Add cache_clear operation

Author: 9999years

src/lib.rs

@@ -445,6 +445,13 @@ pub trait IOCached<K, V> {
     /// Should return `Self::Error` if the operation fails
     fn cache_remove(&self, k: &K) -> Result<Option<V>, Self::Error>;
 
+    /// Remove all cached values
+    ///
+    /// # Errors
+    ///
+    /// Should return `Self::Error` if the operation fails
+    fn cache_clear(&self) -> Result<(), Self::Error>;
+
     /// Set the flag to control whether cache hits refresh the ttl of cached values, returns the old flag value
     fn cache_set_refresh(&mut self, refresh: bool) -> bool;
 
@@ -479,6 +486,9 @@ pub trait IOCachedAsync<K, V> {
     /// Remove a cached value
     async fn cache_remove(&self, k: &K) -> Result<Option<V>, Self::Error>;
 
+    /// Remove all cached values
+    async fn cache_clear(&self) -> Result<(), Self::Error>;
+
     /// Set the flag to control whether cache hits refresh the ttl of cached values, returns the old flag value
     fn cache_set_refresh(&mut self, refresh: bool) -> bool;
 

src/stores/disk.rs

@@ -353,6 +353,13 @@ where
         self.ttl
     }
 
+    fn cache_clear(&self) -> Result<(), Self::Error> {
+        for (key, value) in self.connection.iter().flatten() {
+            self.connection.remove(key)?;
+        }
+        Ok(())
+    }
+
     fn cache_set_lifespan(&mut self, ttl: Duration) -> Option<Duration> {
         let old = self.ttl;
         self.ttl = Some(ttl);

src/stores/redis.rs

@@ -1,4 +1,5 @@
 use crate::IOCached;
+use redis::Commands;
 use serde::de::DeserializeOwned;
 use serde::Serialize;
 use std::marker::PhantomData;
@@ -217,7 +218,7 @@ where
         RedisCacheBuilder::new(prefix, ttl)
     }
 
-    fn generate_key(&self, key: &K) -> String {
+    fn generate_key(&self, key: impl Display) -> String {
         format!("{}{}{}", self.namespace, self.prefix, key)
     }
 
@@ -345,6 +346,19 @@ where
         Some(self.ttl)
     }
 
+    fn cache_clear(&self) -> Result<(), Self::Error> {
+        // `scan_match` takes `&mut self`, so we need two connection objects to scan and
+        // delete...?
+        let mut scan = self.pool.get()?;
+        let mut delete = self.pool.get()?;
+
+        for key in scan.scan_match::<_, String>(self.generate_key("*"))? {
+            delete.del(key)?;
+        }
+
+        Ok(())
+    }
+
     fn cache_set_lifespan(&mut self, ttl: Duration) -> Option<Duration> {
         let old = self.ttl;
         self.ttl = ttl;
@@ -628,6 +642,15 @@ mod async_redis {
             }
         }
 
+        async fn cache_clear(&self) -> Result<(), Self::Error> {
+            let mut conn = self.connection.clone();
+
+            // https://redis.io/commands/flushdb/
+            let _: () = redis::cmd("FLUSHDB").query_async(&mut conn).await?;
+
+            Ok(())
+        }
+
         /// Set the flag to control whether cache hits refresh the ttl of cached values, returns the old flag value
         fn cache_set_refresh(&mut self, refresh: bool) -> bool {
             let old = self.refresh;