问题
I have installed Jenkins plugins in two ways i.e. manually keeping the .hpi file in Jenkins home directory, and installing from Jenkins front-end (Manage Jenkins > Manage Plugins).
What I notice here is when I install the plugin manually (downloaded as .hpi file) it installed with extension .hpi and while installing the plugin through Jenkins front-end I notice that plugin again installed as .jpi.
But why? What is going on in the background? I know functionality won't change but it looks interesting to know.
回答1:
Both are supposed to be identical to that extend that Jenkins is renaming hpi to jpi when you install it manually as you said.
The reason why you see both in your JENKINS_HOME is the order in which plugins are loaded when Jenkins boots up: plugin.jpi gets precedence over plugin.hpi in case both are present. This is the way the upload installation makes sure the uploaded version will override the existing one after the restart.
回答2:
Well I think its because Jenkins forked from Hudson so that is the 'H' in hpi. The J is obviously a change to that.
In terms of technology, the jpi plugins are generated using the gradle plugin architecture and hpi plugins are generated with the Maven architecture
Ultimately, as you have found both produce plugins which Jenkins can use. The vast majority are built using Maven but I am a fan of Gradle as it links nicely in with developing plugins in Groovy. You can also build in Groovy using Maven
回答3:
Plugins as present in $JENKINS_HOME/plugins/ should always be using the .jpi suffix (with the basename being the plugin identifier). Normally Jenkins will enforce this naming pattern even when uploading a plugin manually, regardless of what filename you used for the upload, so I am not sure how you came to have a *.hpi file here, unless you directly copied it into this filesystem location.
来源：https://stackoverflow.com/questions/30658375/what-is-difference-between-hpi-and-jpi-of-jenkins-plugins