whisker-dev-server 0.2.0

Host-side dev server for `whisker run`. File watch + cargo build + WebSocket push of subsecond patches. Pulled in by whisker-cli; no presence in release builds.
Documentation

Host-side dev server for whisker run.

Owns the long-running dev loop: file watch, cargo rebuild, install to the device, subsecond patch construction, and WebSocket push. whisker-cli's run subcommand is a thin wrapper that builds a [Config] and calls [DevServer::run] — every piece of UX-shaped logic lives here so future host shells (an editor plugin, a notebook, a remote-controlled CI build) can reuse it.

Architecture

Constructed once via [Config], the dev server spins up six cooperating pieces:

  • builder — translates [Config] into a whisker-build invocation (cargo + per-platform packaging) and runs it. Honours RUSTC_WORKSPACE_WRAPPER + linker shim env so the fat build doubles as a capture pass for Tier 1.
  • installer — for the cold-rebuild path: shells out to adb install / simctl install + launch. Identity (bundle id, applicationId, scheme, …) comes in flat via [AndroidParams] / [IosParams]; the cli resolves these from the user's whisker.rs::configure(&mut Config). This crate never depends on whisker-config.
  • watcher — notify-based, debounced, classifies events into ChangeKind::{RustCode, CargoToml, Other}.
  • server — axum WebSocket endpoint at ws://<bind>/whisker-dev. Devices dial in, send a hello carrying their subsecond::aslr_reference(), then receive patch envelopes.
  • hotpatch — Tier 1 implementation. Builds a thin .o from the changed user crate via captured rustc args, links it into a patch dylib with a stub-object of host-symbol jumps, ships the resulting subsecond_types::JumpTable to connected clients.
  • lib.rs::run — the orchestrator: file event → decide_action (Tier 1 patch vs Tier 2 rebuild) → builder/hotpatch/sender.

Layering

Stays manifest-agnostic on purpose. The cli does the whisker.rs → Config translation; this crate accepts only flat String / PathBuf fields. That keeps the dev-server reusable from any host shell that can produce the same flat Config (the cli is one; an editor plugin could be another).