init plugins

wasm/oxicloud-plugin-hello/src/lib.rs

@@ -0,0 +1,75 @@
+//! Example OxiCloud plugin — ABI v0 (M0 walking skeleton).
+//!
+//! The default build is the well-behaved "hello" plugin: it reads the
+//! `file.uploaded` event metadata, calls the host `log` function (the only
+//! authority a plugin has), and returns `{"ok": true}`.
+//!
+//! Cargo features select the misbehaving variants the host's failure-isolation
+//! tests load (`panic`, `sleep`, `net`, `wrong_abi`). See
+//! `scripts/build-plugin-hello.sh`.
+
+use extism_pdk::*;
+
+/// The one host function OxiCloud exposes, imported from its namespaced module.
+#[host_fn("oxicloud:host:v0")]
+extern "ExtismHost" {
+    fn log(level: String, message: String);
+}
+
+/// Required export: which ABI this plugin was built against. The host rejects
+/// the plugin at load if this does not equal its own `OXICLOUD_PLUGIN_ABI`.
+#[cfg(not(feature = "wrong_abi"))]
+#[plugin_fn]
+pub fn abi_version() -> FnResult<u32> {
+    Ok(0)
+}
+
+/// `wrong_abi` variant: claim an ABI the host does not speak.
+#[cfg(feature = "wrong_abi")]
+#[plugin_fn]
+pub fn abi_version() -> FnResult<u32> {
+    Ok(1)
+}
+
+/// Required export: the single event entry point.
+#[plugin_fn]
+pub fn handle(input: String) -> FnResult<String> {
+    // --- misbehaving variants (compiled in only under their feature) ---------
+    #[cfg(feature = "panic")]
+    panic!("intentional panic: exercises host failure isolation");
+
+    #[cfg(feature = "sleep")]
+    {
+        // Busy-loop forever; the host's wall-clock timeout must cancel us.
+        let mut spin: u64 = 0;
+        loop {
+            spin = spin.wrapping_add(1);
+            std::hint::black_box(spin);
+        }
+    }
+
+    #[cfg(feature = "net")]
+    {
+        // Attempt an outbound HTTP call. The host grants no `allowed_hosts`, so
+        // Extism denies this before any socket is opened (offline-deterministic)
+        // and the error propagates out of `handle`.
+        let req = HttpRequest::new("https://example.com/");
+        let _ = http::request::<()>(&req, None)?;
+    }
+
+    // --- well-behaved "hello" path ------------------------------------------
+    let ev: serde_json::Value = serde_json::from_str(&input)?;
+    let path = ev["payload"]["path"].as_str().unwrap_or("<unknown>");
+    let size = ev["payload"]["size"].as_u64().unwrap_or(0);
+
+    // Prove plugin -> host: call the only authority we have.
+    unsafe {
+        log(
+            "info".to_string(),
+            format!("hello plugin saw upload: {path} ({size} bytes)"),
+        )?;
+    }
+
+    // Prove plugin -> host return path.
+    Ok(serde_json::json!({ "ok": true }).to_string())
+}