Workspace skeleton for plugins: sausage-vfs, sausage-interface, sausage-plugin, sausage-plugin-macros

The agent leaves the workspace until it is rewritten on the new SDK.

Cargo.lock

@@ -11,16 +11,6 @@ dependencies = [
  "gimli",
 ]
 
-[[package]]
-name = "agent"
-version = "0.1.0"
-dependencies = [
- "sausage-actor",
- "serde",
- "serde_json",
- "wstd",
-]
-
 [[package]]
 name = "allocator-api2"
 version = "0.2.21"
@@ -95,24 +85,6 @@ version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3bc62ac97cc33321f50863d514c3bc38a453947a8f9e781137e47c7401020aed"
 
-[[package]]
-name = "async-channel"
-version = "2.5.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "924ed96dd52d1b75e9c1a3e6275715fd320f5f9439fb5a4a11fa51f4221158d2"
-dependencies = [
- "concurrent-queue",
- "event-listener-strategy",
- "futures-core",
- "pin-project-lite",
-]
-
-[[package]]
-name = "async-task"
-version = "4.7.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8b75356056920673b02621b35afd0f7dda9306d03c79a30f5c56c44cf256e3de"
-
 [[package]]
 name = "async-trait"
 version = "0.1.92"
@@ -268,15 +240,6 @@ version = "1.0.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1d07550c9036bf2ae0c684c4297d503f838287c83c53686d05370d0e139ae570"
 
-[[package]]
-name = "concurrent-queue"
-version = "2.5.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4ca0197aee26d1ae37445ee532fefce43251d24cc7c166799f4d46817f1d3973"
-dependencies = [
- "crossbeam-utils",
-]
-
 [[package]]
 name = "core_detect"
 version = "1.0.0"
@@ -599,35 +562,6 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
-[[package]]
-name = "event-listener"
-version = "5.4.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5a23add41df1562121a9393cb065eab5146a1242410f23a644851e90cfd669d2"
-dependencies = [
- "parking",
- "pin-project-lite",
-]
-
-[[package]]
-name = "event-listener-strategy"
-version = "0.5.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8be9f3dfaaffdae2972880079a491a1a8bb7cbed0b8dd7a347f668b4150a3b93"
-dependencies = [
- "event-listener",
- "pin-project-lite",
-]
-
-[[package]]
-name = "fastrand"
-version = "1.9.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e51093e27b0797c359783294ca4f0a911c270184cb10f85783b118614a1501be"
-dependencies = [
- "instant",
-]
-
 [[package]]
 name = "fastrand"
 version = "2.5.0"
@@ -723,21 +657,6 @@ version = "0.3.34"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "53c0fa8157de1303bfffdaa1cc2a673bfffb60102f76b0ef4441659124373fed"
 
-[[package]]
-name = "futures-lite"
-version = "1.13.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "49a9d51ce47660b1e808d3c990b4709f2f415d928835a17dfd16991515c46bce"
-dependencies = [
- "fastrand 1.9.0",
- "futures-core",
- "futures-io",
- "memchr",
- "parking",
- "pin-project-lite",
- "waker-fn",
-]
-
 [[package]]
 name = "futures-sink"
 version = "0.3.34"
@@ -1095,15 +1014,6 @@ dependencies = [
  "libc",
 ]
 
-[[package]]
-name = "instant"
-version = "0.1.13"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e0242819d153cba4b4b05a5a8f2a7e9bbf97b6055b2a002b395c96b5ff3c0222"
-dependencies = [
- "cfg-if",
-]
-
 [[package]]
 name = "io-extras"
 version = "0.19.0"
@@ -1370,12 +1280,6 @@ version = "1.70.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "384b8ab6d37215f3c5301a95a4accb5d64aa607f1fcb26a11b5303878451b4fe"
 
-[[package]]
-name = "parking"
-version = "2.2.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f38d5652c16fde515bb1ecef450ab0f6a219d619a7274976324d5e377f7dceba"
-
 [[package]]
 name = "parking_lot"
 version = "0.12.5"
@@ -1687,15 +1591,27 @@ dependencies = [
 ]
 
 [[package]]
-name = "sausage-actor"
+name = "sausage-interface"
 version = "0.1.0"
 dependencies = [
- "async-channel",
- "serde",
  "serde_json",
- "wstd",
 ]
 
