Jenkins - How to access BUILD_NUMBER environment variable

Question

Are Jenkins parameters case-sensitive? I have a parametrized build which needs an ant parameter named "build_parameter" to be set before the build. When I try to access the ${BUILD_NUMBER} set by Jenkins, I get the value set for the ant parameter. If the build parameters are not case sensitive, can anyone suggest me a work around to this issue? I cannot change the build parameter name as I will have to change my build scripts (which is not an option). Thanks!

Answer 1

To Answer your first question, Jenkins variables are case sensitive. However, if you are writing a windows batch script, they are case insensitive, because Windows doesn't care about the case.

Since you are not very clear about your setup, let's make the assumption that you are using an ant build step to fire up your ant task. Have a look at the Jenkins documentation (same page that Adarsh gave you, but different chapter) for an example on how to make Jenkins variables available to your ant task.

EDIT:

Hence, I will need to access the environmental variable ${BUILD_NUMBER} to construct the URL.

Why don't you use $BUILD_URL then? Isn't it available in the extended email plugin?

Answer 2

Assuming I am understanding your question and setup correctly,

If you're trying to use the build number in your script, you have two options:

1) When calling ant, use: ant -Dbuild_parameter=${BUILD_NUMBER}

2) Change your script so that:

<property environment="env" /> <property name="build_parameter"  value="${env.BUILD_NUMBER}"/>