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Package io.github.cdklabs.projen

projen

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Package io.github.cdklabs.projen Description

projen

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Define and maintain complex project configuration through code.

JOIN THE #TemplatesAreEvil MOVEMENT!

projen synthesizes project configuration files such as package.json, tsconfig.json, .gitignore, GitHub Workflows, eslint, jest, etc from a well-typed definition written in JavaScript.

Check out this talk about projen.

As opposed to existing templating/scaffolding tools, projen is not a one-off generator. Synthesized files should never be manually edited (in fact, projen enforces that). To modify your project setup, users interact with rich strongly-typed class and execute projen to update their project configuration files.

Getting Started

To create a new project, run the following command and follow the instructions: 

 $ mkdir my-project
 $ cd my-project
 $ git init
 $ npx projen new PROJECT-TYPE
 πŸ€– Synthesizing project...
 ...

Currently supported project types (use npx projen new without a type for a list):

Use npx projen new PROJECT-TYPE --help to view a list of command line switches that allows you to specify most project options during bootstrapping. For example: npx projen new jsii --author-name "Jerry Berry".

The new command will create a .projenrc.js file which looks like this for jsii projects: 

 const { JsiiProject } = require('projen');
 
 const project = new JsiiProject({
   authorAddress: "elad.benisrael@gmail.com",
   authorName: "Elad Ben-Israel",
   name: "foobar",
   repository: "https://github.com/eladn/foobar.git",
 });
 
 project.synth();

This program instantiates the project type with minimal setup, and then calls synth() to synthesize the project files. By default, the new command will also execute this program, which will result in a fully working project.

Once your project is created, you can configure your project by editing .projenrc.js and re-running npx projen to synthesize again.

The files generated by projen are considered an "implementation detail" and projen protects them from being manually edited (most files are marked read-only, and an "anti tamper" check is configured in the CI build workflow to ensure that files are not updated during build).

For example, to setup PyPI publishing in jsii projects, you can use python option: 

 const project = new JsiiProject({
   // ...
   python: {
     distName: "mydist",
     module: "my_module",
   }
 });

Run: 

 npx projen

And you'll notice that your package.json file now contains a python section in it's jsii config and the GitHub release.yml workflow includes a PyPI publishing step.

We recommend to put this in your shell profile, so you can simply run pj every time you update .projenrc.js: 

 alias pj='npx projen'

Most projects come with an assortment of tasks that handle various development activities, from compiling to publishing. Tasks can be and composed together, and can be run as local commands or turned into GitHub workflows. You can list all tasks with npx projen --help: 

 $ npx projen --help
 projen [command]
 
 Commands:
   projen new [PROJECT-TYPE-NAME] [OPTIONS]  Creates a new projen project
   projen clobber                            hard resets to HEAD of origin and cleans the local repo
   projen compile                            Only compile
   projen test:compile                       compiles the test code
   projen test                               Run tests
   projen build                              Full release build (test+compile)
   projen upgrade-dependencies               upgrade dependencies
   projen upgrade-projen                     upgrade projen
 ...

The build task is the same task that's executed in your CI builds. It typically compiles, lints, tests and packages your module for distribution.

Shell Completions

If installed as a global package, projen includes rich shell tab-completion support. To enable this in your shell, run: 

 # Bash
 projen completion >> ~/.bashrc
 
 # ZSH
 projen completion >> ~/.zshrc

Features

Some examples for features built-in to project types:

API Reference

See API Reference for API details.

In addition, several projen components and project types are explained with examples in /docs (currently a work in progress!).

Ecosystem

projen takes a "batteries included" approach and aims to offer dozens of different project types out of the box (we are just getting started). Think projen new react, projen new angular, projen new java-maven, projen new awscdk-typescript, projen new cdk8s-python (nothing in projen is tied to javascript or npm!)...

Adding new project types is as simple as submitting a pull request to this repo and exporting a class that extends projen.Project (or one of it's derivatives). Projen automatically discovers project types so your type will immediately be available in projen new.

Projects in external modules

projen is bundled with many project types out of the box, but it can also work with project types and components defined in external jsii modules (the reason we need jsii is because projen uses the jsii metadata to discover project types & options in projen new).