+[[package]]
+name = "sausage-plugin"
+version = "0.1.0"
+dependencies = [
+ "sausage-plugin-macros",
+]
+
+[[package]]
+name = "sausage-plugin-macros"
+version = "0.1.0"
+
+[[package]]
+name = "sausage-vfs"
+version = "0.1.0"
+
 [[package]]
 name = "scopeguard"
 version = "1.2.0"
@@ -1885,7 +1801,7 @@ version = "3.27.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "32497e9a4c7b38532efcdebeef879707aa9f794296a4f0244f6f69e9bc8574bd"
 dependencies = [
- "fastrand 2.5.0",
+ "fastrand",
  "getrandom 0.4.3",
  "once_cell",
  "rustix",
@@ -2156,12 +2072,6 @@ version = "0.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0b928f33d975fc6ad9f86c8f283853ad26bdd5b10b7f1542aa2fa15e2289105a"
 
-[[package]]
-name = "waker-fn"
-version = "1.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "317211a0dc0ceedd78fb2ca9a44aed3d7b9b26f81870d485c07122b4350673b7"
-
 [[package]]
 name = "walkdir"
 version = "2.5.0"
@@ -2187,15 +2097,6 @@ version = "0.11.1+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ccf3ec651a847eb01de73ccad15eb7d99f80485de043efb2f370cd654f4ea44b"
 
-[[package]]
-name = "wasip2"
-version = "1.0.4+wasi-0.2.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b67efb37e106e55ce722a510d6b5f9c17f083e5fc79afc2badeb12cc313d9487"
-dependencies = [
- "wit-bindgen",
-]
-
 [[package]]
 name = "wasm-bindgen"
 version = "0.2.129"
@@ -2926,15 +2827,6 @@ dependencies = [
  "windows-sys 0.59.0",
 ]
 
-[[package]]
-name = "wit-bindgen"
-version = "0.57.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1ebf944e87a7c253233ad6766e082e3cd714b5d03812acc24c318f549614536e"
-dependencies = [
- "bitflags",
-]
-
 [[package]]
 name = "wit-component"
 version = "0.258.3"
@@ -2991,38 +2883,6 @@ version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3ad82d2a33cdc9674dc7465672f271e096168fcdbe0f799d9e6db8c5892679dc"
 
-[[package]]
-name = "wstd"
-version = "0.6.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "29b52936db10a79bb724dadd1c2c3aac958e8229dcb1f1c7f2b7044ca9fc6a3a"
-dependencies = [
- "anyhow",
- "async-task",
- "bytes",
- "futures-lite",
- "http",
- "http-body",
- "http-body-util",
- "itoa",
- "pin-project-lite",
- "serde",
- "serde_json",
- "slab",
- "wasip2",
- "wstd-macro",
-]
-
-[[package]]
-name = "wstd-macro"
-version = "0.6.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "153db9b65508bf6c2efe26617169840c03671ba5719a35868db7682a5261f7d4"
-dependencies = [
- "quote",
- "syn 2.0.119",
-]
-
 [[package]]
 name = "yoke"
 version = "0.8.3"

Cargo.toml

@@ -1,10 +1,11 @@
 [workspace]
 resolver = "3"
-members = ["cli", "agent", "sdk"]
+members = ["cli", "vfs", "interface", "sdk", "sdk/macros"]
 default-members = ["cli"]
-exclude = ["examples"]
+# The agent is rewritten on top of the new SDK. Until then it is not a member.
+exclude = ["examples", "agent"]
 
 # Wasmtime compiles components with Cranelift. Optimize dependencies in dev
-# builds, so that tests and debug runs start actors quickly.
+# builds, so that tests and debug runs start plugins quickly.
 [profile.dev.package."*"]
 opt-level = 2

interface/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "sausage-interface"
+version = "0.1.0"
+edition = "2024"
+description = "Sausage plugin interfaces: OpenRPC documents, the compatibility check, and client code generation."
+
+[dependencies]
+serde_json = "1"

interface/src/compat.rs

@@ -0,0 +1,2 @@
+//! The compatibility check between a consumer's import and a provider's
+//! interface (PROPOSAL.md, section 11.2).

interface/src/lib.rs

@@ -0,0 +1,4 @@
+//! Sausage plugin interfaces: OpenRPC documents, the compatibility check
+//! (`compat`), and the generator of client code for `import!`.
+
+pub mod compat;

sdk/Cargo.toml

@@ -1,15 +1,8 @@
 [package]
-name = "sausage-actor"
+name = "sausage-plugin"
 version = "0.1.0"
 edition = "2024"
-description = "SDK for Sausage actors."
+description = "SDK for Sausage plugins."
-
-[features]
-default = []
-async = ["dep:async-channel", "dep:wstd"]
 
