How to read log file from within pipeline? - jenkins

Question

I have a pipeline job that runs a maven build. In the "post" section of the pipeline, I want to get the log file so that I can perform some failure analysis on it using some regexes. I have tried the following:
def logContent = Jenkins.getInstance()
.getItemByFullName(JOB_NAME)
.getBuildByNumber(
Integer.parseInt(BUILD_NUMBER))
.logFile.text
Error for the above code
Scripts not permitted to use staticMethod jenkins.model.Jenkins
getInstance
currentBuild.rawBuild.getLogFile()
Error for the above code
Scripts not permitted to use method hudson.model.Run getLogFile
From my research, when I encounter these, I should be able to go to the scriptApproval page and see a prompt to approve these scripts, but when I go to that page, there are no new prompts.
I've also tried loading the script in from a separate file and running it on a different node with no luck.
I'm not sure what else to try at this point, so that's why I'm here. Any help is greatly appreciated.
P.S. I'm aware of the BFA tool, and I've tried manually triggering the analysis early, but in order to do that, I need to be able to access the log file, so I run into the same issue.

Answer 1

You can use pipeline step httpRequest from here
pipeline {
agent any
stages {
stage('Build') {
steps {
echo 'Test fetch build log'
}
post {
always {
script {
def logUrl = env.BUILD_URL + 'consoleText'
def response = httpRequest(
url: logUrl,
authentication: '<credentialsId of jenkins user>',
ignoreSslErrors: true
)
def log = response.content
echo 'Build log: ' + log
}
}
}
}
}
}
If your jenkins job can run on linux machine, you can use curl to archive same goal.
pipeline {
agent any
stages {
stage('Build') {
environment {
JENKINS_AUTH = credentials('< credentialsId of jenkins user')
}
steps {
sh 'pwd'
}
post {
always {
script {
def logUrl = env.BUILD_URL + 'consoleText'
def cmd = 'curl -u ${JENKINS_AUTH} -k ' + logUrl
def log = sh(returnStdout: true, script: cmd).trim()
echo 'Build log: ' +
echo log
}
}
}
}
}
}
Above two approaches both require the credentials is Username and password format. More detail about what is it and how to add in Jenkins, please look at here

Answer 2

Currently this is not possible via the RunWrapper object that is made available. See https://issues.jenkins.io/browse/JENKINS-46376 for a request to add this.
So the only options are:
explicitly whitelisting the methods
read the log via the URL as described in the other answer, but this requires either anonymous read access or using proper credentials.