Our Pledge

In the interest of fostering an open and welcoming environment, we as contributors and maintainers pledge to making participation in our project and our community a harassment-free experience for everyone, regardless of age, body size, disability, ethnicity, sex characteristics, gender identity and expression, level of experience, education, socio-economic status, nationality, personal appearance, race, religion, or sexual identity and orientation.

Our Standards

Examples of behavior that contributes to creating a positive environment include:

• Using welcoming and inclusive language

• Being respectful of differing viewpoints and experiences

• Gracefully accepting constructive criticism

• Focusing on what is best for the community

• Showing empathy towards other community members

Examples of unacceptable behavior by participants include:

• The use of sexualized language or imagery and unwelcome sexual attention or

  advances

• Trolling, insulting/derogatory comments, and personal or political attacks

• Public or private harassment

• Publishing others' private information, such as a physical or electronic

  address, without explicit permission

• Other conduct which could reasonably be considered inappropriate in a

  professional setting

Our Responsibilities

Project maintainers are responsible for clarifying the standards of acceptable behavior and are expected to take appropriate and fair corrective action in response to any instances of unacceptable behavior.

Project maintainers have the right and responsibility to remove, edit, or reject comments, commits, code, wiki edits, issues, and other contributions that are not aligned to this Code of Conduct, or to ban temporarily or permanently any contributor for other behaviors that they deem inappropriate, threatening, offensive, or harmful.

Scope

This Code of Conduct applies both within project spaces and in public spaces when an individual is representing the project or its community. Examples of representing a project or community include using an official project e-mail address, posting via an official social media account, or acting as an appointed representative at an online or offline event. Representation of a project may be further defined and clarified by project maintainers.

Enforcement

Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by contacting the project team at opensource@tinkoff.ru. All complaints will be reviewed and investigated and will result in a response that is deemed necessary and appropriate to the circumstances. The project team is obligated to maintain confidentiality with regard to the reporter of an incident. Further details of specific enforcement policies may be posted separately.

Project maintainers who do not follow or enforce the Code of Conduct in good faith may face temporary or permanent repercussions as determined by other members of the project's leadership.

Attribution

This Code of Conduct is adapted from the Contributor Covenant, version 1.4, available at https://www.contributor-covenant.org/version/1/4/code-of-conduct.html

For answers to common questions about this code of conduct, see https://www.contributor-covenant.org/faq

How the plugin works

1. The plugin analyzes chunks and extracts libraries to separated chunks with disabled tree-shaking (or not?).

2. The plugin teaches entries and runtime to work with shared chunks.

How the app is loaded

1. Entry points and runtime are loaded.

2. Entry point checks if a shared required to run chunks are loaded and notifies the runtime about it.

3. Runtime downloads all not downloaded libraries and marks them as downloaded.

4. Runtime runs an app.

SharedLibraryWebpackPlugin is a webpack plugin for sharing libraries between applications.

Motivation

When the host application loads many micro apps bundled with a webpack, many JavaScript is loaded on a client page. In a perfect world, each app can share its libraries with other apps and meet the requirements:

1. Each app stays self-hosted.

2. Fallbacks for non-loaded packages.

3. Codesharing in runtime.

4. Different library versions work individually.

SharedLibraryWebpackPlugin came to us from a perfect world!

Documentations

1. Installation and configuration

2. How is it works?

3. Sharing and Tree shaking

4. The Plugin API

Demo

There is a host application with two micro-apps. All apps are built with Angular. The client page loads 282.8kB of JavaScript (gzip) when it opens all pages.

We add SharedLibraryWebpackPlugin in each app build for sharing all Angular packages and zone.js.

const {
  SharedLibraryWebpackPlugin,
} = require('@tinkoff/shared-library-webpack-plugin');

module.exports = {
  plugins: [
    new SharedLibraryWebpackPlugin({
      libs: [
        { name: '@angular/core', usedExports: [] },
        { name: '@angular/common', usedExports: [] },
        { name: '@angular/common/http', usedExports: [] },
        { name: '@angular/platform-browser', usedExports: ['DomSanitizer'] },
        { name: '@angular/platform-browser/animations', usedExports: [] },
        { name: '@angular/animations', usedExports: [] },
        { name: '@angular/animations/browser', usedExports: [] },
        'zone.js/dist/zone',
      ],
    }),
  ],
};

After that, the client page loads 174.6kB of JavaScript! It is 38% less!

