Shared Library and @Field - not global

Using Jenkins
1

I had to replace an groovy.transform.Field variable in the /vars script with a singleton in the /src directory. What I found is that OTHER scripts in /vars got their own instance. So, the log() script had a Level variable … INFO, DEBUG, TRACE, etc. and in the main Jenkinsfile/script would set the level to DEBUG, but scripts would have the initial value. Is this what - Internally, scripts in the vars directory are instantiated on-demand as singletons - means.

2

I’m sorry I don’t have any idea what your asking if anything. Its kinda just a statement.

I’ve only used shared libraries where var/ is functions (ex buildHelpChart()). I haven’t used src/ yet, but it looks like based on Extending with Shared Libraries things in src/ are classes you can import and use as classes.

What log() script are you talking about? What level? do you have your snippet public at all describing your problem?

3

thanks for that feedback. Let me re-phrase as a question. I have two scripts in /vars, and the main script/Jenkins file.

// vars/log.groovy:
@groovy.transform.Field
int logLevel = INFO // say that's 0

setLevel( int level ) { logLevel = level }

call( int level, String message ) {
  if (level <= logLevel) { echo "${message}" }

// vars/foo.groovy
call() { log( DEBUG, "hello world.") }

// Jenkinsfile
log.setLevel(DEBUG) // say debug is 1
foo()

Question: why does foo() never echo “hello world” ? When I call setLevel(DEBUG) in the Jenkinsfile, why is it still “INFO” within log() ?

4

A few things,

1 - @Field decorator makes a variable an instance field , which is automatically not “global” in static variable sense. Without @Field, the variable would be a script local, with it it is an instance field.

2 - Jenkins does weird thing with items in /vars - I think it lazy-loads them on demand for you and tries to reuse them, but it appears that Jenkinsfile vs code in vars a seem to get a different instance. I would not count on the instances being the same.

3 - To achieve what you are trying to achieve you need to either a - pass context, or b - use a true static. Not sure if scripts support statics - need to look it up, but you can simply create a new class (in /src, or as an inner class inside log.groovy and set a static variable to store log level.

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