Getting started with Cloud Endpoints for the App Engine flexible environment with ESP

Getting the sample code

Configuring Endpoints

You must have an OpenAPI document based on either OpenAPI 2.0 or OpenAPI 3.x that describes the surface of your apps and any authentication requirements. To learn more, see Supported OpenAPI versions.

You also need to add a Google-specific field that contains the URL for each app so that ESPv2 has the information it needs to invoke an app. If you are new to OpenAPI, see OpenAPI overview for more information.

swagger: "2.0" info:   description: "A simple Google Cloud Endpoints API example."   title: "Endpoints Example"   version: "1.0.0" host: "YOUR_PROJECT_ID.appspot.com" consumes: - "application/json" produces: - "application/json" schemes: - "https" paths:   "/echo":     post:       description: "Echo back a given message."       operationId: "echo"       produces:       - "application/json"       responses:         200:           description: "Echo"           schema:             $ref: "#/definitions/echoMessage"       parameters:       - description: "Message to echo"         in: body         name: message         required: true         schema:           $ref: "#/definitions/echoMessage"       security:       - api_key: []   "/auth/info/googlejwt":     get:       description: "Returns the requests' authentication information."       operationId: "auth_info_google_jwt"       produces:       - "application/json"       responses:         200:           description: "Authentication info."           schema:             $ref: "#/definitions/authInfoResponse"       x-security:       - google_jwt:           audiences:           # This must match the "aud" field in the JWT. You can add multiple           # audiences to accept JWTs from multiple clients.           - "echo.endpoints.sample.google.com"   "/auth/info/googleidtoken":     get:       description: "Returns the requests' authentication information."       operationId: "authInfoGoogleIdToken"       produces:       - "application/json"       responses:         200:           description: "Authenication info."           schema:             $ref: "#/definitions/authInfoResponse"       x-security:       - google_id_token:           audiences:           # Your OAuth2 client's Client ID must be added here. You can add           # multiple client IDs to accept tokens from multiple clients.           - "YOUR-CLIENT-ID"  definitions:   echoMessage:     type: "object"     properties:       message:         type: "string"   authInfoResponse:     properties:       id:         type: "string"       email:         type: "string"  securityDefinitions:   # This section configures basic authentication with an API key.   api_key:     type: "apiKey"     name: "key"     in: "query"   # This section configures authentication using Google API Service Accounts   # to sign a json web token. This is mostly used for server-to-server   # communication.   google_jwt:     authorizationUrl: ""     flow: "implicit"     type: "oauth2"     # This must match the 'iss' field in the JWT.     x-google-issuer: "jwt-client.endpoints.sample.google.com"     # Update this with your service account's email address.     x-google-jwks_uri: "https://www.googleapis.com/service_accounts/v1/jwk/YOUR-SERVICE-ACCOUNT-EMAIL"   # This section configures authentication using Google OAuth2 ID Tokens.   # ID Tokens can be obtained using OAuth2 clients, and can be used to access   # your API on behalf of a particular user.   google_id_token:     authorizationUrl: ""     flow: "implicit"     type: "oauth2"     x-google-issuer: "https://accounts.google.com"     x-google-jwks_uri: "https://www.googleapis.com/oauth2/v1/certs"

This tutorial uses a Google-specific extension to the OpenAPI specification that lets you configure the service name. The method for specifying the service name depends on which version of the OpenAPI spec you are using.

host: YOUR_PROJECT_ID.appspot.com

servers: - url: https://YOUR_PROJECT_ID.appspot.com   x-google-endpoint: {}

Deploying the Endpoints configuration

To deploy the Endpoints configuration, you use the gcloud endpoints services deploy command. This command uses Service Management to create a managed service.

To deploy the Endpoints configuration:

1. Make sure you are in the directory where your openapi.yaml configuration file is located.
2. Upload the configuration and create a managed service:

    gcloud endpoints services deploy openapi.yaml 

The gcloud command then calls the Service Management API to create a managed service with the name that you specified in the host or servers.url field of the openapi.yaml file. Service Management configures the service according to the settings in the openapi.yaml file. When you make changes to openapi.yaml, you must redeploy the file to update the Endpoints service.

As it is creating and configuring the service, Service Management outputs information to the terminal. You can safely ignore the warnings about the paths in the openapi.yaml file not requiring an API key. When it finishes configuring the service, Service Management displays a message with the service configuration ID and the service name, similar to the following:

 Service Configuration [2017-02-13r0] uploaded for service [example-project-12345.appspot.com] 

In the preceding example, 2017-02-13r0 is the service configuration ID, and example-project-12345.appspot.com is the Endpoints service. The service configuration ID consists of a date stamp followed by a revision number. If you deploy the openapi.yaml file again on the same day, the revision number is incremented in the service configuration ID. You can view the Endpoints service configuration on the Endpoints > Services page in the Google Cloud console.

If you get an error message, see Troubleshooting Endpoints configuration deployment.

Checking required services

In most cases, the gcloud endpoints services deploy command enables these required services. However, the gcloud command completes successfully but doesn't enable the required services in the following circumstances:

• If you used a third-party application such as Terraform, and you don't include these services.

• You deployed the Endpoints configuration to an existing Google Cloud project in which these services were explicitly disabled.