Contributing

License

SharedLibraryWebpackPlugin

SharedLibraryWebpackPlugin is a class that implements webpack plugin functionality,

Options

libs

new SharedLibraryWebpackPlugin({
    libs: 'lodash'
});

new SharedLibraryWebpackPlugin({
    libs: '@angular/**'
});

new SharedLibraryWebpackPlugin({
    libs: ['@angular/**', 'zone.js/dist/zone']
});

new SharedLibraryWebpackPlugin({
   libs: {name: '@angular/core', chunkName: 'ng', separator: '@'}
});

namespace

{
    namespace: "__shared_libraries__"
}

disableDefaultJsonpFunctionChange

{
    disableDefaultJsonpFunctionChange: false
}

SharedLibrarySearchConfig

SharedLibrarySearchConfig configures the search for sharing library and the formation of a chunk name.

pattern

{
    pattern: "@angular/**"
}

name

{
    name: "@angular/core"
}

chunkName

{
    chunkName: "ng"
}

suffix

{
    suffix: 'suffix'
}

separator

{
    separator: "@"
}

deps

new SharedLibraryWebpackPlugin({
   libs: [
      '@angular/**', 
      {name: '@tinkoff/angular-ui', deps: ['@angular/core']}
   ]
})

usedExports

{name: '@angular/core', usedExports: ['DomSanitizer']}

Thank you for considering contributing to our project. Your help if very welcome!

When contributing, it's better to first discuss the change you wish to make via issue, email, or any other method with the owners of this repository before making a change.

All members of our community are expected to follow our Code of Conduct. Please make sure you are welcoming and friendly in all of our spaces.

Getting started

In order to make your contribution please make a fork of the repository. After you've pulled the code, follow these steps to kick start the development:

1. Run npm i to install dependencies

2. Run npm start to launch demo project where you could test your changes

3. Use following commands to ensure code quality

npm run lint
npm run build
npm run test

Pull Request Process

1. We follow Conventional Commits

   in our commit messages, i.e. feat(core): improve typing

2. Update README.md to reflect changes related to public API and everything relevant

3. Make sure you cover all code changes with unit tests

4. When you are ready, create Pull Request of your fork into original repository

Version 2.0, January 2004

Apache License

http://www.apache.org/licenses/

TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION

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   "Contribution" shall mean any work of authorship, including the original version of the Work and any modifications or additions to that Work or Derivative Works thereof, that is intentionally submitted to Licensor for inclusion in the Work by the copyright owner or by an individual or Legal Entity authorized to submit on behalf of the copyright owner. For the purposes of this definition, "submitted" means any form of electronic, verbal, or written communication sent to the Licensor or its representatives, including but not limited to communication on electronic mailing lists, source code control systems, and issue tracking systems that are managed by, or on behalf of, the Licensor for the purpose of discussing and improving the Work, but excluding communication that is conspicuously marked or otherwise designated in writing by the copyright owner as "Not a Contribution."

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   You may add Your own copyright statement to Your modifications and may provide additional or different license terms and conditions for use, reproduction, or distribution of Your modifications, or for any such Derivative Works as a whole, provided Your use, reproduction, and distribution of the Work otherwise complies with the conditions stated in this License.

5. Submission of Contributions. Unless You explicitly state otherwise, any Contribution intentionally submitted for inclusion in the Work by You to the Licensor shall be under the terms and conditions of this License, without any additional terms or conditions. Notwithstanding the above, nothing herein shall supersede or modify the terms of any separate license agreement you may have executed with Licensor regarding such Contributions.

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8. Limitation of Liability. In no event and under no legal theory, whether in tort (including negligence), contract, or otherwise, unless required by applicable law (such as deliberate and grossly negligent acts) or agreed to in writing, shall any Contributor be liable to You for damages, including any direct, indirect, special, incidental, or consequential damages of any character arising as a result of this License or out of the use or inability to use the Work (including but not limited to damages for loss of goodwill, work stoppage, computer failure or malfunction, or any and all other commercial damages or losses), even if such Contributor has been advised of the possibility of such damages.

9. Accepting Warranty or Additional Liability. While redistributing the Work or Derivative Works thereof, You may choose to offer, and charge a fee for, acceptance of support, warranty, indemnity, or other liability obligations and/or rights consistent with this License. However, in accepting such obligations, You may act only on Your own behalf and on Your sole responsibility, not on behalf of any other Contributor, and only if You agree to indemnify, defend, and hold each Contributor harmless for any liability incurred by, or claims asserted against, such Contributor by reason of your accepting any such warranty or additional liability.

END OF TERMS AND CONDITIONS

Copyright 2020 Tinkoff Bank

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Installation

The plugin can install by any package manager.

npm i @tinkoff/shared-library-webpack-plugin -D

or

yarn add @tinkoff/shared-library-webpack-plugin --dev

Configuration

Add plugin to webpack configuration file and set a list of libraries for sharing. There is an example with lodash:

import { SharedLibraryWebpackPlugin } from '@tinkoff/shared-library-webpack-plugin';

module.exports = {
  plugin: [
    new SharedLibraryWebpackPlugin({
      libs: 'lodash',
    }),
  ],
};

The plugin adds one more chunk with a hashed name to the bundle. It should be a shared lodash. When the application is loaded, the webpack runtime will check if lodash is loaded.

How does it work?

Tree shaking is dead-code elimination. Read more

Because the plugin doesn't know which the library part will use in another application, it disabled tree shaking. Therefore bundles become large.

For the solution, the plugin provides an usedExports option. It can be an array of import names to be used by another application. See the example in the demo.