Moti Zilberman
7886abd243
Summary: Pull Request resolved: https://github.com/facebook/react-native/pull/42397 Changelog: [Internal] Adds a stub `PageTarget` class to serve as the entry point to the modern CDP backend in React Native. The primary method exposed by `PageTarget` is `connect()` which is designed to fit directly as a connection callback passed to `InspectorPackagerConnection::addPage()`. This constructs a `PageTargetSession` containing a `PageAgent` where the actual CDP message handling/routing will occur. For now, `PageAgent` implements no CDP methods, and always responds with a "not implemented" error. Basic unit tests are included, though we might want to migrate to a more integration-style test suite (with fewer mocks and real bindings to RN) once we've implemented more of the protocol. ## What is a Page In Chrome's implementation of CDP, a Page represents a single browser tab. A Chrome DevTools session connects to one Page at a time (though it can potentially inspect multiple JavaScript contexts owned by that Page, such as those found in frames and workers). In our system, a Page will correspond 1:1 to React Native's concept of a *Host* (implemented as `RCTHost`, `RCTBridge`, `ReactHostImpl` or `ReactInstanceManager`, depending on the platform). In all cases, the Host is the object that has a stable identity across reloads, and manages the lifetime of an *Instance* where the JSVM and other application state lives. There can be multiple Hosts in a React Native process, though this is somewhat unusual; those would be treated as independent "tabs" from the perspective of the debugger. NOTE: The concepts of Target, Session and Agent are new (to this codebase) and are *broadly* inspired by the [corresponding Chromium / V8 concepts](https://chromium.googlesource.com/chromium/src/+/master/third_party/blink/public/devtools_protocol/#Agents_Targets-and-Sessions), though some details differ. ## Next steps Each core platform implementation in React Native (iOS Bridgeless, iOS Bridge, Android Bridgeless, Android Bridge), as well as out-of-tree platforms that want to support the new debugger, will need to create and register a `PageTarget` instance. We'll do this piecemeal in subsequent diffs. We'll also gradually add APIs and logic to `PageTarget` / `PageAgent` to allow us to implement some "interesting" CDP methods - some of them directly (e.g. handling reload commands) and others by dispatching to nested agents (e.g. a JS debugging agent powered by Hermes). Reviewed By: huntie Differential Revision: D50936932 fbshipit-source-id: ebe5856d7badb361d4971dd9aabeb9982f8aed1b
React Native
Learn once, write anywhere:
Build mobile apps with React.
Getting Started · Learn the Basics · Showcase · Contribute · Community · Support
React Native brings React's declarative UI framework to iOS and Android. With React Native, you use native UI controls and have full access to the native platform.
- Declarative. React makes it painless to create interactive UIs. Declarative views make your code more predictable and easier to debug.
- Component-Based. Build encapsulated components that manage their state, then compose them to make complex UIs.
- Developer Velocity. See local changes in seconds. Changes to JavaScript code can be live reloaded without rebuilding the native app.
- Portability. Reuse code across iOS, Android, and other platforms.
React Native is developed and supported by many companies and individual core contributors. Find out more in our ecosystem overview.
Contents
- Requirements
- Building your first React Native app
- Documentation
- Upgrading
- How to Contribute
- Code of Conduct
- License
📋 Requirements
React Native apps may target iOS 13.4 and Android 6.0 (API 23) or newer. You may use Windows, macOS, or Linux as your development operating system, though building and running iOS apps is limited to macOS. Tools like Expo can be used to work around this.
🎉 Building your first React Native app
Follow the Getting Started guide. The recommended way to install React Native depends on your project. Here you can find short guides for the most common scenarios:
📖 Documentation
The full documentation for React Native can be found on our website.
The React Native documentation discusses components, APIs, and topics that are specific to React Native. For further documentation on the React API that is shared between React Native and React DOM, refer to the React documentation.
The source for the React Native documentation and website is hosted on a separate repo, @facebook/react-native-website.
🚀 Upgrading
Upgrading to new versions of React Native may give you access to more APIs, views, developer tools, and other goodies. See the Upgrading Guide for instructions.
React Native releases are discussed in this discussion repo.
👏 How to Contribute
The main purpose of this repository is to continue evolving React Native core. We want to make contributing to this project as easy and transparent as possible, and we are grateful to the community for contributing bug fixes and improvements. Read below to learn how you can take part in improving React Native.
Code of Conduct
Facebook has adopted a Code of Conduct that we expect project participants to adhere to. Please read the full text so that you can understand what actions will and will not be tolerated.
Contributing Guide
Read our Contributing Guide to learn about our development process, how to propose bugfixes and improvements, and how to build and test your changes to React Native.
Open Source Roadmap
You can learn more about our vision for React Native in the Roadmap.
Good First Issues
We have a list of good first issues that contain bugs which have a relatively limited scope. This is a great place to get started, gain experience, and get familiar with our contribution process.
Discussions
Larger discussions and proposals are discussed in @react-native-community/discussions-and-proposals.
📄 License
React Native is MIT licensed, as found in the LICENSE file.
React Native documentation is Creative Commons licensed, as found in the LICENSE-docs file.