STASH to calculate datastore metrics

quickpeep_raker/src/storage.rs

@@ -15,6 +15,7 @@ use ouroboros::self_referencing;
 use reqwest::Url;
 use std::borrow::Cow;
 use std::path::Path;
+use std::sync::atomic::AtomicU64;
 use std::sync::Arc;
 use std::time::{SystemTime, UNIX_EPOCH};
 
@@ -64,6 +65,7 @@ pub struct RakerDb {
 #[derive(Clone)]
 pub struct RakerStore {
     pub mdbx: Arc<RakerDb>,
+    pub metrics: Option<Arc<RakerStoreMetrics>>,
 }
 
 impl RakerStore {
@@ -175,6 +177,14 @@ impl RakerStore {
     }
 }
 
+/// Optional struct to store metrics. Intended for exporting over Prometheus so we can see at a
+/// glance what the shape of the datastore looks like.
+pub struct RakerStoreMetrics {
+    pub active_domains_count: AtomicU64,
+    pub backoff_domains_count: AtomicU64,
+    pub queued_url_count: AtomicU64,
+}
+
 pub struct RakerTxn<'a, K: TransactionKind> {
     pub mdbx_txn: Transaction<'a, K, WriteMap>,
     mdbx: Arc<RakerDb>,
@@ -393,6 +403,10 @@ impl<'a> RakerTxn<'a, RW> {
 
         Ok(true)
     }
+
+    pub fn calculate_initial_metrics(&self) -> anyhow::Result<()> {
+        todo!()
+    }
 }
 
 /// Read-only implementations (but can also be used on RW transactions)