Jenkins "Console Output" log location in filesystem - jenkins

Question

I want to access and grep Jenkins Console Output as a post build step in the same job that creates this output. Redirecting logs with >> log.txt is not a solution since this is not supported by my build steps.
Build:
echo "This is log"
Post build step:
grep "is" path/to/console_output
Where is the specific log file created in filesystem?

Answer 1

#Bruno Lavit has a great answer, but if you want you can just access the log and download it as txt file to your workspace from the job's URL:
${BUILD_URL}/consoleText
Then it's only a matter of downloading this page to your ${Workspace}
You can use "Invoke ANT" and use the GET target
On Linux you can use wget to download it to your workspace
etc.
Good luck!
Edit:
The actual log file on the file system is not on the slave, but kept in the Master machine. You can find it under: $JENKINS_HOME/jobs/$JOB_NAME/builds/lastSuccessfulBuild/log
If you're looking for another build just replace lastSuccessfulBuild with the build you're looking for.

Answer 2

Jenkins stores the console log on master. If you want programmatic access to the log, and you are running on master, you can access the log that Jenkins already has, without copying it to the artifacts or having to GET the http job URL.
From http://javadoc.jenkins.io/archive/jenkins-1.651/hudson/model/Run.html#getLogFile(), this returns the File object for the console output (in the jenkins file system, this is the "log" file in the build output directory).
In my case, we use a chained (child) job to do parsing and analysis on a parent job's build.
When using a groovy script run in Jenkins, you get an object named "build" for the run. We use this to get the http://javadoc.jenkins.io/archive/jenkins-1.651/hudson/model/Build.html for the upstream job, then call this job's .getLogFile().
Added bonus; since it's just a File object, we call .getParent() to get the folder where Jenkins stores build collateral (like test xmls, environment variables, and other things that may not be explicitly exposed through the artifacts) which we can also parse.
Double added bonus; we also use matrix jobs. This sometimes makes inferring the file path on the system a pain. .getLogFile().getParent() takes away all the pain.

Answer 3

You can install this Jenkins Console log plugin to write the log in your workspace as a post build step.
You have to build the plugin yourself and install the plugin manually.
Next, you can add a post build step like that:
With an additional post build step (shell script), you will be able to grep your log.
I hope it helped :)

Answer 4

Log location:
${JENKINS_HOME}/jobs/${JOB_NAME}/builds/${BUILD_NUMBER}/log
Get log as a text and save to workspace:
cat ${JENKINS_HOME}/jobs/${JOB_NAME}/builds/${BUILD_NUMBER}/log >> log.txt

Answer 5

For very large output logs it could be difficult to open (network delay, scrolling). This is the solution I'm using to check big log files:
https://${URL}/jenkins/job/${jobName}/${buildNumber}/
in the left column you see: View as plain text. Do a right mouse click on it and choose save links as. Now you can save your big log as .txt file. Open it with notepad++ and you can go through your logs easily without network delays during scrolling.

Answer 6

I found the console output of my job in the browser at the following location:
http://[Jenkins URL]/job/[Job Name]/default/[Build Number]/console

Answer 7

This is designed for use when you have a shell script build step. Use only the first two lines to get the file name.
You can get the console log file (using bash magic) for the current build from a shell script this way and check it for some error string, failing the job if found:
logFilename=${JENKINS_HOME}/${JOB_URL:${#JENKINS_URL}}
logFilename=${logFilename//job\//jobs\/}builds/${BUILD_NUMBER}/log
grep "**Failure**" ${logFilename} ; exitCode=$?
[[ $exitCode -ne 1 ]] && exit 1
You have to build the file name by taking the JOB_URL, stripping off the leading host name part, adding in the path to JENKINS_HOME, replacing "/job/" to "/jobs/" to handle all nested folders, adding the current build number and the file name.
The grep returns 0 if the string is found and 2 if there is a file error. So a 1 means it found the error indication string. That makes the build fail.

Answer 8

Easy solution would be:
curl http://jenkinsUrl/job/<Build_Name>/<Build_Number>/consoleText -OutFile <FilePathToLocalDisk>
or for the last successful build...
curl http://jenkinsUrl/job/<Build_Name>/lastSuccessfulBuild/consoleText -OutFile <FilePathToLocalDisk>