GitHub Actions workflow for Go Continuous Integration

Table of Contents

• Introduction
• My Workflow
• Submission Category
• Yaml File and Link to Code
• GitHub Action Workflow Run Output
• Additional Info
  • How to Add GitHub Actions workflow
  • How to Integrate Slack with GitHub Actions Workflow
  • Go Source Code Details
  • Go REST API Unit testing

Introduction

• I've created a GitHub action that performs the Go continuous integration process on the Go source code repository
• Interested Go developers and DevOps Engineers can use this workflow to create the Continuous Integration for their GitHub repo
• Created this workflow for the submission of actionshackathon21

Workflow Details

Go Continuous Integration workflow

• The workflow we created will be doing the Continuous Integration process on this repository.
• Whenever there is a code check-in happens on main branch, then CI workflow will be triggered
• Below are the details of this workflow
  • Code checkout into the workspace
  • Install Go and runs the Go linting process for doing code review
  • Get the build dependencies
  • Builds the code
  • Runs the Unit test, if it is success it moves to next stage
  • Docker image is created for the code and pushed into docker hub registry
  • Finally workflow posts the status of each step to a slack channel
• Here is the link to the GitHub actions workflow Yaml

Marketplace GitHub Actions used in this Workflow

I've leveraged existing actions available from GitHub Actions Marketplace

• actions/checkout@v2 - Action that is used to checkout code.
• reviewdog/action-golangci-lint@v2 - Go installation and linting action.
• mr-smithers-excellent/docker-build-push@v5 - Docker build and push action.
• act10ns/slack@v1 - Slack GitHub Action Integration action

Submission Category

• DIY Deployments

Yaml File and Link to Code

• GitHub Actions Workflow Yaml

name: Go_CI_Workflow

on:
  push:
    branches: [ main ]
  pull_request:
    branches: [ main ]

jobs:

  build:
    name: Build
    runs-on: ubuntu-latest
    steps:
    - name: Check out code to Build
      uses: actions/checkout@v2

    - name: Install Go and Run Code Linting
      id: Install-Go
      uses: reviewdog/action-golangci-lint@v2

    - name: Get dependencies to Build
      id: Get-dependencies-to-Build
      run: |
        go get -v -t -d ./...
        if [ -f Gopkg.toml ]; then
            curl https://raw.githubusercontent.com/golang/dep/master/install.sh | sh
            dep ensure
        fi

    - name: Build Code
      id: Build-Code
      run: |
        go build -v .

    - name: Unit Test
      id: Unit-Test-Run
      run: |
        go test

    - name: Build & push Docker image
      id: Build-and-Push-Docker-Image
      uses: mr-smithers-excellent/docker-build-push@v5
      with:
        image: gsdockit/goapiauth
        tags: latest
        registry: docker.io
        dockerfile: Dockerfile
        username: ${{ secrets.DOCKER_USERNAME }}
        password: ${{ secrets.DOCKER_PASSWORD }}

    - name: Posting Action Workflow updates to Slack
      uses: act10ns/slack@v1
      with: 
        status: ${{ job.status }}
        steps: ${{ toJson(steps) }}
        channel: '#github-updates'
      if: always()
    env:
      SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}

• The full source code can be accessible in this GitHub repo

GitHub Action Workflow Run Output

• Here is how it runs the workflow and it can be viewable from the Actions tab

Additional Info

Developer - Saravanan G (chefgs)

Other details that might be helpful to users starting to write GitHub Actions

How to Add GitHub Actions workflow

• Our workflow gets created in .github/workflows as an .yaml file

Method 1:

• Step 1: We can find Actions tab on the repo
• Step 2: Click on the tab and choose New Workflow
• Step 3: Choose workflow from the pre-defined template
• Step 4: Edit the workflow yaml according to the required stages

or

Method 2:

• Create workflow for yourself from scratch using the documentation guide

Enjoy creating the GitHub Workflow

How to Integrate Slack with GitHub Actions Workflow

Here is the list of steps to integrate slack with github actions,

• Add github app to the slack channel
• Add incoming webhook app and pick webhook url and keep it
• Run the below command in slack channel to subscribe to repo updates. (while adding, it asks for auth with github and we choose repo)

/github subscribe user/repo

• Add incoming webhook URL as secret in the specific repo we want to get updates
• Add the below code at the end of Action workflow to get the job updates in slack

  - name: Posting Action Workflow updates to Slack
      uses: act10ns/slack@v1
      with: 
        status: ${{ job.status }}
        steps: ${{ toJson(steps) }}
        channel: '#github-actions-updates'
      if: always()
    env:
      SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}

• Each steps in workflow should have id: step-name to get the status of the step in Slack update

Now let's see the details about the code and it's functionality...

Go Source Code Details

Code Objective

• We will be creating a REST API that listens on localhost port 1357 and has the API versioning with a query string parameter.
• Sample URL format we are planning to create, http://localhost:1357/api/v1/PersonId/Id456

Function main

Add the below code function main()

Adding API Versioning and Basic authentication

  // Define gin router
  router := gin.Default()

  // Create Sub Router for customized API version and basic auth
  subRouterAuthenticated := router.Group("/api/v1/PersonId", gin.BasicAuth(gin.Accounts{
    "basic_auth_user": "userpass",
  }))

Passing Query String Parameters

  subRouterAuthenticated.GET("/:IdValue", GetMethod)

REST API Listening on Port

  listenPort := "1357"
  // Listen and Server on the LocalHost:Port
  router.Run(":"+listenPort)

Get Method

• Define a GetMethod function and add the following code
• It fetches and prints the Person IdValue from the query string parameter passed in the API URL

func GetMethod(c *gin.Context) {
  fmt.Println("\n'GetMethod' called")
  IdValue := c.Params.ByName("IdValue")
  message := "GetMethod Called With Param: " + IdValue
  c.JSON(http.StatusOK, message)

  // Print the Request Payload in console
  ReqPayload := make([]byte, 1024)
  ReqPayload, err := c.GetRawData()
  if err != nil {
        fmt.Println(err)
        return
  }
  fmt.Println("Request Payload Data: ", string(ReqPayload))
}

Go REST API Unit testing

• Go testing module can be used for creating unit testing code for Go source
• Go testing module code has been found in api_authtest.go
• Run the command go test to run the tests