input_pipeline > Integration

Reviewed on: 2022-03-22

This document describes how to integrate the input pipeline within a larger Rust program. For example, the input pipeline is integrated with

• the Scene Manager for workstation builds,
• the input pipeline component for other builds.

Requirements

The code that deals with the input pipeline must run on a LocalExecutor. For existing code, this is already true. Both //src/ui/bin/input-pipeline and //src/session/bin/scene_manager use fuchsia_async::run_singlethreaded, so they each use a LocalExecutor.

Alternatives

A program might want to isolate itself from the risk that a bug in the input pipeline library (e.g. infinite loop) will keep the rest of the program from making progress. Such programs can

1. Spawn a dedicated thread to run a LocalExecutor which creates and runs the input pipeline, OR
2. Run the input pipeline as a standalone component, and communicate with the pipeline over FIDL.