This document serves to provide necessary information and concepts into the pipeline library.
There are two top-level packages:
com.redhat.common: This package contains common things that aren't specific to pipelines. These classes/interfaces are candidates who can live elsewhere.com.redhat.pipeline: This package contains all the pipeline specific code. It does not contain and Red Hat specific functionality.com.redhat.step: This package contains all the step specific code. It does not contain and Red Hat specific functionality.
Where possible, I've tried to use parent packages to contain things like super classes or interfaces. Child package classes then extend or implement those found in the parent packages.
As the name implies, this context is used to store variables. We have three variable types:
- Global variables: shared across all pipelines within a JVM instance.
- Pipeline variables: shared across all steps within an instance of a running pipeline.
- Step variables: variables local and specific to an executing step within a pipeline.
One of the core concepts is the notion of a definition:
- Definition: to add a definition requires a name and its "native" initial form. For example a pipeline uses a string that contains markup for the pipeline, whereas a step is denoted via a class.
- Creating: using the definition's name and the initial state of the definition, we can create an instance.
- The intermediary form of all pipelines is the Java object
org.json.JSONObject. One may question why? This class is generic enough to represent the JSON, XML or YAML markup and is hierarchical in nature.
Interface (in above parent package)
Child package
- Abstract base
- Default impl
- Any impl
Create() calls Populate Populate does the work.
- Need a StepExecutor
- One place to run pipelines: there are two - AbstractPipeline and AbstractPipelineExecutor