LiveView Native Core

This repository contains an implementation of the LiveView Native core library, which is intended to handle all the details which are common across the various platforms on which LiveView Native is used.

This project is primarily meant for use as a static library via uniffi generated client libraries. This project can also be used as a crate dependency but it is not the first priority.

Features

Currently, the features planned to be provided by the Core library consists of:

1. Connection management for the LiveView socket
2. Initializing a virtual DOM from the page received from the LiveView server, and associated parsing out of components, live views, and statics
3. Receipt, decoding, and application of changes sent by the LiveView server to the virtual DOM managed by Core
4. Management of callbacks/event handlers registered from the host language in response to virtual DOM changes

Host languages (e.g. Swift) can then bind to this library, and focus on the details of rendering the UI, rather than on how to interact with the LiveView server.

Status

This library is not quite ready for production use yet, as there are still some details of the API being finalized, and much testing remains to be done. We'll plan to announce the library more publicly when it is ready for the community to build with.

Client libraries

This project generates bindings for Kotlin and Swift via uniffi. The Swift package is bundled in with an xcframework with the pre-compiled static libraries for all supported Apple targets. The Kotlin package is similar.

C# bindings with the goal of supporting WinUI3 could be in the future of this project.

Development

Building liveview-native-core for watchOS, tvOS, and visionOS depends on the build-std unstable rust feature because they are tier-3 rust targets thus the nightly rust compiler is required. Various language nightly features have been added at times but it's a goal to reduce those and only use stable language features.

To run tests, you will want to start the test server via:

mix deps.get && mix compile && mix phx.server

To run cargo test, you need to have kotlinx-coroutines-core-jvm.jar and jna-5.14.0.jar (or similar) in the CLASSPATH.

Rust integration tests are ran in various simulators via cargo-dinghy. Dinghy can be described as a more or less cursed way to run tests. It attaches to the simulator process via lldb to get the status code of the program - this requires sudo in some cases. The current project setup uses custom target runners to enable the rust tests to be packaged into a apple simulator app. Annoyingly this can be flakey in CI.

Android/Kotlin Notes

For cargo test to succeed, you will need the kotlin brew package or equivalent and possibly ktlint.

In the liveview-native-core-jetpack directory you'll find instructions/requirements for building the jetpack client.

Apple/Swift Notes

Installation of the xcode and iOS/watchOS/tvOS/visionOS platforms is required to build for various platforms.

This project currently relies heavily on cargo-make for the Apple target builds (xcframework, swift package, etc.). It is subject to change but cargo make uniffi-swift-test will build the xcframework (cargo make uniffi-xcframework), package up the swift package (cargo make uniffi-swift-package) and test all the supported apple platforms - Swift, Apple TV, Apple Watch, Apple Vision Pro, iPhone, MacOS.

At the moment, cargo make uniffi-swift-test requires the CARGO_MAKE_TOOLCHAIN to be set. This is useful should you need have a custom toolchain of the rust compiler. Tier-3 rust targets can break from time to time.

The Package.swift is at the root of the project but the package contents are located in the ./crates/core/liveview-native-core-swift subdirectory. This is because swift packages are used as git repos and possibly do not support subdirectory packages.

The various sub-tests cargo make uniffi-swift-test-{package, macos, etc} do not build the swift package or the xcframework. This is is because the swift_integration_tests run on an action matrix and depend on swift_build_xcframework.

Releases

To create a Release, one must navigate to the Releases pane of the GitHub UI and create a new pre-release with a tag. This will kick off the release CI which compiles the rust into many static libraries, generates swift and bundles it all into a swift package that is consumable by liveview-client-swiftui.

License

MIT. See LICENSE.md.