Say we have a module in npm called projen-vuejs which includes a single project type for vue.js: 

 $ npx projen new --from projen-vuejs

If the referenced module includes multiple project types, the type is required. Switches can also be used to specify initial values based on the project type APIs. You can also use any package syntax supported by yarn add like projen-vuejs@1.2.3, file:/path/to/local/folder, git@github.com/awesome/projen-vuejs#1.2.3, etc. 

 $ npx projen new --from projen-vuejs@^2 vuejs-ts --description "my awesome vue project"

Under the hood, projen new will install the projen-vuejs module from npm (version 2.0.0 and above), discover the project types in it and bootstrap the vuejs-ts project type. It will assign the value "my awesome vue project" to the description field. If you examine your .projenrc.js file, you'll see that projen-vuejs is defined as a dev dependency: 

 const { VueJsProject } = require('projen-vuejs');
 
 const project = new VueJsProject({
   name: 'my-vuejs-sample',
   description: "my awesome vue project",
   // ...
   devDeps: [
     'projen-vuejs'
   ]
 });
 
 project.synth();

Roadmap

See Vision.

FAQ

Do I have to write my configuration in JavaScript?

Not at all! JavaScript is the default, but it's also possible to write it in Java, TypeScript, or even JSON. Python support is also planned. This is made possible by the jsii library which allows us to write APIs once and generate libraries in several languages. You can choose a different language by passing the --projenrc-ts, --projenrc-java, or --projenrc-json flags when running projen new.

Note: using a .projenrc.json file to specify configuration only allows accessing a subset of the entire API - the options which are passed to the constructor of each project type.

Contributions

Contributions of all kinds are welcome! Check out our contributor's guide and our code of conduct.

For a quick start, check out a development environment: 

 $ git clone git@github.com:projen/projen
 $ cd projen
 $ yarn
 $ yarn watch # compile in the background

Thanks goes to these wonderful people (emoji key):


Elad Ben-Israel
πŸ’»
Christopher Rybicki
πŸ’»
Philip M. Gollucci
πŸ’»
Thorsten Hoeger
πŸ’»
Kenneth Winner
πŸ’»
Jordan Sinko
πŸ’»
Josh Kellendonk
πŸ’»

andrestone
πŸ’»
Cristian PallarΓ©s
πŸ’»
Jonathan Goldwasser
πŸ’»
Matthew Bonig
πŸ’»
Pahud Hsieh
πŸ’»
Adam Elmore
πŸ’»
Ash
πŸ’»

Jacob
πŸ’»
Kraig Amador
πŸ’»
Martin Muller
πŸ’»
Tomasz Łakomy
πŸ’»
john-tipper
πŸ’»
Henry Sachs
πŸ’»
Joseph Egan
πŸ’»

Sebastian Korfmann
πŸ’»
Bart Callant
πŸ’»
Campion Fellin
πŸ’»
Grady Barrett
πŸ’»
Hassan Mahmud
πŸ’»
Hassan Mahmud
πŸ’»
Jake Pearson
πŸ’»

Jeremy Jonas
πŸ’»
Matt Martz
πŸ’»
Max KΓΆrlinge
πŸ’»
Neil Kuan
πŸ’»
Rafal Wilinski
πŸ’»
Romain Marcadier
πŸ’»
Thomas Klinger
πŸ’»

Tobias
πŸ’»
flyingImer
πŸ’»
Aatman
πŸ’»
Mark McCulloh
πŸ’»
Samuel Tschiedel
πŸ’»
Eli Polonsky
πŸ’»
Alexander Steppke
πŸ’»

Balagopal Kanattil
πŸ’»
Jan Brauer
πŸ’»
Mark Nielsen
πŸ’»
Mitchell Valine
πŸ’»
Neil Kuan
πŸ’»
Philipp Garbe
πŸ’»
Shawn MacIntyre
πŸ’»

Tobias
πŸ’»
Yigong Liu
πŸ’»
Eduardo Rodrigues
πŸ’»
Hassan Azhar
πŸ’»
Julian Michel
πŸ’»
lmarsden
πŸ’»
Adrian Mace
πŸ’»

Heiko Rothe
πŸ’»
Henri Yandell
πŸ’»
Matthew Gamble
πŸ’»
Will Dady
πŸ’»
Matteo Sessa
πŸ’»
Juho Saarinen
πŸ’»
Nick Lynch
πŸ’»

License

Distributed under the Apache-2.0 license.

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