Pipeline Initialization

flowchart TD
    subgraph External to JTE
    WorkflowRun
    end
    subgraph JTE
    WorkflowRun-->|create|TemplateFlowDefinition
    TemplateFlowDefinition-->PipelineConfigurationAggregator
    TemplateFlowDefinition-->PipelineTemplateResolver
    TemplateFlowDefinition-->TemplatePrimitiveInjector
    end

Often, knowing which file to start with can be the biggest hurdle to understanding a new codebase.

In JTE, the class that kicks everything off is TemplateFlowDefinition.

When a pipeline kicks off, a WorkflowRun is created and eventually the run() method is called. The run() method fetches the job's FlowDefinition and invokes create() to return a FlowExecution.

JTE's TemplateFlowDefinition.create() is where Pipeline Initialization is performed.

Stages of Pipeline Initialization

The steps JTE performs before the pipeline starts is referred to as Pipeline Initialization.

Pipeline Initialization Stage	Description
Aggregate Pipeline Configurations	Fetches the run's Pipeline Configuration files, parses them, and then merges them to create the Aggregated Pipeline Configuration
Determine the Pipeline Template	Reads the Aggregated Pipeline Configuration and fetches the appropriate Pipeline Template
Create the Pipeline Primitives	Parses the Aggregated Pipeline Configuration to create the Pipeline Primitives