delivery_metrics: DRY and encapsulate better

Make it more difficult to misuse and less boilerplate to use

crates/kumod/src/delivery_metrics.rs

@@ -2,21 +2,21 @@ use prometheus::{IntCounter, IntGauge};
 
 #[derive(Clone, Debug)]
 pub struct DeliveryMetrics {
-    pub connection_gauge: IntGauge,
-    pub global_connection_gauge: IntGauge,
-    pub connection_total: IntCounter,
-    pub global_connection_total: IntCounter,
+    connection_gauge: IntGauge,
+    global_connection_gauge: IntGauge,
+    connection_total: IntCounter,
+    global_connection_total: IntCounter,
 
     pub ready_count: IntGauge,
 
-    pub msgs_delivered: IntCounter,
-    pub global_msgs_delivered: IntCounter,
+    msgs_delivered: IntCounter,
+    global_msgs_delivered: IntCounter,
 
-    pub msgs_transfail: IntCounter,
-    pub global_msgs_transfail: IntCounter,
+    msgs_transfail: IntCounter,
+    global_msgs_transfail: IntCounter,
 
-    pub msgs_fail: IntCounter,
-    pub global_msgs_fail: IntCounter,
+    msgs_fail: IntCounter,
+    global_msgs_fail: IntCounter,
 }
 
 impl DeliveryMetrics {
@@ -55,6 +55,31 @@ impl DeliveryMetrics {
             global_msgs_fail: crate::metrics_helper::total_msgs_fail_for_service(service_type),
         }
     }
+
+    pub fn inc_transfail(&self) {
+        self.msgs_transfail.inc();
+        self.global_msgs_transfail.inc();
+    }
+
+    pub fn inc_transfail_by(&self, amount: usize) {
+        self.msgs_transfail.inc_by(amount as u64);
+        self.global_msgs_transfail.inc_by(amount as u64);
+    }
+
+    pub fn inc_fail(&self) {
+        self.msgs_fail.inc();
+        self.global_msgs_fail.inc();
+    }
+
+    pub fn inc_fail_by(&self, amount: usize) {
+        self.msgs_fail.inc_by(amount as u64);
+        self.global_msgs_fail.inc_by(amount as u64);
+    }
+
+    pub fn inc_delivered(&self) {
+        self.msgs_delivered.inc();
+        self.global_msgs_delivered.inc();
+    }
 }
 
 /// A helper struct to manage the number of connections.

crates/kumod/src/lua_deliver.rs

@@ -136,11 +136,9 @@ impl QueueDispatcher for LuaQueueDispatcher {
                             })
                             .await?;
                         }
-                        dispatcher.metrics.msgs_transfail.inc();
-                        dispatcher.metrics.global_msgs_transfail.inc();
+                        dispatcher.metrics.inc_transfail();
                     } else {
-                        dispatcher.metrics.msgs_fail.inc();
-                        dispatcher.metrics.global_msgs_fail.inc();
+                        dispatcher.metrics.inc_fail();
                         tracing::debug!(
                             "failed to send message to {}: {response:?}",
                             dispatcher.name,
@@ -195,8 +193,7 @@ impl QueueDispatcher for LuaQueueDispatcher {
                         SpoolManager::remove_from_spool(*msg.id()).await
                     })?;
                 }
-                dispatcher.metrics.msgs_delivered.inc();
-                dispatcher.metrics.global_msgs_delivered.inc();
+                dispatcher.metrics.inc_delivered();
             }
         }
 

crates/kumod/src/ready_queue.rs

@@ -516,8 +516,7 @@ impl Dispatcher {
                         })
                         .await;
                         Dispatcher::requeue_message(msg, true, None).await?;
-                        dispatcher.metrics.msgs_transfail.inc();
-                        dispatcher.metrics.global_msgs_transfail.inc();
+                        dispatcher.metrics.inc_transfail();
                     }
 
                     if consecutive_connection_failures.fetch_add(1, Ordering::SeqCst)
@@ -725,11 +724,9 @@ impl Dispatcher {
             let egress_pool = self.egress_pool.clone();
             let egress_source = self.egress_source.name.clone();
             if response.is_transient() {
-                self.metrics.msgs_transfail.inc_by(msgs.len() as u64);
-                self.metrics.global_msgs_transfail.inc_by(msgs.len() as u64);
+                self.metrics.inc_transfail_by(msgs.len());
             } else {
-                self.metrics.msgs_fail.inc_by(msgs.len() as u64);
-                self.metrics.global_msgs_fail.inc_by(msgs.len() as u64);
+                self.metrics.inc_fail_by(msgs.len());
             }
             rt_spawn(
                 format!("bulk queue op for {} msgs {name} {response:?}", msgs.len()),

crates/kumod/src/smtp_dispatcher.rs

@@ -377,12 +377,10 @@ impl QueueDispatcher for SmtpDispatcher {
                     })
                     .await?;
                 }
-                dispatcher.metrics.msgs_transfail.inc();
-                dispatcher.metrics.global_msgs_transfail.inc();
+                dispatcher.metrics.inc_transfail();
             }
             Err(ClientError::Rejected(response)) => {
-                dispatcher.metrics.msgs_fail.inc();
-                dispatcher.metrics.global_msgs_fail.inc();
+                dispatcher.metrics.inc_fail();
                 tracing::debug!(
                     "failed to send message to {} {:?}: {response:?}",
                     dispatcher.name,
@@ -434,8 +432,7 @@ impl QueueDispatcher for SmtpDispatcher {
                         SpoolManager::remove_from_spool(*msg.id()).await
                     })?;
                 }
-                dispatcher.metrics.msgs_delivered.inc();
-                dispatcher.metrics.global_msgs_delivered.inc();
+                dispatcher.metrics.inc_delivered();
             }
         };