plugin-sdk

jasper-plugin-sdk

SDK for writing Jasper plugins in Rust, compiled to wasm32-unknown-unknown and run inside the host's wasmi sandbox.

The crate's minor version tracks the plugin API spec version (SDK 0.2.x ⇔ apiVersion = "0.2" in manifest.toml). The full contract lives in docs/plugin-spec.md.

Quick start

[lib]
crate-type = ["cdylib"]

[dependencies]
jasper-plugin-sdk = "0.2"

use jasper_plugin_sdk as sdk;
use sdk::core::model::Note;

fn before_save(mut note: Note) -> Result<Note, String> {
    note.body = note.body.lines().map(|l| l.trim_end()).collect::<Vec<_>>().join("\n");
    Ok(note)
}

sdk::register! { before_save: before_save }

Build with cargo build --release --target wasm32-unknown-unknown, then zip manifest.toml + plugin.wasm (+ assets) into a .jplug package.

What you get

• register! — wires your code to the wasm ABI (plugin_dispatch); the three slots before_save, storage, command can be combined freely
• host — typed wrappers over host_call: log, now_ms (the sandbox has no clock), settings_get/settings_set (needs settings capability), http_request (needs host:http capability)
• storage::Storage — implement this trait to provide a storage backend (declared via [[contributes.storage]] in the manifest)
• sdk::core — re-export of jasper-core model types crossing the ABI

Testing your plugin natively

Plain unit tests just work (cargo test — the ABI exports are wasm-only). For integration tests that need host APIs, enable the native-host feature in dev-dependencies: host_call is then served by a local stand-in — http.request performs real HTTP via ureq, time.now uses the system clock, and settings live in a thread-local map you can seed with sdk::native_host::set_setting:

[dev-dependencies]
jasper-plugin-sdk = { version = "0.2", features = ["native-host"] }

This is a test double, not the sandbox: no capability gating, no fuel/memory limits. It never affects the wasm build.

Gotchas

• Don't pull dependencies that drag in wasm-bindgen (e.g. chrono with default features) — the sandbox is plain wasm, not a JS environment. The SDK registers a getrandom error stub so wasm32-unknown-unknown links.
• Reference plugins live in plugins-examples/ (before-save hook, storage providers, editor command).

License

MIT OR Apache-2.0, at your option.