Email notification plugin in Jenkins - Step-by-Step Execution

Process Flow - Email notification plugin

Job starts

↓

Build runs

↓

Build finishes

↓

Check build result

↓

Send email

↓

End

The Jenkins job runs a build, then depending on success or failure, it triggers the email notification plugin to send an email.

Execution Sample

Jenkins

pipeline {
  agent any
  stages {
    stage('Build') {
      steps { echo 'Building...' }
    }
  }
  post {
    success { mail to: '[e-mail]', subject: 'Build Success', body: 'Good job!' }
    failure { mail to: '[e-mail]', subject: 'Build Failed', body: 'Please check.' }
  }
}

This Jenkins pipeline sends an email after the build stage depending on success or failure.

Process Table

Step	Build Status	Condition Checked	Email Sent	Email Subject
1	Running	N/A	No	N/A
2	Success	Success?	Yes	Build Success
3	Success	Failure?	No	N/A
4	End	N/A	N/A	N/A

💡 Build finished with success, email sent with subject 'Build Success'.

Status Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	Final
buildStatus	N/A	Running	Success	Success	Success
emailSent	No	No	Yes	Yes	Yes
emailSubject	N/A	N/A	Build Success	Build Success	Build Success

Key Moments - 2 Insights

Why is the email sent only after the build finishes and not during the build?

The execution_table shows that email is sent only after the buildStatus changes to Success or Failure (Step 2), ensuring notifications reflect final build results.

What happens if the build fails? Does the success email get sent?

According to the execution_table, if the build fails, the failure condition triggers email sending, and the success email is not sent (Step 3 shows no success email sent).

Visual Quiz - 3 Questions

Look at the execution_table, at which step is the email with subject 'Build Success' sent?

A Step 3

B Step 1

C Step 2

D Step 4

💡 Hint

Check the 'Email Sent' and 'Email Subject' columns in execution_table rows.

According to variable_tracker, what is the value of 'buildStatus' after Step 1?

A Running

B Failure

C Success

D N/A

💡 Hint

Look at the 'buildStatus' row under 'After Step 1' in variable_tracker.

If the build failed, which email subject would be sent according to the plugin logic?

A Build Success

B Build Failed

C Build Running

D No email sent

💡 Hint

Refer to the concept_flow and execution_table showing email subjects for failure.

Concept Snapshot

Jenkins Email Notification Plugin:
- Sends emails after build completion.
- Use 'post' block in pipeline for success/failure.
- 'mail' step sends email with to, subject, body.
- Emails reflect final build status only.
- Helps team stay informed automatically.

Full Transcript

In Jenkins, the Email Notification Plugin sends emails after a build finishes. The pipeline runs the build stage, then checks if the build succeeded or failed. Depending on the result, it sends an email with a subject like 'Build Success' or 'Build Failed'. The execution table shows the build status changing from running to success, triggering the email. Variables track the build status and email details step by step. This ensures notifications only go out after the build is complete, keeping the team updated on results.

Practice

1. What is the main purpose of the Jenkins Email Notification plugin?

easy

A. To deploy applications to servers

B. To automatically send emails about build status

C. To monitor server CPU usage

D. To create new Jenkins jobs

Solution

1. Step 1: Understand the plugin's function

   The Email Notification plugin is designed to send emails automatically when a build finishes.

2. Step 2: Identify the correct purpose

   It helps keep the team informed by sending build status emails without manual effort.

3. Final Answer:

   To automatically send emails about build status -> Option B

4. Quick Check:

   Email Notification plugin = automatic build emails [OK]

Hint: Email plugin = auto send build status emails [OK]

Common Mistakes:

• Confusing with deployment tools
• Thinking it monitors server health
• Assuming it creates jobs

2. Which of the following is the correct syntax to enable email notifications in a Jenkins pipeline script?

easy

A. sendEmail(subject: 'Build Status', body: 'Build completed', to: '[e-mail]')

B. emailNotify(subject: 'Build Status', body: 'Build completed', to: '[e-mail]')

C. emailext(subject: 'Build Status', body: 'Build completed', to: '[e-mail]')

D. notifyEmail(subject: 'Build Status', body: 'Build completed', to: '[e-mail]')

Solution

1. Step 1: Recall Jenkins pipeline email syntax

   The Email Extension plugin uses the emailext step to send emails.

