Library directory structure in Jenkins - Step-by-Step Execution

Process Flow - Library directory structure

Start: Jenkins Pipeline

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Load Shared Library

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Look for vars/ directory

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Look for src/ directory

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Look for resources/ directory

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Use library classes and vars in pipeline

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Pipeline executes with shared code

Jenkins pipeline loads the shared library, then looks for specific directories (vars, src, resources) to find reusable code and resources for the pipeline execution.

Execution Sample

Jenkins

library('my-shared-lib')

pipeline {
  agent any
  stages {
    stage('Example') {
      steps { script { myFunction() } }
    }
  }
}

This Jenkins pipeline loads a shared library and calls a function defined in the library's vars directory.

Process Table

Step	Action	Directory Checked	Result	Pipeline Effect
1	Load shared library 'my-shared-lib'	N/A	Library loaded	Library code available
2	Check for vars/ directory	vars/	Found	Functions and vars available for pipeline
3	Check for src/ directory	src/	Found	Classes available for pipeline
4	Check for resources/ directory	resources/	Found	Static files available for pipeline
5	Call myFunction() from vars/	vars/myFunction.groovy	Executed	Step runs in pipeline
6	Pipeline completes	N/A	Success	Pipeline finished
7	Exit	N/A	No more steps	Pipeline ends

💡 Pipeline ends after all stages complete successfully

Status Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	After Step 4	After Step 5	Final
libraryLoaded	false	true	true	true	true	true	true
varsDirFound	false	false	true	true	true	true	true
srcDirFound	false	false	false	true	true	true	true
resourcesDirFound	false	false	false	false	true	true	true
myFunctionCalled	false	false	false	false	false	true	true
pipelineStatus	not started	running	running	running	running	running	success

Key Moments - 2 Insights

Why does Jenkins check multiple directories like vars/, src/, and resources/ in the library?

Jenkins looks in these directories to find different types of reusable code and files: vars/ for simple functions, src/ for classes, and resources/ for static files. This is shown in steps 2, 3, and 4 of the execution table.

What happens if the vars/ directory is missing in the shared library?

If vars/ is missing, functions like myFunction() won't be found, causing pipeline errors when called. Step 2 in the execution table shows vars/ found; if missing, the pipeline would fail at step 5.

Visual Quiz - 3 Questions

Look at the execution table, at which step is the shared library first confirmed loaded?

A Step 2

B Step 5

C Step 1

D Step 7

💡 Hint

Check the 'Action' and 'Result' columns in the first row of the execution table.

According to the variable tracker, when does the variable 'myFunctionCalled' change to true?

A After Step 5

B After Step 4

C After Step 2

D After Step 7

💡 Hint

Look at the 'myFunctionCalled' row and see when it changes from false to true.

If the resources/ directory was missing, which step in the execution table would show a different result?

A Step 3

B Step 4

C Step 2

D Step 5

💡 Hint

Check the 'Directory Checked' and 'Result' columns for step 4.

Concept Snapshot

Jenkins shared libraries have a standard directory structure:
- vars/: simple Groovy scripts as functions
- src/: Groovy classes in packages
- resources/: static files like templates
Pipeline loads the library, then looks in these directories to find reusable code.
Functions in vars/ can be called directly in pipelines.
Classes in src/ require import or usage via @Library.

Full Transcript

This visual execution shows how Jenkins loads a shared library and checks its directory structure. First, the pipeline loads the library, confirming it is available. Then Jenkins looks for the vars/ directory to find simple functions, the src/ directory for classes, and the resources/ directory for static files. Each directory found makes its contents available to the pipeline. The pipeline then calls a function from vars/, which executes successfully. Variables track the state of loading and function calls. Key moments clarify why Jenkins checks multiple directories and what happens if one is missing. The quiz tests understanding of when the library is loaded, when functions are called, and the effect of missing directories.