add: redis cache support

crates/core/src/cache/mod.rs

@@ -0,0 +1,77 @@
+#![allow(async_fn_in_trait)]
+use serde::{Serialize, de::DeserializeOwned};
+
+pub const EXPIRE_AT: i64 = 3_600_000;
+
+#[allow(type_alias_bounds)]
+pub type TimedObject<T: Serialize + DeserializeOwned> = (i64, T);
+
+#[cfg(feature = "redis")]
+pub mod redis;
+
+#[cfg(not(feature = "redis"))]
+pub mod no_cache;
+
+/// A simple cache "database".
+pub trait Cache {
+    type Item;
+    type Client;
+
+    /// Create a new [`Cache`].
+    async fn new() -> Self;
+    /// Get a connection to the cache.
+    async fn get_con(&self) -> Self::Client;
+
+    /// Get a cache object by its identifier
+    ///
+    /// # Arguments
+    /// * `id` - `String` of the object's id
+    async fn get(&self, id: Self::Item) -> Option<String>;
+    /// Set a cache object by its identifier and content
+    ///
+    /// # Arguments
+    /// * `id` - `String` of the object's id
+    /// * `content` - `String` of the object's content
+    async fn set(&self, id: Self::Item, content: Self::Item) -> bool;
+    /// Update a cache object by its identifier and content
+    ///
+    /// # Arguments
+    /// * `id` - `String` of the object's id
+    /// * `content` - `String` of the object's content
+    async fn update(&self, id: Self::Item, content: Self::Item) -> bool;
+    /// Remove a cache object by its identifier
+    ///
+    /// # Arguments
+    /// * `id` - `String` of the object's id
+    async fn remove(&self, id: Self::Item) -> bool;
+    /// Remove a cache object by its identifier('s start)
+    ///
+    /// # Arguments
+    /// * `id` - `String` of the object's id('s start)
+    async fn remove_starting_with(&self, id: Self::Item) -> bool;
+    /// Increment a cache object by its identifier
+    ///
+    /// # Arguments
+    /// * `id` - `String` of the object's id
+    async fn incr(&self, id: Self::Item) -> bool;
+    /// Decrement a cache object by its identifier
+    ///
+    /// # Arguments
+    /// * `id` - `String` of the object's id
+    async fn decr(&self, id: Self::Item) -> bool;
+
+    /// Get a cache object by its identifier
+    ///
+    /// # Arguments
+    /// * `id` - `String` of the object's id
+    async fn get_timed<T: Serialize + DeserializeOwned>(
+        &self,
+        id: Self::Item,
+    ) -> Option<TimedObject<T>>;
+    /// Set a cache object by its identifier and content
+    ///
+    /// # Arguments
+    /// * `id` - `String` of the object's id
+    /// * `content` - `String` of the object's content
+    async fn set_timed<T: Serialize + DeserializeOwned>(&self, id: Self::Item, content: T) -> bool;
+}