extend-service-extension-java

flowchart LR
   CL[Game Client]
   subgraph "Extend Service Extension App (you are here)"
   GW["gRPC Gateway"]
   SV["gRPC Server"]
   end
   CL --- GW
   GW --- SV

AccelByte Gaming Services (AGS) capabilities can be extended with Extend Service Extension apps. An Extend Service Extension app is essentially a custom REST API service built using a combination of gRPC Gateway and gRPC Server.

Overview

This repository serves as a template project for an Extend Service Extension app written in Java. You can clone this repository and start creating endpoints by editing the gRPC proto file and implementing your own logic.

By using this repository as a template project, you will get basic authentication and authorization implemented out-of-the-box. You will also get some instrumentation for observability so that metrics, traces, and logs will be available when the app is deployed. Since the source code is included, you can customize them according to your needs.

As an example to get you started, this template project contains a sample custom guild service which has two endpoints to create and get guild progress data.

Prerequisites

1. Windows 11 WSL2 or Linux Ubuntu 22.04 with the following installed.

   a. Bash

   bash --version
   
   GNU bash, version 5.1.16(1)-release (x86_64-pc-linux-gnu)
   ...
   

   b. Make

   • To install from Ubuntu repository, run: sudo apt update && sudo apt install make

   make --version
   
   GNU Make 4.3
   ...
   

   c. Docker (Docker Engine v23.0+)

   • To install from Ubuntu repository, run: sudo apt update && sudo apt install docker.io
   • Add your user to docker group: sudo usermod -aG docker $USER
   • Log out and log back in so that the changes take effect

   docker version
   
   ...
   Server: Docker Desktop
    Engine:
     Version:          24.0.5
   ...
   

   d. JDK 17

   • To install from Ubuntu repository, run: sudo apt update && sudo apt install openjdk-17-jdk

   java --version
   
   openjdk 17.0.10 2024-01-16
   ...
   

2. Access to AGS environment.

   a. Base URL:

   • For Starter tier e.g. https://spaceshooter.prod.gamingservices.accelbyte.io
   • For Premium tier e.g. https://dev.accelbyte.io

   b. Create a Game Namespace if you don't have one yet. Keep the Namespace ID.

   c. Create an OAuth Client with confidential client type with the following permissions. Keep the Client ID and Client Secret.

   • For AGS Premium customers:
     • ADMIN:ROLE [READ] to validate access token and permissions
     • ADMIN:NAMESPACE:{namespace}:CLOUDSAVE:RECORD [CREATE,READ,UPDATE,DELETE] to create, read, update, and delete cloudsave records
   • For AGS Starter customers:
     • IAM -> Roles (Read)
     • Cloud Save -> Game Records (Create, Read, Update, Delete)

Setup

To be able to run the sample custom guild service, you will need to follow these setup steps.

1. Create a docker compose .env file by copying the content of .env.template file.

   ⚠️ The host OS environment variables have higher precedence compared to .env file variables: If the variables in .env file do not seem to take effect properly, check if there are host OS environment variables with the same name. See documentation about docker compose environment variables precedence for more details.

2. Fill in the required environment variables in .env file as shown below.

   AB_BASE_URL=https://test.accelbyte.io     # Base URL of AccelByte Gaming Services demo environment
   AB_CLIENT_ID='xxxxxxxxxx'                 # Client ID from the Prerequisites section
   AB_CLIENT_SECRET='xxxxxxxxxx'             # Client Secret from the Prerequisites section
   AB_NAMESPACE='xxxxxxxxxx'                 # Namespace ID from the Prerequisites section
   PLUGIN_GRPC_SERVER_AUTH_ENABLED=true      # Enable or disable access token and permission validation
   BASE_PATH='/guild'                        # The base path used for the app
   

   :info: In this sample app, PLUGIN_GRPC_SERVER_AUTH_ENABLED is true by default: If it is set to false, the endpoint permission.action and permission.resource validation will be disabled and the endpoint can be accessed without a valid access token. This option is provided for development purpose only. For more information, see creating-new-endpoint.

