gardesk/garwarp / c35eb64

Browse files

make terminal transitions idempotent

Authored by mfwolffe <wolffemf@dukes.jmu.edu>
SHA
c35eb649243aa9b8580c6b793482f6e470c79a9f
Parents
13125f4
Tree
d1f544f

2 changed files

StatusFile+-
M garwarp/src/daemon.rs 47 0
M garwarp/src/request.rs 27 0
garwarp/src/daemon.rsmodified
@@ -542,6 +542,53 @@ mod tests {
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         assert_eq!(state.requests.state("req-1"), Some(RequestState::Pending));
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     }
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+    #[test]
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+    fn duplicate_cancel_returns_ack() {
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+        let (mut client, server) = UnixStream::pair().expect("pair should be created");
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+        client
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+            .write_all(b"transition id=req-1 sender=:1.2 state=cancelled\n")
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+            .expect("transition request should be written");
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+
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+        let mut state = DaemonState {
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+            health: HealthStatus::Healthy,
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+            requests: RequestRegistry::new(Duration::from_secs(5)),
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+            running: true,
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+        };
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+        state
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+            .requests
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+            .begin_at(
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+                "req-1",
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+                RequestOwner::new(":1.2", None),
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+                None,
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+                Instant::now(),
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+            )
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+            .expect("request should be created");
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+        state
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+            .requests
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+            .transition(
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+                "req-1",
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+                &RequestOwner::new(":1.2", None),
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+                RequestState::Cancelled,
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+            )
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+            .expect("first cancel should transition");
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+        handle_connection(server, &mut state).expect("transition should be handled");
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+
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+        let mut response_line = String::new();
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+        let mut reader = BufReader::new(client);
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+        reader
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+            .read_line(&mut response_line)
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+            .expect("response should be readable");
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+        let response = ControlResponse::parse_line(&response_line).expect("response should parse");
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+        assert_eq!(
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+            response,
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+            ControlResponse::AckRequest {
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+                id: "req-1".to_string(),
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+                state: "cancelled".to_string(),
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+            }
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+        );
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+        assert_eq!(state.requests.state("req-1"), Some(RequestState::Cancelled));
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+    }
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+
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     #[test]
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     fn startup_recovery_expires_non_terminal_requests() {
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         let path = unique_temp_file();
garwarp/src/request.rsmodified
@@ -191,6 +191,11 @@ impl RequestRegistry {
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             return Err(RequestError::OwnerMismatch(id.to_string()));
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         }
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+        if entry.state == target && target.is_terminal() {
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+            entry.last_updated_at = now;
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+            return Ok(());
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+        }
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+
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         if !is_valid_transition(entry.state, target) {
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             return Err(RequestError::InvalidTransition {
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                 id: id.to_string(),
@@ -546,4 +551,26 @@ mod tests {
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         assert!(removed.is_empty());
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         assert_eq!(registry.state("req-1"), Some(RequestState::Pending));
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     }
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+
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+    #[test]
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+    fn duplicate_cancel_is_idempotent() {
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+        let now = Instant::now();
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+        let request_owner = owner(":1.2");
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+        let mut registry = RequestRegistry::new(Duration::from_secs(5));
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+        registry
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+            .begin_at("req-1", request_owner.clone(), None, now)
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+            .expect("request should be created");
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+        registry
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+            .transition_at("req-1", &request_owner, RequestState::Cancelled, now)
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+            .expect("first cancel should succeed");
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+        registry
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+            .transition_at(
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+                "req-1",
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+                &request_owner,
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+                RequestState::Cancelled,
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+                now + Duration::from_millis(50),
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+            )
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+            .expect("duplicate cancel should be idempotent");
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+        assert_eq!(registry.state("req-1"), Some(RequestState::Cancelled));
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+    }
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 }