API キーは、割り当て、課金、モニタリングのためにGoogle Cloud プロジェクトを識別する単純な文字列です。デベロッパーは、Google Cloud コンソールでプロジェクトの API キーを生成し、このキーをクエリ パラメータとして、またはリクエスト ヘッダーとしてすべての API 呼び出しに埋め込みます。
API 構成で API キーを必須として指定した場合、API Gateway はその API キーを使用して、関連付けられた Google Cloud プロジェクトを検索します。現在お使いの Google Cloud プロジェクトまたは API が有効になっている他のGoogle Cloud プロジェクトで API キーが生成されていない場合、API ゲートウェイ はリクエストを拒否します。
API キーを作成するか、 Google Cloud プロジェクト内ですでに使用可能な API キーを表示するには、[API とサービス] > [認証情報] ページに移動します。
API キーは、デフォルトでは制限されません。制限されていないキーは、誰でもどこからでも使用できるため安全ではありません。可能な限り、API の制限を追加することをおすすめします。API の制限では、API キーを使用した呼び出しを許可する API を指定します。本番環境アプリケーションで使用されるすべての API キーには、API 制限を追加する必要があります。
API の制限を追加するには:
API 構成に記載されている API のタイトルを確認します。次の例では、API のタイトルは My Example Config です。
# openapi.yamlswagger:'2.0'info:title:My Example Configdescription:Sample API on API Gatewayversion:1.0.0...
Google Cloud コンソールで、[API とサービス] > [認証情報] ページに移動します。
[[["わかりやすい","easyToUnderstand","thumb-up"],["問題の解決に役立った","solvedMyProblem","thumb-up"],["その他","otherUp","thumb-up"]],[["わかりにくい","hardToUnderstand","thumb-down"],["情報またはサンプルコードが不正確","incorrectInformationOrSampleCode","thumb-down"],["必要な情報 / サンプルがない","missingTheInformationSamplesINeed","thumb-down"],["翻訳に関する問題","translationIssue","thumb-down"],["その他","otherDown","thumb-down"]],["最終更新日 2025-04-22 UTC。"],[[["\u003cp\u003eAPI keys are simple strings used to identify a Google Cloud project for quota, billing, and monitoring in API Gateway.\u003c/p\u003e\n"],["\u003cp\u003eAPI Gateway requires API keys generated within your Google Cloud project, or projects where your API is enabled, to authorize requests.\u003c/p\u003e\n"],["\u003cp\u003eWhile useful for features like quotas, API keys are vulnerable to man-in-the-middle attacks and should not be the sole form of authentication for sensitive data.\u003c/p\u003e\n"],["\u003cp\u003eEnabling API key support for a service requires using the \u003ccode\u003egcloud services enable MANAGED_SERVICE_NAME\u003c/code\u003e command, specifying the managed service's name.\u003c/p\u003e\n"],["\u003cp\u003eFor security, API keys should be restricted to specific APIs through the Google Cloud console's \u003cstrong\u003eAPIs & Services > Credentials\u003c/strong\u003e page, ensuring they are not used by unauthorized parties.\u003c/p\u003e\n"]]],[],null,["# Using API Keys\n==============\n\nThis page describes how to utilize API keys in API Gateway.\n\nAn API key is a simple string that identifies a\nGoogle Cloud project for quota, billing, and monitoring purposes. A\ndeveloper generates an API key in a project in the Google Cloud console and\nembeds that key in every call to your API as a query parameter or in a request header.\n\nIf you specify an API key requirement in your API config,\nAPI Gateway uses the API key to look up the associated Google Cloud project. API Gateway rejects requests unless\nthe API key was generated in your Google Cloud project or within other\nGoogle Cloud projects in which your API has been enabled.\n| **Note:** Unlike credentials that use short-lived tokens or signed requests, API keys function as part of the API request. As a result, API keys are vulnerable to [man-in-the-middle attacks](https://wikipedia.org/wiki/Man-in-the-middle_attack) and may not be as secure as other authentication credentials. You can use API keys in addition to one of the other [supported forms of authentication](/api-gateway/docs/authentication-method), but we do not recommend using *only* API keys when API calls contain sensitive data.\n\nTo create an API key, or view API keys already available within your Google Cloud project, go to the **APIs \\& Services** \\\u003e **Credentials** page.\n\n[Go to Credentials](https://console.cloud.google.com/apis/credentials)\n\n\u003cbr /\u003e\n\n### Use case\n\nTo use API Gateway features such as\n[quotas](/api-gateway/docs/quotas-overview), you can pass in an API\nkey so that API Gateway can identify the Google Cloud project\nthat the client application is associated with.\n\n### About API key authentication for API Gateway\n\nIf you are using an API key for authentication, you must first enable API key support\nfor your service.\n\nEnter the following command: \n\n```\ngcloud services enable MANAGED_SERVICE_NAME\n```\n\n\u003cbr /\u003e\n\nThe \u003cvar translate=\"no\"\u003eMANAGED_SERVICE_NAME\u003c/var\u003e specifies the name of the managed service created when you deployed the API. You can find this name in the Managed Service column for your API on the APIs landing page in the console. Alternatively, you can find this name in the `Managed service` property when using the `gcloud api-gateway apis describe` command.\n\nFor example: \n\n```\ngcloud services enable my-api-a12bcd345e67f89g0h.apigateway.my-project.cloud.goog\n```\n\n### Restricting API keys\n\nAPI keys are unrestricted by default. Unrestricted keys are insecure because\nthey can be used by anyone from anywhere. We recommend that you add *API restrictions* where possible.\nAPI restrictions specify which APIs can be called using the API key. All API keys used by production applications should have API restrictions.\n\nTo add API restrictions:\n\n1. Find the title of the API as noted in your API Config. In the following example, the API title is `My Example Config`:\n\n ```yaml\n # openapi.yaml\n swagger: '2.0'\n info:\n title: My Example Config\n description: Sample API on API Gateway\n version: 1.0.0\n ...\n ```\n2. In the Google Cloud console, go to the **APIs \\& Services** \\\u003e **Credentials** page.\n\n [Go to Credentials](https://console.cloud.google.com/apis/credentials)\n\n \u003cbr /\u003e\n\n3. Select the name of the API key you wish to use for your API.\n\n4. In the **API restrictions** section of the API key detail page, click **Restrict key**.\n\n5. Select the API that your API key will be used to access from the dropdown list of available APIs. For example, if\n using the example config above, select `My Example Config`.\n\n6. Click **Save**.\n\nYour restriction should take effect momentarily."]]
