proxy finalized, use it by setting 'lmdb-with-metrics'

src/db/lmdb_adapter.rs

@@ -39,12 +39,15 @@ pub struct LmdbDb {
 }
 
 impl LmdbDb {
-	pub fn init(db: Env) -> Db {
+	pub fn to_wrap(db: Env) -> Self {
-		let s = Self {
+		Self {
 			db,
 			trees: RwLock::new((Vec::new(), HashMap::new())),
-		};
+		}
-		Db(Arc::new(s))
+	}
+
+	pub fn init(db: Env) -> Db {
+		Db(Arc::new(Self::to_wrap(db)))
 	}
 
 	fn get_tree(&self, i: usize) -> Result<Database> {

src/db/metric_proxy.rs

@@ -1,8 +1,12 @@
 use std::path::PathBuf;
+use std::sync::Arc;
 use std::time::Instant;
 
-use crate::lmdb_adapter::{LmdbDb, LmdbTx};
+use crate::lmdb_adapter::LmdbDb;
-use crate::{Bound, IDb, ITx, ITxFn, OnCommit, Result, TxResult, Value, ValueIter};
+use crate::{
+	Bound, Db, IDb, ITx, ITxFn, OnCommit, Result, TxFnResult, TxOpResult, TxResult, TxValueIter,
+	Value, ValueIter,
+};
 use opentelemetry::{
 	global,
 	metrics::{Counter, ValueRecorder},
@@ -10,15 +14,16 @@ use opentelemetry::{
 };
 
 pub struct MetricDbProxy {
+	//@FIXME Replace with a template
 	db: LmdbDb,
 	op_counter: Counter<u64>,
 	op_duration: ValueRecorder<f64>,
 }
 
 impl MetricDbProxy {
-	pub fn init(db: LmdbDb) -> MetricDbProxy {
+	pub fn init(db: LmdbDb) -> Db {
 		let meter = global::meter("garage/web");
-		Self {
+		let s = Self {
 			db,
 			op_counter: meter
 				.u64_counter("db.op_counter")
@@ -28,7 +33,8 @@ impl MetricDbProxy {
 				.f64_value_recorder("db.op_duration")
 				.with_description("Duration of operations on the local metadata engine")
 				.init(),
-		}
+		};
+		Db(Arc::new(s))
 	}
 
 	fn instrument<T>(
@@ -131,10 +137,87 @@ impl IDb for MetricDbProxy {
 	// ----
 
 	fn transaction(&self, f: &dyn ITxFn) -> TxResult<OnCommit, ()> {
-		self.instrument(|| self.db.transaction(f), "transaction", "control", "yes")
+		self.instrument(
+			|| self.db.transaction(&MetricITxFnProxy { f, metrics: self }),
+			"transaction",
+			"control",
+			"yes",
+		)
+	}
+}
+
+struct MetricITxFnProxy<'a> {
+	f: &'a dyn ITxFn,
+	metrics: &'a MetricDbProxy,
+}
+impl<'a> ITxFn for MetricITxFnProxy<'a> {
+	fn try_on(&self, tx: &mut dyn ITx) -> TxFnResult {
+		self.f.try_on(&mut MetricTxProxy {
+			tx,
+			metrics: self.metrics,
+		})
 	}
 }
 
