Waxosuit Key-Value Tutorial

waxtut_kv_lib.rs

extern crate wascap_guest as guest;

#[macro_use]
extern crate serde_derive;

use guest::prelude::*;

call_handler!(handle_call);

pub fn handle_call(ctx: &CapabilitiesContext, operation: &str, msg: &[u8]) -> CallResult {
    match operation {
            http::TYPE_URL_HTTP_REQUEST => handle_counter(ctx, msg),
            core::TYPE_URL_HEALTH_REQUEST => Ok(vec![]),
            _ => Err("bad dispatch".into()),
    }
}

fn handle_counter(ctx: &CapabilitiesContext, payload: impl Into<http::Request>) -> CallResult {
    let req = payload.into();
    match req.method.as_ref() {
        "GET" => query_counter(ctx.kv()),
        _ => increment_counter(ctx.kv()),
    }
}

fn query_counter(kv: &KeyValueStore) -> CallResult {
    let val: i32 = kv.get("demo:counter")?.unwrap().parse().unwrap();

    Ok(protobytes(http::Response::json(CounterData { counter: val }, 200, "OK")?)
}

fn increment_counter(kv: &KeyValueStore) -> CallResult {
    kv.atomic_add("demo:counter", 1)?;

    Ok(protobytes(http::Response::ok()?)
}

#[derive(Debug, Serialize)]
struct CounterData {
    counter: i32,
}