check debug provider instead of a real attestation provider.\n\nSee [Use App Check with the debug provider in C++ apps](/docs/app-check/cpp/debug-provider)."]]