Hello Wasm Cloudflare

Fun Facts

• You can use js or rs or both js+rs. // js has more examples/features complete than rs.
• You can call worker from pages. // Think CMS with backend-less which can hydrate/dehydrate anywhere you desire.
• You can make and modify request/response.
• 🦀 You can fetch through reqwest or worker::Fetch::Request. // See example below. 👇

How to fetch and response as json with reqwest

use worker::*;

pub async fn fetch_json(url: &str) -> anyhow::Result<serde_json::Value> {
    Ok(reqwest::get(url).await?.json().await?)
}

#[event(fetch)]
pub async fn main(_: Request, _: Env, _: Context) -> Result<Response> {
    let url = "https://raw.githubusercontent.com/gist-rs/book/main/examples/r4/20-fetch-json-reqwest/src/foo.json";
    let json_result = fetch_json(url).await;

    match json_result {
        Ok(value) => Response::ok(value.to_string()),
        Err(err) => Response::error(format!("${err}"), 500),
    }
}

💡 For more reqwest example see here

How to fetch with upgrade websocket via worker::Fetch::Request

🤔 Refer to Cloudflare issue

use worker::*;

#[event(fetch)]
pub async fn main(_: Request, _: Env, _: Context) -> Result<Response> {
    let url = "https://httpbin.org/anything";

    let mut headers = Headers::new();
    headers.set("Upgrade", "websocket")?;

    let request = Request::new_with_init(
        url,
        RequestInit::new().with_headers(headers)
    )?;

    Fetch::Request(request).send().await
}