Hello world :: Spin

Spin is a way to deploy serverless WebAssembly (WASM) apps

The purpose of this repo is to try out Fermyon Spin while building a simple Rust app.

Since wasm/wasi/wati are all evolving standards, there are some complications, but theoretically any language that compiles to WASM could be used.

Installation

Install Spin

curl https://developer.fermyon.com/downloads/install.sh | bash

Build and serve app locally

Export an ENV variable for your mysql connection

export SPIN_CONFIG_DB_URL="your conn url"

Start up the app in the same terminal

spin build --up

And we'll see:

Logging component stdio to ".spin/logs/"

Serving http://127.0.0.1:3000
Available Routes:
  hello-rust: http://127.0.0.1:3000 (wildcard)

Issues

• Spin doesn't support TLS for mysql connection? But Planetscale requires TLS... still looking into this one

• If you try to connect to a mysql url with the parameter tls, you'll see 5(?!) errors per request

  thread 'tokio-runtime-worker' panicked at 'called `Result::unwrap()` on an `Err` value: UnknownParameter { param: "tls" }', /Users/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/mysql_async-0.30.0/src/opts.rs:843:41
  

Interesting references

• [https://www.thorsten-hans.com/master-configuration-data-in-fermyon-spin/]