fix(sql): minimize deadlock potential between acking and enqueueing (#62

)

keiko-sql/src/main/kotlin/com/netflix/spinnaker/q/sql/SqlQueue.kt

@@ -626,26 +626,30 @@ class SqlQueue(
   }
 
   private fun ackMessage(fingerprint: String) {
+    /* TODO: since this isn't transactional, we should periodically check for and cleanup
+     *  any old messages with fingerprints not represented on the queue or in unacked.
+     */
     withRetry(RetryCategory.WRITE) {
-      jooq.transaction { config ->
-        val txn = DSL.using(config)
+      jooq.deleteFrom(unackedTable)
+        .where(fingerprintField.eq(fingerprint))
+        .execute()
+    }
 
-        txn.deleteFrom(unackedTable)
-          .where(fingerprintField.eq(fingerprint))
-          .execute()
+    val changed = withRetry(RetryCategory.WRITE) {
+      jooq.update(queueTable)
+        .set(lockedField, "0")
+        .where(fingerprintField.eq(fingerprint))
+        .execute()
+    }
 
-        val changed = txn.update(queueTable)
-          .set(lockedField, "0")
+    if (changed == 0) {
+      withRetry(RetryCategory.WRITE) {
+        jooq.deleteFrom(messagesTable)
           .where(fingerprintField.eq(fingerprint))
           .execute()
-
-        if (changed == 0) {
-          txn.deleteFrom(messagesTable)
-            .where(fingerprintField.eq(fingerprint))
-            .execute()
-        }
       }
     }
+
     fire(MessageAcknowledged)
   }