Connecting GitHub and Jenkins

💡 What You’ll Need Before You Start

1. A GitHub repo with something Jenkins can build.
2. Jenkins up and running (local or hosted).
3. Git plugin + GitHub plugin installed in Jenkins.
4. GitHub Personal Access Token (PAT) or SSH key for auth.
5. Optionally: Webhook setup so Jenkins gets notified on code pushes (CI magic!).

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🔌 Step 1: Install Git & GitHub Plugins in Jenkins

Head to:

• Manage Jenkins → Manage Plugins → Available
• Search and install:
  • Git Plugin
  • GitHub Plugin
  • (Optional but useful) GitHub Branch Source Plugin
• Restart Jenkins if it asks nicely

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🔐 Step 2: Create GitHub Credentials for Jenkins

You have two good options here:

Option 1: Use HTTPS + PAT (Recommended)

1. Go to GitHub → Settings → Developer settings → Personal Access Tokens
2. Generate a token with:
   • repo access
   • admin:repo_hook (if you want Jenkins to manage webhooks)

Option 2: Use SSH Key (Only if you’re anti-PAT)

1. Generate an SSH key on your Jenkins server: bashCopyEditssh-keygen -t rsa -b 4096 -C "jenkins@yourdomain.com"
2. Add the public key to your GitHub repo under Deploy Keys
3. Add the private key to Jenkins:
   • Manage Jenkins → Credentials → Add a new SSH Username with private key

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⚙️ Step 3: Set Up Your Jenkins Job to Use GitHub

1. Create a new job → Select Pipeline or Freestyle
2. In the Source Code Management section:
   • Select Git
   • Paste your repo URL (https://github.com/username/repo.git)
   • Add your credentials from earlier
3. (Optional but very cool): If using a Jenkinsfile, select “Pipeline script from SCM” and point to your Jenkinsfile in the repo.

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📣 Step 4: Enable GitHub Webhooks (Push-Triggered Builds)

So Jenkins doesn’t sit there twiddling its thumbs.

Option 1: Auto-Webhooks via GitHub Plugin (if you gave Jenkins PAT with admin access)

• Check GitHub hook trigger for GITScm polling in your job’s build triggers

Option 2: Manual Webhook (if you’re DIY-ing it)

1. Go to your GitHub repo → Settings → Webhooks → Add webhook
2. Payload URL: perlCopyEdithttp://<jenkins-server>/github-webhook/ or if Jenkins is running locally and GitHub can’t reach it, use ngrok or a reverse proxy.
3. Content type: application/json
4. Events: Choose Just the push event
5. Save it

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🧪 Step 5: Test It!

1. Commit and push something to your GitHub repo.
2. Jenkins should automatically detect the change and kick off a build.
3. If not:
   • Check webhook delivery logs on GitHub
   • Make sure your Jenkins server is publicly accessible
   • Check job logs for auth errors

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🧠 Bonus: Use Multibranch Pipelines

If you’re working with multiple branches, check out Multibranch Pipeline Jobs:

• They auto-detect branches with a Jenkinsfile
• Jenkins creates separate jobs for each branch
• Supports PR builds too

Set it up under New Item → Multibranch Pipeline

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🔚 Wrap-Up

Now GitHub and Jenkins are linked like Batman and Robin, you’ve unlocked:

• Auto builds on every push
• Super clean CI/CD pipeline tied to your actual code
• Version-controlled Jenkinsfile workflows

No more manual triggers. No more stale builds. Just sweet, sweet automation.