Crate captain_workflow_manager

This library helps you run pipelines of jobs that depend on each other. Its modularity allows to run jobs either locally, on a cluster or other remote computing resources.

Consider a set of jobs as illustrated below, where two kind of source files are used to generate two kind of intermediate files which are in turn used to generate a final result.

                         ┌─────────────────┐
┌─────────────────┐      │  Source File B: │
│  Source File A: │      │    - Param1     │
│    - Param1     │      │    - Param2     │
└─────────┬───────┘      └───────┬─────────┘
          │                      │
          │                      │
          │           ┌──────────┴───────────────┐
          │           │                          │
          │           │                          │
          │           │                          │
          ▼           ▼                          ▼
      ┌──────────────────────┐       ┌──────────────────────┐
      │ Intermediate File A: │       │ Intermediate File B: │
      │   - Param1           │       │   - Param1           │
      │   - Param2           │       │   - Param2           │
      └────────────────┬─────┘       └──────┬───────────────┘
                       │                    │
                       └─────────┬──────────┘
                                 │
                                 │
                                 ▼
                         ┌───────────────┐
                         │ Final Result: │
                         │   - Param1    │
                         │   - Param2    │
                         └───────────────┘

Each kind of file has one or more “parameters”.

This dependency could be represented by the following Job enum, assuming that Param1 is an integer and Param2 a string:

enum Job {
    SourceFileA {param1: u16},
    SourceFileB {param1: u16, param2: &'static str},
    IntermediateFileA {param1: u16, param2: &'static str},
    IntermediateFileB {param1: u16, param2: &'static str},
    FinalResult {param1: u16, param2: &'static str},
}

To manage this set of jobs using captain, one would first implement the JobUnit trait on it. And then run it using the job Scheduler. The back-end to run it on is chosen by selecting an ExecutorBuilder.

Modules

• executor
  Module containing the traits needed to be a job executor as well as provided job executors

Structs

• Scheduler
  The entry point of the crate, implementing the job scheduling logic
• ToRun
  A job to be run by an Executor

Enums

• Error
  The Error type of this crate

Traits

• JobUnit
  A trait that must be implemented by struct representing job units.