Use Jenkins REST API to Update Job Configurations Automatically

I manage several Jenkins jobs for a single git repository that has several modules (i.e. directories). Each of the modules has the same structure and the job for each of the modules is essentially the same, differentiated only by the name of the directory.

I recently needed to make a change to each of the job configurations and rather than do so by hand, I thought I'd investigate the possibility of doing so automatically using the Jenkins REST API.

I had originally created all the jobs using the API by posting to the generic the http://jenkins.example.com/createItem URI. I had since moved the jobs into folders and hitting createItem only created new jobs and did not update the proper jobs.

I did some searching on the internet and couldn't find any help. I eventually found my answer on the api page for the folder. I'm posting my code below for anyone else with similar questions.

# First, get the http://jenkins.example.com/job/folder-name/job/sample-job--template/configure looking like you want

read -s token
# type token from http://jenkins.example.com/user/$userName/configure

# Download the configuration XML for the template job (which will be our model template)
curl -v -u "bvanevery:$token" http://jenkins.example.com/job/folder-name/job/sample-job--template/config.xml > generic-config.xml

# My modules
declare modules=('module1' 'module2' 'module3')

# POST the updated configuration XML to Jenkins
for m in ${modules[@]}; do 
   echo "module $m";
   sed "s/MODULE/$m/g" generic-config.xml > $m-config.xml; 
   curl -v -X POST --data-binary @$m-config.xml -u "bvanevery:$token" \
        -H 'Content-Type: application/xml' \
        "http://jenkins.example.com/job/folder-name/job/$m/config.xml ;
done