Function decode

chirpstack/src/codec/js/mod.rs:15–97

(
    recv_time: DateTime<Utc>,
    f_port: u8,
    variables: &HashMap<String, String>,
    decode_config: &str,
    b: &[u8],
)

mod vendor_ieee754;

pub async fn decode(
    recv_time: DateTime<Utc>,
    f_port: u8,
    variables: &HashMap<String, String>,
    decode_config: &str,
    b: &[u8],
) -> Result<pbjson_types::Struct> {
    let conf = config::get();
    let max_run_ts = SystemTime::now() + conf.codec.js.max_execution_time;

    let resolver = rquickjs::loader::BuiltinResolver::default()
        .with_module("base64-js")
        .with_module("ieee754")
        .with_module("buffer");
    let loader = rquickjs::loader::BuiltinLoader::default()
        .with_module("base64-js", vendor_base64_js::SCRIPT)
        .with_module("ieee754", vendor_ieee754::SCRIPT)
        .with_module("buffer", vendor_buffer::SCRIPT);

    let rt = rquickjs::Runtime::new()?;
    rt.set_interrupt_handler(Some(Box::new(move || SystemTime::now() > max_run_ts)));
    rt.set_loader(resolver, loader);

    let ctx = rquickjs::Context::full(&rt)?;

    let script = format!(
        r#"
        import {{ Buffer }} from "buffer";

        {}

        export default decodeUplink(chirpstack_input);
        "#,
        decode_config
    );
    let b = b.to_vec();

    let out = ctx.with(|ctx| -> Result<pbjson_types::Struct> {
        let input = rquickjs::Object::new(ctx.clone())?;
        input.set("bytes", b.into_js(&ctx)?)?;
        input.set("fPort", f_port.into_js(&ctx)?)?;
        input.set("recvTime", recv_time.into_js(&ctx)?)?;
        input.set("variables", variables.into_js(&ctx)?)?;
        ctx.globals().set("chirpstack_input", input)?;

        let module = rquickjs::Module::declare(ctx.clone(), "main", script)
            .catch(&ctx)
            .map_err(|e| anyhow!("JS error: {}", e))?;

        let (module, promise) = module
            .eval()
            .catch(&ctx)
            .map_err(|e| anyhow!("JS error: {}", e))?;
        () = promise
            .finish()
            .catch(&ctx)
            .map_err(|e| anyhow!("JS error: {}", e))?;