radish

Radish is a task runner that understands version control.

You define a command that applies to multiple subprojects in your repository and thenradish will figure out which projects have changed and run the command for just those projects. Radish isn't a replacement for make, gulp, gradle, rake, or any other task runner. It's a supplement for orchestrating other runners and scripts with some smarts from your version control repository.

If you're using a CI/CD server like Concourse or GoCD which supports pipelines as first-class citizens you probably have no need for radish on your CI/CD server. It might still be useful on your dev machine, though.

Installation

Radish is available on PyPi as radish-run and can be installed on most systems with pip:

$ pip install radish-run

How to use

An example invocation of radish:

$ radish command tests --from 19abc023 --to 2514ecb1
Changed paths:
  - extensions/cool-extension/
  - frontend/js/

Running tests for extensions/cool-extension/:
...........
OK

Running tests for frontend/js/:
..........................
OK

extensions/cool-extension/: Success (5.13 seconds)
frontend/js/: Success (4.75 seconds)

Finished in 9.88 seconds

Configuration

radish configuration is a yaml file named Radishfile, because I can.

paths:
  - extensions/*/  # Mark each subdirectory in extensions as a path
  - frontend/js/
  
commands:  # Runs from the directory denoted by paths above
  tests:
    default: bin/rspec spec
    frontend/js/: npm test

Parallelization

Radish supports running your commands in parallel by passing in the jobs flag and specifying how many parallel jobs you want to run. This will then run this many projects at the same time. There's also support for parallelization where the running is maintained by something else, where radish splits up the work load and runs each node as a process of its own. This is how for instance CircleCI manages parallelization.

Example invocation on CircleCI:

$ radish command tests --jobs=2 --job=1
Running command tests in parallel as job 2/2

Changed paths:
  - frontend/js/

Running tests for frontend/js/:
..........................
OK

frontend/js/: Success (4.75 seconds)

Finished in 4.75 seconds.

Example of running in parallel:

$ radish command tests --jobs=2
Running command tests in parallel with 2 processes

Changed paths:
  - app/
  - frontend/js/

Running tests for app/:
.......
OK

Running tests for frontend/js/:
..........................
OK

app/: Success (1.35 seconds)
frontend/js/: Success (4.75 seconds)

Cumulative run time: 6.05 seconds.
Finished in 4.81 seconds.

An example use case

Take that you're building a single page web app, it consists of two parts:

• The backend that delivers JSON
• The frontend that holds all the clicky bits that end-users see

Because cross-functional teams this project is in one repository, which is a great win for productivity. But it has a downside: when there are only changes to the backend, then all the tests for the frontend is still run. Finally, after running all tests it can get deployed, but then both sites get deployed despite nothing changing on the frontend.

So this is a crazy situation. It shouldn't be. So this is where radish comes in. You tell radish about test and deploy, and what that means for both the backend and the frontend, then on your CI server you run the commands with the last green commit. Radish then figures out what has changed from the current commit and the last one, and only runs the command for those projects.

Contributing

Roadmap

• Define a path/project to always run, no matter whether there are changes or not
  • Run a different command if there are changes to the project
• Allow for changed files to be passed in to commands. Primarily a feature for local dev boxes, so you only run the command against changed files.
• Dependencies between projects. If the frontend-payment project changes then run the command in the frontend project as well.
• Custom differs for Ci systems so they can smartly figure out what the last green commit was, instead of relying on HEAD~1 as the poor mans "what was the last change?"

Local development

To get started make with your current global version of Python do:

$ git clone https://github.com/gaqzi/radish.git
$ cd radish/
$ make develop
$ make test

This will install all dependencies, check out the test repo, and then run all the tests.

License

Beerware License