Host: one place for the instance config; message ids are strings

PROTOCOL.md

@@ -37,7 +37,7 @@ A line on **stdout**:
   Text for people is `{"type": "text", "text": "..."}`.
 - `to` is the recipient. Without `to`, the broker publishes the message to
   every subscriber of the sender.
-- `id` is optional. If the actor sets it, the message ID is `"<sender>/<id>"`.
+- `id` is an optional string. If the actor sets it, the message ID is `"<sender>/<id>"`.
   Otherwise, the broker assigns `m-<n>`. The broker always sets `from`.
 - `reply_to` marks a reply: its value is the ID of the message it answers.
   There is no request/response. A reply is a new message.

cli/src/broker.rs

@@ -19,7 +19,7 @@ use wasmtime::component::Component;
 
 use crate::candidate;
 use crate::fs::Mount;
-use crate::runtime::Runtime;
+use crate::runtime::{InstanceConfig, Runtime};
 use crate::supervisor::{Control, Reply, Supervisor};
 use crate::world::{self, ActorMeta, NATIVE, VersionMeta, World};
 
@@ -139,14 +139,10 @@ impl Broker {
             self.log(from, &format!("message without \"body\", ignored: {}", truncate(line, 500)));
             return;
         };
-        let own_id = match obj.get("id") {
+        let own_id = obj.get("id").and_then(Value::as_str);
-            Some(Value::String(s)) => Some(s.clone()),
-            Some(Value::Number(n)) => Some(n.to_string()),
-            _ => None,
-        };
         let to = obj.get("to").and_then(Value::as_str);
         let reply_to = obj.get("reply_to").and_then(Value::as_str);
-        self.send(from, to, own_id.as_deref(), reply_to, body);
+        self.send(from, to, own_id, reply_to, body);
     }
 
     fn deliver(&self, env: Envelope) {
@@ -178,13 +174,25 @@ impl Broker {
         self.op_locks.lock().unwrap().entry(id.to_string()).or_default().clone()
     }
 
-    /// Mounts of a running actor. `/actor` hides every `data/` folder.
+    /// What an instance of `id` gets (see PROTOCOL.md). A candidate runs in
-    pub fn mounts(&self, id: &str) -> Vec<Mount> {
+    /// `scratch`, which holds a copy of the actor's `data/` and `public/`,
-        vec![
+    /// and has no HTTP.
-            Mount { guest: "/actor".into(), host: self.world.actors_root(), writable: false },
+    pub fn instance_config(&self, id: &str, version: u64, scratch: Option<&Path>) -> InstanceConfig {
-            Mount { guest: "/public".into(), host: self.world.public_dir(id), writable: true },
+        let own = scratch.map_or_else(|| self.world.actor_dir(id), Path::to_path_buf);
-            Mount { guest: "/data".into(), host: self.world.data_dir(id), writable: true },
+        let mut env = vec![("SAUSAGE_ACTOR".into(), id.to_string()), ("SAUSAGE_VERSION".into(), version.to_string())];
-        ]
+        if scratch.is_some() {
+            env.push(("SAUSAGE_CANDIDATE".into(), "1".into()));
+        }
+        InstanceConfig {
+            mounts: vec![
+                Mount { guest: "/actor".into(), host: self.world.actors_root(), writable: false },
+                Mount { guest: "/public".into(), host: own.join("public"), writable: true },
+                Mount { guest: "/data".into(), host: own.join("data"), writable: true },
+            ],
+            allow_http: scratch.is_none(),
+            stderr_log: own.join("stderr.log"),
+            env,
+        }
     }
 
     // ---------------------------------------------------------------------

cli/src/candidate.rs

@@ -29,8 +29,7 @@ use serde_json::{Value, json};
 use wasmtime::component::Component;
 
 use crate::broker::{Broker, SHUTDOWN_DEADLINE, shutdown_line, truncate};
-use crate::fs::Mount;
+use crate::runtime::Instance;
-use crate::runtime::{Instance, InstanceConfig};
 use crate::world;
 
 const EXPECT_TIMEOUT: Duration = Duration::from_secs(10);
@@ -104,20 +103,7 @@ impl Candidate<'_> {
                 world::copy_tree(&from, &dir.join(name))?;
             }
         }
-        let cfg = InstanceConfig {
+        let cfg = self.broker.instance_config(self.id, self.version, Some(&dir));
-            mounts: vec![
-                Mount { guest: "/actor".into(), host: self.broker.world.actors_root(), writable: false },
-                Mount { guest: "/public".into(), host: dir.join("public"), writable: true },
-                Mount { guest: "/data".into(), host: dir.join("data"), writable: true },
-            ],
-            allow_http: false,
-            stderr_log: dir.join("stderr.log"),
-            env: vec![
-                ("SAUSAGE_ACTOR".into(), self.id.to_string()),
-                ("SAUSAGE_VERSION".into(), self.version.to_string()),
-                ("SAUSAGE_CANDIDATE".into(), "1".into()),
-            ],
-        };
         Ok((self.broker.runtime.start(self.component, cfg)?, scratch))
     }
 

cli/src/supervisor.rs

@@ -12,7 +12,7 @@ use tokio::sync::{mpsc, oneshot};
 use wasmtime::component::Component;
 
 use crate::broker::{Broker, Envelope, SHUTDOWN_DEADLINE, shutdown_line};
-use crate::runtime::{Exit, Instance, InstanceConfig};
+use crate::runtime::{Exit, Instance};
 
 /// A new version that crashes this often within `CRASH_WINDOW` after an
 /// upgrade is rolled back automatically.
@@ -178,16 +178,7 @@ impl Supervisor {
         if self.component.is_none() {
             self.component = Some(self.broker.load_version(&self.id, self.version)?);
         }
-        let world = &self.broker.world;
+        let cfg = self.broker.instance_config(&self.id, self.version, None);
-        let cfg = InstanceConfig {
-            mounts: self.broker.mounts(&self.id),
-            allow_http: true,
-            stderr_log: world.actor_dir(&self.id).join("stderr.log"),
-            env: vec![
-                ("SAUSAGE_ACTOR".into(), self.id.clone()),
-                ("SAUSAGE_VERSION".into(), self.version.to_string()),
-            ],
-        };
         self.instance = Some(self.broker.runtime.start(self.component.as_ref().unwrap(), cfg)?);
         Ok(())
     }