 [dependencies]
-async-channel = { version = "2", optional = true }
+sausage-plugin-macros = { version = "0.1", path = "macros" }
-serde = { version = "1", features = ["derive"] }
-serde_json = "1"
-wstd = { version = "0.6", optional = true }

sdk/macros/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "sausage-plugin-macros"
+version = "0.1.0"
+edition = "2024"
+description = "Macros of the Sausage plugin SDK. Use them through `sausage-plugin`."
+
+[lib]
+proc-macro = true
+
+[dependencies]

sdk/macros/src/lib.rs

@@ -0,0 +1 @@
+//! Macros of the Sausage plugin SDK. Use them through `sausage-plugin`.

sdk/src/lib.rs

@@ -1,229 +1 @@
-//! Small runtime helpers for Sausage actors.
+//! SDK for Sausage plugins.
-
-pub use serde_json::{Value, json};
-
-use serde::{Deserialize, Serialize};
-use std::io::BufRead;
-
-/// A message that an actor receives from the broker.
-#[derive(Clone, Debug, Deserialize, PartialEq, Serialize)]
-pub struct Message {
-    /// The message ID.
-    pub id: String,
-    /// The ID of the sending actor.
-    pub from: String,
-    /// The ID of the message that this message answers.
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub reply_to: Option<String>,
-    /// The message body.
-    pub body: Value,
-}
-
-impl Message {
-    /// Return the body's `type` string, or an empty string when it is missing.
-    pub fn kind(&self) -> &str {
-        self.body["type"].as_str().unwrap_or("")
-    }
-}
-
-fn parse(line: &[u8]) -> Option<Message> {
-    serde_json::from_slice::<Message>(line).ok()
-}
-
-fn is_shutdown(message: &Message) -> bool {
-    message.from == "broker" && message.kind() == "shutdown"
-}
-
-/// Return this actor's ID from `SAUSAGE_ACTOR`, or an empty string if unset.
-pub fn me() -> String {
-    std::env::var("SAUSAGE_ACTOR").unwrap_or_default()
-}
-
-/// Read messages from stdin until EOF or a shutdown message from the broker.
-///
-/// Invalid JSON lines are skipped.
-pub fn messages() -> impl Iterator<Item = Message> {
-    let stdin = std::io::stdin();
-    let mut lines = stdin.lock().lines();
-    std::iter::from_fn(move || {
-        loop {
-            let Ok(line) = lines.next()? else {
-                continue;
-            };
-            let Some(message) = parse(line.as_bytes()) else {
-                continue;
-            };
-            return (!is_shutdown(&message)).then_some(message);
-        }
-    })
-}
-
-/// Send a message to `to` and return its full ID (`<actor>/<own-id>`).
-pub fn send(to: &str, body: Value) -> String {
-    let id = next_id();
-    write_message(json!({"to": to, "id": id, "body": body}));
-    format!("{}/{id}", me())
-}
-
-/// Reply to `message` and return the new message's full ID.
-pub fn reply(message: &Message, body: Value) -> String {
-    let id = next_id();
-    write_message(json!({
-        "to": message.from,
-        "id": id,
-        "reply_to": message.id,
-        "body": body,
-    }));
-    format!("{}/{id}", me())
-}
-
-/// Write a file so that readers see either the old or the new content,
-/// never half of it: write a temporary file next to `path`, then rename it.
-pub fn write_atomic(path: impl AsRef<std::path::Path>, contents: impl AsRef<[u8]>) -> std::io::Result<()> {
-    let path = path.as_ref();
-    let tmp = path.with_file_name(format!(".{}.tmp-{}", path.file_name().unwrap_or_default().to_string_lossy(), next_id()));
-    std::fs::write(&tmp, contents)?;
-    std::fs::rename(&tmp, path)
-}
-
-/// Publish a message to this actor's subscribers and return its full ID.
-pub fn publish(body: Value) -> String {
-    let id = next_id();
-    write_message(json!({"id": id, "body": body}));
-    format!("{}/{id}", me())
-}
-
-fn write_message(message: Value) {
-    use std::io::Write;
-
-    let mut stdout = std::io::stdout().lock();
-    writeln!(stdout, "{message}").unwrap();
-    stdout.flush().unwrap();
-}
-
-fn next_id() -> String {
-    use std::sync::OnceLock;
-    use std::sync::atomic::{AtomicUsize, Ordering};
