add support for wasi:http/[email protected] (#2166)

* add support for `wasi:http/[email protected]`

This builds upon Alex's excellent work in
#2108, adding the ability to run guests
which target the `0.2.0-rc-2023-11-10` version of `wasi-http`.

I've added a test which uses `wit-bindgen` and `wit-component` directly to
ensure it uses the correct snapshot for everything `wasi-http`, `wasi-cli`, etc.

Note that we're not yet updating any SDKs to use the new snapshot, since we
still want people to be able to use the new SDK to target Spin 2.0.

Signed-off-by: Joel Dice <[email protected]>

* use different names for `wasi-http-rust-rc-2023-11-10` module and component

Previously, I tried to be clever and overwrite the module with the component,
but that led to a filesystem-level race condition and was just generally
fragile.

Signed-off-by: Joel Dice <[email protected]>

---------

Signed-off-by: Joel Dice <[email protected]>

Cargo.toml

@@ -100,6 +100,7 @@ vergen = { version = "^8.2.1", default-features = false, features = [
   "gitcl",
   "cargo",
 ] }
+wit-component = "0.19.0"
 
 [features]
 default = ["llm"]

build.rs

@@ -13,6 +13,7 @@ const RUST_HTTP_VAULT_VARIABLES_TEST: &str = "tests/http/vault-variables-test";
 const TIMER_TRIGGER_INTEGRATION_TEST: &str = "examples/spin-timer/app-example";
 const WASI_HTTP_INTEGRATION_TEST: &str = "examples/wasi-http-rust-streaming-outgoing-body";
 const OUTBOUND_HTTP_POST_INTEGRATION_TEST: &str = "examples/http-rust-outbound-post";
+const WASI_HTTP_RC_11_10_INTEGRATION_TEST: &str = "tests/http/wasi-http-rust-0.2.0-rc-2023-11-10";
 
 fn main() {
     // Extract environment information to be passed to plugins.
@@ -92,6 +93,33 @@ error: the `wasm32-wasi` target is not installed
     cargo_build(TIMER_TRIGGER_INTEGRATION_TEST);
     cargo_build(WASI_HTTP_INTEGRATION_TEST);
     cargo_build(OUTBOUND_HTTP_POST_INTEGRATION_TEST);
+    cargo_build(WASI_HTTP_RC_11_10_INTEGRATION_TEST);
+
+    // Rather than let `spin-componentize` turn the `WASI_HTTP_RC_11_10_INTEGRATION_TEST` module into a component,
+    // we use Wasmtime 15.0.1's adapter to ensure it uses the WASI 0.2.0-rc-2023-11-10 snapshot for everything.
+    let wasi_http_rc_11_10_module = format!(
+        "{WASI_HTTP_RC_11_10_INTEGRATION_TEST}/target/wasm32-wasi/release/wasi_http_rust_rc_2023_11_10.wasm"
+    );
+    let wasi_http_rc_11_10_adapter =
+        format!("{WASI_HTTP_RC_11_10_INTEGRATION_TEST}/wasi_snapshot_preview1.reactor.wasm");
+    let wasi_http_rc_11_10_component = format!(
+        "{WASI_HTTP_RC_11_10_INTEGRATION_TEST}/target/wasm32-wasi/release/wasi_http_rust_rc_2023_11_10.component.wasm"
+    );
+    std::fs::write(
+        wasi_http_rc_11_10_component,
+        wit_component::ComponentEncoder::default()
+            .validate(true)
+            .module(&std::fs::read(wasi_http_rc_11_10_module).unwrap())
+            .unwrap()
+            .adapter(
+                "wasi_snapshot_preview1",
+                &std::fs::read(wasi_http_rc_11_10_adapter).unwrap(),
+            )
+            .unwrap()
+            .encode()
+            .unwrap(),
+    )
+    .unwrap();
 }
 
 fn build_wasm_test_program(name: &'static str, root: &'static str) {

crates/trigger-http/src/handler.rs

@@ -51,7 +51,10 @@ impl HttpExecutor for HttpHandlerExecutor {
                     .await
                     .map_err(contextualise_err)?
             }
-            None => bail!("Expected component to either export `{}` or `fermyon:spin/inbound-http` but it exported neither", WASI_HTTP_EXPORT)
+            None => bail!(
+                "Expected component to either export `{WASI_HTTP_EXPORT_2023_10_18}`, \
+                 `{WASI_HTTP_EXPORT_2023_11_10}`, or `fermyon:spin/inbound-http` but it exported neither"
+            )
         };
 
         tracing::info!(
@@ -302,12 +305,15 @@ enum HandlerType {
     Wasi,
 }
 
-const WASI_HTTP_EXPORT: &str = "wasi:http/[email protected]";
+const WASI_HTTP_EXPORT_2023_10_18: &str = "wasi:http/[email protected]";
+const WASI_HTTP_EXPORT_2023_11_10: &str = "wasi:http/[email protected]";
 
 impl HandlerType {
     /// Determine the handler type from the exports
     fn from_exports(mut exports: wasmtime::component::Exports<'_>) -> Option<HandlerType> {
-        if exports.instance(WASI_HTTP_EXPORT).is_some() {
+        if exports.instance(WASI_HTTP_EXPORT_2023_10_18).is_some()
+            || exports.instance(WASI_HTTP_EXPORT_2023_11_10).is_some()
+        {
             return Some(HandlerType::Wasi);
         }
         if exports.instance("fermyon:spin/inbound-http").is_some() {

tests/http/wasi-http-rust-0.2.0-rc-2023-11-10/.cargo/config.toml

@@ -0,0 +1,2 @@
+[build]
+target = "wasm32-wasi"