Building

To build this sample app, use the following command.

make build

Running

To (build and) run this sample app in a container, use the following command.

docker compose up --build

Testing

Test in Local Development Environment

The sample custom guild service included in this template project can be tested locally using Swagger UI.

1. Run this Extend Service Extension sample app by using the command below.

   docker compose up --build

2. If PLUGIN_GRPC_SERVER_AUTH_ENABLED is true, you will need the a user access token to access the REST API service. You can generate the user access token using getusertoken.sh shell script. To run it, you will need to set the following environment variables.

   export AB_BASE_URL='http://test.accelbyte.io'    # Your environment's domain Base URL
   export AB_CLIENT_ID='xxxxxxxxxx'                 # Client ID from the Prerequisites section
   export AB_CLIENT_SECRET='xxxxxxxxxx'             # Client Secret from the Prerequisites section

   Then use the following command to run the script to get the user access token.

   # The <username> and <password> are the user's credential to access AGS.
   bash getusertoken.sh <username> <password>

   :info: Make sure the user has a role which contains this permission: ADMIN:NAMESPACE:{namespace}:CLOUDSAVE:RECORD [CREATE,READ,UPDATE,DELETE].

3. The REST API service can then be tested by opening Swagger UI at http://localhost:8000/guild/apidocs/. Use this to create an API request to try the endpoints.

   :info: Depending on the envar you set for BASE_PATH, the service will have different service URL. This how it's the formatted http://localhost:8000/<base_path>

   

   To authorize Swagger UI, click on "Authorize" button on right side.

   

   Popup will show, input "Bearer <user's access token>" in Value field for Bearer (apiKey). Then click "Authorize" to save the user's access token.

Test Observability

To be able to see the how the observability works in this sample app locally, there are few things that need be setup before performing tests.

1. Uncomment loki logging driver in docker-compose.yaml

    # logging:
    #   driver: loki
    #   options:
    #     loki-url: http://host.docker.internal:3100/loki/api/v1/push
    #     mode: non-blocking
    #     max-buffer-size: 4m
    #     loki-retries: "3"
   

   ⚠️ Make sure to install docker loki plugin beforehand: Otherwise, this sample app will not be able to run. This is required so that container logs can flow to the loki service within grpc-plugin-dependencies stack. Use this command to install docker loki plugin: docker plugin install grafana/loki-docker-driver:latest --alias loki --grant-all-permissions.

2. Clone and run grpc-plugin-dependencies stack alongside this sample app. After this, Grafana will be accessible at http://localhost:3000.

   git clone https://github.com/AccelByte/grpc-plugin-dependencies.git
   cd grpc-plugin-dependencies
   docker compose up
   

   ❗ More information about grpc-plugin-dependencies is available here.

3. Perform testing. For example, by following Test in Local Development Environment.

Deploying

To deploy this app to AGS, follow the steps below.

1. Create a new Extend Service Extension App on Admin Portal. Keep the Repository URI.

2. Download and setup extend-helper-cli (only if it has not been done previously).

3. Perform docker login with extend-helper-cli using the following command.

   extend-helper-cli dockerlogin --namespace <my-game> --app <my-app> --login
   

   ❗ For your convenience, the above extend-helper-cli command can also be copied from Repository Authentication Command under the corresponding app detail page.

4. Build and push sample app docker image to AccelByte ECR using the following command.

   make imagex_push IMAGE_TAG=v0.0.1 REPO_URL=xxxxxxxxxx.dkr.ecr.us-west-2.amazonaws.com/accelbyte/justice/development/extend/xxxxxxxxxx/xxxxxxxxxx
   

   ❗ The REPO_URL is obtained from step 1: It can be found under 'Repository URI' in the app detail.

5. Open Admin Portal, go to Extend -> Service Extension. And then select the extend app.

6. To deploy selected image tag, click Image Version History and select desired image tag to be deployed.

7. Click Deploy Image, confirm the deployment and go back to App Detail by clicking Cancel.

8. Wait until app status is running.

For more information on how to deploy an Extend Service Extension app, see here.

Next Step

Proceed to modify this template project and create your own endpoints. See here for more details.