Use the following command to confirm that the required services are enabled:

gcloud services list

If you do not see the required services listed, enable them:

gcloud services enable servicemanagement.googleapis.com gcloud services enable servicecontrol.googleapis.com

Also enable your Endpoints service:

gcloud services enable ENDPOINTS_SERVICE_NAME

To determine the ENDPOINTS_SERVICE_NAME you can either:

• After deploying the Endpoints configuration, go to the Endpoints page in the Cloud console. The list of possible ENDPOINTS_SERVICE_NAME are shown under the Service name column.

• For OpenAPI, the ENDPOINTS_SERVICE_NAME is what you specified in the host field of your OpenAPI spec. For gRPC, the ENDPOINTS_SERVICE_NAME is what you specified in the name field of your gRPC Endpoints configuration.

For more information about the gcloud commands, see gcloud services.

Deploying the API backend

So far you have deployed the OpenAPI document to Service Management, but you haven't yet deployed the code that serves the API backend. This section walks you through deploying the sample API and ESP to App Engine.

To deploy the API backend:

1. Add your service name to the app.yaml file:
   Java

   Open the endpoints/getting-started/src/main/appengine/app.yaml file.

   endpoints_api_service:   # The following values are to be replaced by information from the output of   # 'gcloud endpoints services deploy openapi-appengine.yaml' command.   name: ENDPOINTS-SERVICE-NAME   rollout_strategy: managed

   Python

   Open the endpoints/getting-started/app.yaml file.

   endpoints_api_service:   # The following values are to be replaced by information from the output of   # 'gcloud endpoints services deploy openapi-appengine.yaml' command.   name: ENDPOINTS-SERVICE-NAME   rollout_strategy: managed

   Go

   Open the endpoints/getting-started/app.yaml file.

   endpoints_api_service:   # The following values are to be replaced by information from the output of   # 'gcloud endpoints services deploy openapi-appengine.yaml' command.   name: ENDPOINTS-SERVICE-NAME   rollout_strategy: managed

   PHP

   Open the endpoints/getting-started/app.yaml file.

   endpoints_api_service:   # The following values are to be replaced by information from the output of   # 'gcloud endpoints services deploy openapi-appengine.yaml' command. If you have   # previously run the deploy command, you can list your existing configuration   # ids using the 'configs list' command as follows:   #   #     gcloud endpoints configs list --service=YOUR-PROJECT-ID.appspot.com   #   name: ENDPOINTS-SERVICE-NAME   rollout_strategy: managed

   Ruby

   Open the endpoints/getting-started/app.yaml file.

   endpoints_api_service:   # The following values are to be replaced by information from the output of   # 'gcloud endpoints services deploy openapi-appengine.yaml' command.   name: ENDPOINTS-SERVICE-NAME   rollout_strategy: managed

   NodeJS

   Open the endpoints/getting-started/app.yaml file.

   endpoints_api_service:   # The following values are to be replaced by information from the output of   # 'gcloud endpoints services deploy openapi-appengine.yaml' command.   name: ENDPOINTS-SERVICE-NAME   rollout_strategy: managed

   Replace ENDPOINTS-SERVICE-NAME with the name of your Endpoints service. This is the same name that you configured in the host field of your OpenAPI document. For example:

   endpoints_api_service:   name: example-project-12345.appspot.com   rollout_strategy: managed

   The rollout_strategy: managed option configures ESP to use the latest deployed service configuration. When you specify this option, up to 5 minutes after you deploy a new service configuration, ESP detects the change and automatically begins using it. We recommend that you specify this option instead of a specific configuration ID for ESP to use.

2. Save the app.yaml file.

Because the endpoints_api_service section is included in the app.yaml file, the gcloud app deploy command deploys and configures ESP in a separate container to your App Engine flexible environment. All request traffic is routed through ESP, and it proxies requests and responses to and from the container running your backend server code.

3. Make sure you are in the directory where your openapi.yaml configuration file is located.
4. Run the following command to deploy the sample API and ESP to App Engine:
Java
Deploy using Maven:
 mvn appengine:stage gcloud app deploy target/appengine-staging 
Python
gcloud app deploy
Go
gcloud app deploy
PHP
gcloud app deploy
Ruby
gcloud app deploy
NodeJS
gcloud app deploy

The gcloud app deploy command creates a DNS record in the format YOUR_PROJECT_ID.appspot.com, which you use when you send requests to the API. We recommend that you wait a few minutes before sending requests to your API while App Engine completely initializes.

If you get an error message, see Troubleshooting App Engine flexible deployment.

For more information, see Deploying the API backend.

Sending requests to the API

Now that the service is running on App Engine you can send requests to it.

Create an API key and set an environment variable

The sample code requires an API key. To simplify the request, you set an environment variable for the API key.

1. In the same Google Cloud project that you used for your API, create an API key on the API credentials page. If you want to create an API key in a different Google Cloud project, see Enabling an API in your Google Cloud project.

   Go to the Credentials page

2. Click Create credentials, and then select API key.
3. Copy the key to the clipboard.
4. Click Close.
5. On your local computer, paste the API key to assign it to an environment variable:
   • In Linux or macOS: export ENDPOINTS_KEY=AIza...
   • In Windows PowerShell: $Env:ENDPOINTS_KEY="AIza..."

Send the request

The API echoes back the message that you send it, and responds with the following:

{   "message": "hello world" } 

If you didn't get a successful response, see Troubleshooting response errors.

You just deployed and tested an API in Endpoints!

Tracking API activity

1. View the activity graphs for your API in the Endpoints page.

   Go to the Endpoints Services page

   It might take a few moments for the request to be reflected in the graphs.

2. Look at the request logs for your API in the Logs Explorer page.

   Go to the Logs Explorer page