Jenkins pipeline store SSH credentials as parameter - jenkins

Question

I have the following pipeline code:
pipeline {
agent any
environment {
SSH_KEY_PARAMETER = credentials('SSH_KEY')
}
stages {
stage('Checkout') {
steps{
script{
git credentialsId: 'SSH_KEY_PARAMETER', url: 'git#github.com:SomeUser/PrivateRepo.git', branch: 'main'
}
}
}
}
}
Expected output is cloning the repo.
Actual output:
ERROR: Error fetching remote repo 'origin'
hudson.plugins.git.GitException: Failed to fetch from git#github.com:SomeUser/PrivateRepo.git
at hudson.plugins.git.GitSCM.fetchFrom(GitSCM.java:1001)
at hudson.plugins.git.GitSCM.retrieveChanges(GitSCM.java:1242)
at hudson.plugins.git.GitSCM.checkout(GitSCM.java:1302)
at org.jenkinsci.plugins.workflow.steps.scm.SCMStep.checkout(SCMStep.java:129)
at org.jenkinsci.plugins.workflow.steps.scm.SCMStep$StepExecutionImpl.run(SCMStep.java:97)
at org.jenkinsci.plugins.workflow.steps.scm.SCMStep$StepExecutionImpl.run(SCMStep.java:84)
at org.jenkinsci.plugins.workflow.steps.SynchronousNonBlockingStepExecution.lambda$start$0(SynchronousNonBlockingStepExecution.java:47)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: hudson.plugins.git.GitException: Command "git fetch --tags --force --progress -- git#github.com:SomeUser/PrivateRepo.git +refs/heads/*:refs/remotes/origin/*" returned status code 128:
stdout:
stderr: git#github.com: Permission denied (publickey).
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandIn(CliGitAPIImpl.java:2681)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandWithCredentials(CliGitAPIImpl.java:2102)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.access$500(CliGitAPIImpl.java:86)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl$1.execute(CliGitAPIImpl.java:624)
at hudson.plugins.git.GitSCM.fetchFrom(GitSCM.java:999)
If I change the pipeline code to use the credential ID instead of the variable it works:
pipeline {
agent any
environment {
SSH_KEY_PARAMETER = credentials('SSH_KEY')
}
stages {
stage('Checkout') {
steps{
script{
git credentialsId: 'SSH_KEY', url: 'git#github.com:SomeUser/PrivateRepo.git', branch: 'main'
}
}
}
}
}
In my pipeline I need to manage a bunch of SSH keys depending on the environment, so I need to be able to parameterize the SSH key, am I missing something here or is it not possible to assign an SSH key as variable?

Answer 1

Your environment directive with use of the credentials helper method is syntactically correct. Your syntax for accessing the variable is incorrect. You are assigning a literal string value 'SSH_KEY_PARAMETER' to the credentialsId argument. The actual value also is stored in the env object, so you would access it with the appropriate key env.SSH_KEY_PARAMETER. The usage would then look like:
credentialsId: env.SSH_KEY_PARAMETER
However, the git step is expecting the credentials ID for that argument and not the actual credentials. Therefore, you need to also assign the value of the credentialsId in the environment directive instead:
SSH_KEY_PARAMETER = 'SSH_KEY'
Putting it all together, we have:
environment {
SSH_KEY_PARAMETER = 'SSH_KEY'
}
stages {
...
git credentialsId: env.SSH_KEY_PARAMETER, url: 'git#github.com:SomeUser/PrivateRepo.git', branch: 'main'
}