2. Step 2: Match the correct function name and parameters

   Only emailext(subject: 'Build Status', body: 'Build completed', to: '[e-mail]') uses emailext with correct parameters: subject, body, and to.

3. Final Answer:

   emailext(subject: 'Build Status', body: 'Build completed', to: '[e-mail]') -> Option C

4. Quick Check:

   Use emailext for email notifications [OK]

Hint: Use 'emailext' step for Jenkins email notifications [OK]

Common Mistakes:

• Using incorrect function names
• Missing required parameters
• Confusing with other plugins

3. Given this Jenkins pipeline snippet:

pipeline {
  agent any
  stages {
    stage('Build') {
      steps {
        echo 'Building...'
      }
    }
  }
  post {
    failure {
      emailext(
        subject: 'Build Failed',
        body: 'Please check the build logs.',
        to: '[e-mail]'
      )
    }
  }
}

What happens if the build fails?

medium

A. An email with subject 'Build Failed' is sent to [e-mail]

B. No email is sent because the syntax is wrong

C. An email is sent only if the build succeeds

D. The build will retry automatically

Solution

1. Step 1: Analyze the post-failure block

   The post { failure { ... } } block runs only if the build fails.

2. Step 2: Understand the emailext usage

   The emailext step sends an email with the given subject and body to the specified address.

3. Final Answer:

   An email with subject 'Build Failed' is sent to [e-mail] -> Option A

4. Quick Check:

   Post failure triggers email = An email with subject 'Build Failed' is sent to [e-mail] [OK]

Hint: Post failure block sends email on build failure [OK]

Common Mistakes:

• Thinking email sends on success
• Assuming syntax error without checking
• Confusing retry with email notification

4. You configured the Email Notification plugin but no emails are sent after build failures. Which is the most likely cause?

medium

A. SMTP server settings are missing or incorrect

B. The Jenkins job has no build steps

C. The build always succeeds

D. The plugin is not installed

Solution

1. Step 1: Check email sending prerequisites

   Jenkins needs correct SMTP server settings to send emails.

2. Step 2: Identify common misconfiguration

   If SMTP settings are missing or wrong, emails won't send even if plugin is configured.

3. Final Answer:

   SMTP server settings are missing or incorrect -> Option A

4. Quick Check:

   SMTP config missing = no emails sent [OK]

Hint: Verify SMTP settings to fix email sending issues [OK]

Common Mistakes:

• Ignoring SMTP configuration
• Assuming plugin auto-configures SMTP
• Thinking build steps affect email sending

5. You want to send an email notification only when the build status changes (e.g., from success to failure or failure to success). Which Email Notification plugin feature should you use?

hard

A. Use the 'Send e-mail for every unstable build' option

B. Use the 'Always send e-mail' option

C. Configure a post-build script to check status manually

D. Enable 'Send e-mail only on status change' in the plugin settings

Solution

1. Step 1: Understand the requirement

   The goal is to send emails only when build status changes, not every build.

2. Step 2: Identify plugin feature for status change

   The Email Notification plugin has an option named 'Send e-mail only on status change' to handle this.

3. Step 3: Compare other options

   Options A and D send emails more frequently; Configure a post-build script to check status manually requires manual scripting.

4. Final Answer:

   Enable 'Send e-mail only on status change' in the plugin settings -> Option D

5. Quick Check:

   Status change emails = enable plugin's status change option [OK]

Hint: Enable 'send only on status change' to reduce email noise [OK]

Common Mistakes:

• Choosing options that send emails every build
• Ignoring built-in plugin features
• Overcomplicating with manual scripts