an agent gets one todo when its pr starts conflicting with the target branch

swarm-controller/src/forge_events.rs

@@ -10,6 +10,9 @@
 //! `pull_request_sync`, …), not `X-Forgejo-Event`, which folds those into
 //! `issues` and `pull_request`. It reaches the subject only once it is one
 //! plain token.
+//!
+//! [`publish_event`] keeps an event this daemon makes, such as the
+//! `pull_request_mergeability` event of `crate::pr_conflicts`, the same way.
 
 use axum::http::HeaderMap;
 use std::time::Duration;
@@ -51,15 +54,42 @@ pub(crate) async fn publish(
     body: axum::body::Bytes,
 ) -> Result<(), NotKept> {
     let subject = subject(headers)?;
+    let mut message = async_nats::jetstream::message::PublishMessage::build().payload(body);
+    if let Some(id) = headers.get(DELIVERY_HEADER).and_then(|v| v.to_str().ok()) {
+        message = message.message_id(id);
+    }
+    keep(state, subject, message).await
+}
+
+/// Keep an event this daemon makes itself, of `event_type`, in the stream, and
+/// wait for the stream's ack. The router reads it like a delivery.
+pub(crate) async fn publish_event(
+    state: &crate::routes::AppState,
+    event_type: &str,
+    body: Vec<u8>,
+) -> Result<(), NotKept> {
+    if !swarm_wire::forge_events::is_subject_token(event_type) {
+        return Err(NotKept::BadEventType);
+    }
+    let message = async_nats::jetstream::message::PublishMessage::build().payload(body.into());
+    keep(
+        state,
+        swarm_wire::forge_events::subject(event_type),
+        message,
+    )
+    .await
+}
+
+async fn keep(
+    state: &crate::routes::AppState,
+    subject: String,
+    message: async_nats::jetstream::message::PublishMessage,
+) -> Result<(), NotKept> {
     let Some(status) = state.status.as_ref() else {
         return Err(NotKept::Queue("no swarm queue is configured".to_owned()));
     };
     let client = status.queue_client();
     swarm_queue_client::ensure_connected(&client).map_err(|e| NotKept::Queue(e.to_string()))?;
-    let mut message = async_nats::jetstream::message::PublishMessage::build().payload(body);
-    if let Some(id) = headers.get(DELIVERY_HEADER).and_then(|v| v.to_str().ok()) {
-        message = message.message_id(id);
-    }
     let kept = async {
         swarm_queue_client::forge_events::open_or_create(&client)
             .await