add Slight 102

workshop/optional-05-slight-101.md

@@ -67,6 +67,148 @@ slight -c slightfile.toml run target/wasm32-wasi/debug/spidey.wasm
 Hello, SpiderLightning!
 ```
 
+### Slight keyvalue with Redis
+
+Add http server capability
+```
+cd wit && slight add [email protected]
+cd ..
+```
+
+Modify the `src/main.rs` file to `src/lib.rs` and change to the following code:
+
+```rust
+use anyhow::Result;
+
+use http_server::*;
+use keyvalue::*;
+use slight_http_handler_macro::register_handler;
+use slight_http_server_macro::on_server_init;
+
+wit_bindgen_rust::import!("wit/http-server.wit");
+wit_bindgen_rust::export!("wit/http-server-export.wit");
+wit_bindgen_rust::import!("wit/keyvalue.wit");
+wit_error_rs::impl_error!(http_server::HttpRouterError);
+wit_error_rs::impl_error!(keyvalue::KeyvalueError);
+
+#[on_server_init]
+fn main() -> Result<()> {
+    let router = Router::new()?;
+    let router_with_route = router
+        .get("/hello", "handle_hello")?
+        .get("/get", "handle_get")?
+        .put("/set", "handle_set")?;
+
+    println!("Server is running on port 3000");
+    let _ = Server::serve("0.0.0.0:3000", &router_with_route)?;
+    Ok(())
+}
+
+#[register_handler]
+fn handle_hello(req: Request) -> Result<Response, HttpError> {
+    println!("I just got a request uri: {} method: {}", req.uri, req.method);
+    Ok(Response {
+        headers: Some(req.headers),
+        body: Some("hello".as_bytes().to_vec()),
+        status: 200,
+    })
+}
+
+#[register_handler]
+fn handle_get(request: Request) -> Result<Response, HttpError> {
+    let keyvalue =
+        Keyvalue::open("my-container").map_err(|e| HttpError::UnexpectedError(e.to_string()))?;
+
+    match keyvalue.get("key") {
+        Err(KeyvalueError::KeyNotFound(_)) => Ok(Response {
+            headers: Some(request.headers),
+            body: Some("Key not found".as_bytes().to_vec()),
+            status: 404,
+        }),
+        Ok(value) => Ok(Response {
+            headers: Some(request.headers),
+            body: Some(value),
+            status: 200,
+        }),
+        Err(e) => Err(HttpError::UnexpectedError(e.to_string())),
+    }
+}
+
+#[register_handler]
+fn handle_set(request: Request) -> Result<Response, HttpError> {
+    assert_eq!(request.method, Method::Put);
+    if let Some(body) = request.body {
+        let keyvalue = Keyvalue::open("my-container")
+            .map_err(|e| HttpError::UnexpectedError(e.to_string()))?;
+        keyvalue
+            .set("key", &body)
+            .map_err(|e| HttpError::UnexpectedError(e.to_string()))?;
+    }
+    Ok(Response {
+        headers: Some(request.headers),
+        body: None,
+        status: 204,
+    })
+}
+```
+
+Next, change Cargo.toml to the following code:
+
+```toml
+[package]
+name = "spidey"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+[lib]
+crate-type = ["cdylib"]
+
+[dependencies]
+anyhow = "1"
+wit-bindgen-rust = { git = "https://github.com/fermyon/wit-bindgen-backport" }
+wit-error-rs = { git = "https://github.com/danbugs/wit-error-rs", rev = "05362f1a4a3a9dc6a1de39195e06d2d5d6491a5e" }
+slight-http-handler-macro = { git = "https://github.com/deislabs/spiderlightning", tag = "0.4.1" }
+slight-http-server-macro = { git = "https://github.com/deislabs/spiderlightning", tag = "0.4.1" }
+
+```
+
+Last, add the following capability the slightfile.toml
+
+```toml
+[[capability]]
+resource = "keyvalue.redis"
+name = "my-container"
+    [capability.configs]
+    REDIS_ADDRESS = "redis://127.0.0.1:6379"
+```
+
+### Build and Run
+
+```bash
+cargo build --target wasm32-wasi
+```
+
+Start a local redis server
+
+```bash
+redis-server --port 6379
+```
+
+Run the slight
+
+```bash
+slight -c slightfile.toml run target/wasm32-wasi/debug/spidey.wasm
+```
+
+### Test
+
+```bash
+curl -X PUT http://localhost:3000/set -d "hello"
+
+curl http://localhost:3000/get
+```
+
 ### Try out other slight capabilities
 
 1. [Keyvalue](https://github.com/deislabs/spiderlightning/tree/main/examples/keyvalue-demo)