-    use std::time::{SystemTime, UNIX_EPOCH};
-
-    static START: OnceLock<u128> = OnceLock::new();
-    static SEQUENCE: AtomicUsize = AtomicUsize::new(0);
-    let start = START.get_or_init(|| {
-        SystemTime::now()
-            .duration_since(UNIX_EPOCH)
-            .unwrap_or_default()
-            .as_nanos()
-    });
-    format!("{start}-{}", SEQUENCE.fetch_add(1, Ordering::Relaxed))
-}
-
-/// An asynchronous inbox for actors that use HTTP or timers.
-#[cfg(feature = "async")]
-pub struct Inbox {
-    rx: async_channel::Receiver<Message>,
-    _reader: wstd::runtime::Task<()>,
-}
-
-#[cfg(feature = "async")]
-impl Inbox {
-    /// Start the stdin reader inside the wstd runtime and return its inbox.
-    /// The inbox owns the reader task and must be dropped to cancel it.
-    pub fn start() -> Self {
-        let (tx, rx) = async_channel::unbounded();
-        let reader = wstd::runtime::spawn(read_messages(tx));
-        Self { rx, _reader: reader }
-    }
-
-    /// Wait for the next message, or return `None` at EOF or shutdown.
-    pub async fn recv(&self) -> Option<Message> {
-        self.rx.recv().await.ok()
-    }
-
-    /// Return the next available message without waiting.
-    pub fn try_recv(&self) -> Option<Message> {
-        self.rx.try_recv().ok()
-    }
-
-    /// Return whether the reader closed the inbox, even when messages remain buffered.
-    pub fn is_closed(&self) -> bool {
-        self.rx.is_closed()
-    }
-}
-
-#[cfg(feature = "async")]
-async fn read_messages(tx: async_channel::Sender<Message>) {
-    use wstd::io::AsyncRead;
-
-    let mut stdin = wstd::io::stdin();
-    let mut buf = Vec::new();
-    let mut chunk = [0; 8192];
-    loop {
-        let Ok(n) = stdin.read(&mut chunk).await else {
-            break;
-        };
-        if n == 0 {
-            break;
-        }
-        buf.extend_from_slice(&chunk[..n]);
-        while let Some(pos) = buf.iter().position(|b| *b == b'\n') {
-            let message = parse(&buf[..pos]);
-            buf.drain(..=pos);
-            let Some(message) = message else {
-                continue;
-            };
-            if is_shutdown(&message) {
-                tx.close();
-                return;
-            }
-            if tx.send(message).await.is_err() {
-                return;
-            }
-        }
-    }
-    tx.close();
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn kind_reads_body_type() {
-        let message: Message = serde_json::from_value(json!({
-            "id": "broker/1",
-            "from": "broker",
-            "body": {"type": "ping"}
-        }))
-        .unwrap();
-        assert_eq!(message.kind(), "ping");
-        assert_eq!(message.reply_to, None);
-    }
-
-    #[test]
-    fn kind_is_empty_when_type_is_missing() {
-        let message: Message = serde_json::from_value(json!({
-            "id": "broker/1",
-            "from": "broker",
-            "body": {}
-        }))
-        .unwrap();
-        assert_eq!(message.kind(), "");
-    }
-
-    #[test]
-    fn write_atomic_replaces_the_file() {
-        let dir = std::env::temp_dir().join(format!("sausage-actor-{}", next_id()));
-        std::fs::create_dir_all(&dir).unwrap();
-        let path = dir.join("state.json");
-        write_atomic(&path, "old").unwrap();
-        write_atomic(&path, "new").unwrap();
-        assert_eq!(std::fs::read_to_string(&path).unwrap(), "new");
-        assert_eq!(std::fs::read_dir(&dir).unwrap().count(), 1);
-        std::fs::remove_dir_all(dir).unwrap();
-    }
-
-    #[test]
-    fn generated_ids_differ() {
-        assert_ne!(next_id(), next_id());
-    }
-}

vfs/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "sausage-vfs"
+version = "0.1.0"
+edition = "2024"
+description = "A composable virtual filesystem for WASI guests in Wasmtime."
+
+[dependencies]

vfs/src/lib.rs

@@ -0,0 +1 @@
+//! A composable virtual filesystem for WASI guests in Wasmtime.