Get error reason in Jenkinsfile failure - jenkins

Question

I have the following post failure section:
post {
failure {
mail subject: "\u2639 ${env.JOB_NAME} (${env.BUILD_NUMBER}) has failed",
body: """Build ${env.BUILD_URL} is failing!
|Somebody should do something about that""",
to: "devel#example.com",
replyTo: "devel#example.com",
from: 'jenkins#example.com'
}
}
I would like to include the reasons why the build failed in the body of the error message.
How can I do that?
If not, is there a way to attach the build log file to the email?

Answer 1

I don't know of a way to retrieve the failure reason automatically out of thin air.
However, you can use "post{ failure {" blocks in each phase to capture at least the phase in which it failed into a environment variable (e.g. env.FAILURE_REASON), and access that env var in the final (global scope) notification block.
For more granularity, you can reuse the same mechanism of the global env variable, but use try { } catch { } blocks to capture which specific step failed.
A generic example would be:
pipeline {
stages {
stage('Build') {
steps {
...
}
post {
failure {
script { env.FAILURE_STAGE = 'Build' }
}
}
}
stage('Deploy') {
steps {
...
}
post {
failure {
script { env.FAILURE_STAGE = 'Deploy' }
}
}
}
...
}
post {
failure {
mail subject: "\u2639 ${env.JOB_NAME} (${env.BUILD_NUMBER}) has failed",
body: """Build ${env.BUILD_URL} is failing in ${env.FAILURE_STAGE} stage!
|Somebody should do something about that""",
to: "devel#example.com",
replyTo: "devel#example.com",
from: 'jenkins#example.com'
}
}
}
Technically, you can even do some automated triage based on the failing stage and send a more targeted notification, or even create specific (e.g. Jira) tickets.
For attaching the console log to the email notification, you'd want to look at
emailext and the 'attachLog: true' attribute