Chain: A Flexible Action-Workflow Library

The chain package provides a flexible framework for building and executing sequential workflows of actions. It allows you to define a series of steps, each represented by an Action, which processes inputs and produces outputs. The package supports conditional branching, customizable execution paths, and error handling, enabling complex workflows with minimal boilerplate.

Features

• Action and Workflow Composition
  Create modular, reusable units of work (Action) and orchestrate them into robust workflows using Workflow.

• DAG-based Execution Plans
  Ensure predictable execution and robust validation with built-in cycle detection to enforce acyclic workflows.

• Nested Workflows
  Use Workflows as actions within other Workflows, enabling modular and hierarchical workflow designs.

• Conditional Branching
  Support for Success, Failure, Abort and custom direction-based branching within your execution flows.

• AggregateAction Support
  Simplify the orchestration of complex workflows by combining Actions or Workflows of different types into a unified control flow using AggregateAction.

Getting Started

Installation

To install the chain package, use the following command:

go get github.com/JSYoo5B/chain

Key Concepts

Action

An Action represents a single task in the Workflow. Each action can process input data and return output or an error.

type Action[T any] interface {
    Name() string
    Run(ctx context.Context, input T) (output T, err error)
}

BranchAction

A BranchAction extends Action and supports conditional branching. It can change the execution flow based on the results of the action, allowing for multiple execution paths.

type BranchAction[T any] interface {
    Name() string
    Run(ctx context.Context, input T) (output T, err error)
    Directions() []string
    NextDirection(ctx context.Context, output T) (direction string, err error)
}

Workflow

A Workflow is a sequence of Actions executed in order. It orchestrates the flow of data between actions and handles branching, success, error, and abort conditions.

ActionPlan

An ActionPlan is a map that associates a direction (e.g., success, error, abort) with the next Action to execute, defining the flow of a Workflow.

type ActionPlan[T any] map[string]Action[T]

Examples

Practical examples for using the chain package will be added in future updates. Stay tuned!