 struct MetricTxProxy<'a> {
-	tx: LmdbTx<'a>,
+	tx: &'a mut dyn ITx,
+	metrics: &'a MetricDbProxy,
+}
+impl<'a> ITx for MetricTxProxy<'a> {
+	fn get(&self, tree: usize, key: &[u8]) -> TxOpResult<Option<Value>> {
+		self.metrics
+			.instrument(|| self.tx.get(tree, key), "get", "data", "yes")
+	}
+
+	fn len(&self, tree: usize) -> TxOpResult<usize> {
+		self.metrics
+			.instrument(|| self.tx.len(tree), "len", "data", "yes")
+	}
+
+	fn insert(&mut self, tree: usize, key: &[u8], value: &[u8]) -> TxOpResult<Option<Value>> {
+		self.metrics
+			.instrument(|| self.tx.insert(tree, key, value), "insert", "data", "yes")
+	}
+
+	fn remove(&mut self, tree: usize, key: &[u8]) -> TxOpResult<Option<Value>> {
+		self.metrics
+			.instrument(|| self.tx.remove(tree, key), "remove", "data", "yes")
+	}
+
+	fn clear(&mut self, tree: usize) -> TxOpResult<()> {
+		self.metrics
+			.instrument(|| self.tx.clear(tree), "clear", "data", "yes")
+	}
+
+	fn iter(&self, tree: usize) -> TxOpResult<TxValueIter<'_>> {
+		self.metrics
+			.instrument(|| self.tx.iter(tree), "iter", "data", "yes")
+	}
+	fn iter_rev(&self, tree: usize) -> TxOpResult<TxValueIter<'_>> {
+		self.metrics
+			.instrument(|| self.tx.iter_rev(tree), "iter_rev", "data", "yes")
+	}
+	fn range<'r>(
+		&self,
+		tree: usize,
+		low: Bound<&'r [u8]>,
+		high: Bound<&'r [u8]>,
+	) -> TxOpResult<TxValueIter<'_>> {
+		self.metrics
+			.instrument(|| self.tx.range(tree, low, high), "range", "data", "yes")
+	}
+
+	fn range_rev<'r>(
+		&self,
+		tree: usize,
+		low: Bound<&'r [u8]>,
+		high: Bound<&'r [u8]>,
+	) -> TxOpResult<TxValueIter<'_>> {
+		self.metrics.instrument(
+			|| self.tx.range_rev(tree, low, high),
+			"range_rev",
+			"data",
+			"yes",
+		)
+	}
 }

src/db/open.rs

@@ -10,6 +10,7 @@ use crate::{Db, Error, Result};
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub enum Engine {
 	Lmdb,
+	LmdbWithMetrics,
 	Sqlite,
 }
 
@@ -18,6 +19,7 @@ impl Engine {
 	pub fn as_str(&self) -> &'static str {
 		match self {
 			Self::Lmdb => "lmdb",
+			Self::LmdbWithMetrics => "lmdb-with-metrics",
 			Self::Sqlite => "sqlite",
 		}
 	}
@@ -35,6 +37,7 @@ impl std::str::FromStr for Engine {
 	fn from_str(text: &str) -> Result<Engine> {
 		match text {
 			"lmdb" | "heed" => Ok(Self::Lmdb),
+			"lmdb-with-metrics" | "heed-with-metrics" => Ok(Self::LmdbWithMetrics),
 			"sqlite" | "sqlite3" | "rusqlite" => Ok(Self::Sqlite),
 			"sled" => Err(Error("Sled is no longer supported as a database engine. Converting your old metadata db can be done using an older Garage binary (e.g. v0.9.4).".into())),
 			kind => Err(Error(
@@ -74,7 +77,7 @@ pub fn open_db(path: &PathBuf, engine: Engine, opt: &OpenOpt) -> Result<Db> {
 
 		// ---- LMDB DB ----
 		#[cfg(feature = "lmdb")]
-		Engine::Lmdb => {
+		Engine::Lmdb | Engine::LmdbWithMetrics => {
 			info!("Opening LMDB database at: {}", path.display());
 			if let Err(e) = std::fs::create_dir_all(&path) {
 				return Err(Error(
@@ -109,7 +112,13 @@ pub fn open_db(path: &PathBuf, engine: Engine, opt: &OpenOpt) -> Result<Db> {
 					))
 				}
 				Err(e) => Err(Error(format!("Cannot open LMDB database: {}", e).into())),
-				Ok(db) => Ok(crate::lmdb_adapter::LmdbDb::init(db)),
+				Ok(db) => match engine {
+					Engine::LmdbWithMetrics => {
+						let to_wrap = crate::lmdb_adapter::LmdbDb::to_wrap(db);
+						Ok(crate::metric_proxy::MetricDbProxy::init(to_wrap))
+					}
+					_ => Ok(crate::lmdb_adapter::LmdbDb::init(db)),
+				},
 			}
 		}
 

src/model/garage.rs

@@ -121,7 +121,7 @@ impl Garage {
 			db::Engine::Sqlite => {
 				db_path.push("db.sqlite");
 			}
-			db::Engine::Lmdb => {
+			db::Engine::Lmdb | db::Engine::LmdbWithMetrics => {
 				db_path.push("db.lmdb");
 			}
 		}