theetrain / bit

Share code components with your team across projects

Bit

Website & community • Short video • Demo project • Demo collection

Bit is a fast and powerful way to share and sync source code components between different SCM repositories and projects. As a nearly-seamless extension for your Git workflow, it enables you to tag and share components directly from your project's repository and install them in other projects while keeping them synced.

You can download and add Bit to any project or library you want to share components from. Adding Bit to any project, existing or new, will not change its src code. Bit works great for React or Angular components, Node modules, utility functions and more.

• Tag and share any subset of files as a reusable component directly from your project's repository, without changing your source code or file structure. Share multiple components in seconds and sync them across projects.

• Organize and discover components shared and loved by your team. Determine and monitor component quality through auto-generated docs, test results and visual rendering.

• Gain universal control over your dependency graph. Commit and test vast dependency changes at once. Build and test any component in any application environment.

• Coming soon: Install components with NPM and Yarn.

Bit is an open-source collaborative project, actively maintained by a full-time venture-backed team and used by organizations and open source teams.

Demos & Tutorials

1. A collection of React movie-app components on the free Bit community hub.
2. A matching React component library with Bit.
3. A short demo video.
4. A quick-start tutorial for Bit with React components.

Supported Languages

Bit is language agnostic. Still, it requires binding and additional language sensitive features for different programming languages. To do this, Bit uses language-specific drivers:

• bit-javascript

Quick Start

• You can find the full getting started guide here.
• You can find a list of command examples here.

Install Bit

See different install methods for different operation systems.

Initialize Bit

To start tracking even the most simple of components, we will need to create a workspace (local Scope) for your project. Use the local scope to organize and track the code components within your project.

To create a local Bit Scope for your project, run this command:

bit init

Create a Simple Component

A Bit component can be a React or Angular component or any other Javascript component. The simplest Bit component is a single file, with zero dependencies. Let's create a simple JavaScript module. Create a file called index.js and paste the following code in the file:

/**
 * Vaildates if input is string- throws exception if not
 * @param {string} name
 * @returns bool
 * @example
 * ```js
 * isString(str)
 * ```
 */
module.exports = function isString(input) {
  if (typeof input !== 'string') {
    throw new TypeError('Not a valid string');
  }
};

Let's track our component, and name it 'utils/is-string'.

bit add index.js -i utils/is-string

You can also use glob patterns to track a group of components together.

Now run a quick bit status command to validate that utils/is-string is being tracked.

Tag a Component

Now, let's Tag the newly tracked component. Tagging a component will lock of all its dependencies (in this case we have none), and create a version for the component.

bit tag -am 'initial version'

Another quick bit status command will show that the component is now staged, and ready to be exported.

Create a Scope

Components are shared into playlist-like collections called Scopes. A scope is a collection of shared components with a common theme or ownership. Scopes allow you to organize and maintain components in a single location, while individually installing and updating them. They also act as a registry for the components it hosts.

Scopes are super lightweight and can be set up on any server, in any location.

You can also freely host your Scopes on the Bit community hub, BitSrc.

For this quick-start guide, let's connect to to BitSrc and create a Scope.

Export Components

After creating a Scope, run the export command. This will publish your components and make them available to share in other projects:

bit export <username>.<scopename>

And you're done!
Browse your Scope and your different components which are now available for import.

You can check out an example or React movie-app components exported to BitSrc here.

Import Components

Bit enables you to import individual components to use in your different projects.
You can install a component as an application part in any destination on your project’s file system.

Let's import the components we just created to a new project.

1. Create a new directory for the consuming project.
2. Initialize a new scope using the bit init command.
3. Import the component:

bit import <username>.<scopename>/utils/is-string

You can now use the component in your new project:

const component = require('./components/utils/is-string');
# 'components' is the default location for imported components

Updating Components

Components can be updated from any project which is using them.

To update a component, simply change the code from inside your project's context. Afterwards tag it again, and export it back to your Scope as a new version of your component.

1. Open the file you just imported.
2. Make any change in it.
3. Run the bit status command to check that utils/is-string has been modified.
4. Tag a new version for the component:

bit tag -am "updated component"

5. Export the new version of the component back to the Scope:

bit export <username>.<scopename>

Now you can go back to your browser, and see that there's a new version for utils/is-string with the changes we've made from the consumer project.

Why Bit

Achieving true modularity with reusable and encapsulated components is a considerable challenge.

With every new feature and every new member joining our team, we found it increasingly hard to share our code and keep it synced between projects. Determined to avoid duplications, we considered many solutions including an arsenal of small repos and packages or creating vast shared static libraries.

However, issues such as the publish overhead, discoverability, and maintainability prevented us from truly sharing and syncing our components as a team between our projects.

Finally, we decided to build our own open-source project that will allow us to share components directly from our SCM repo’s source code, organize them as a team with defined ownership and sync them between different projects. In a way, Bit is a “virtual monorepo” that syncs components on top of our entire codebase, with both multi-repo and mono-repo architectures in mind.

Contributing

Contributions are always welcome, no matter how large or small. Before contributing, please read the code of conduct.

See Contributing.

Feedback

Feedbacks are more than welcome: [email protected] or via Bit's Gitter channel.

License

Apache License, Version 2.0