database: introduce read_feed_with_cursor

read_feed_with_cursor allows using an arbitrary string as a cursor,
unlike read_feed_with_limit, which uses last post's UID as a cursor.

3 files changed, 32 insertions, 3 deletions

diff --git a/kittybox-rs/src/database/file/mod.rs b/kittybox-rs/src/database/file/mod.rs
index 531f7b1..a9de63e 100644
--- a/kittybox-rs/src/database/file/mod.rs
+++ b/kittybox-rs/src/database/file/mod.rs
@@ -499,6 +499,16 @@ impl Storage for FileStorage {
         }
     }
 
+    async fn read_feed_with_cursor(
+        &self,
+        url: &'_ str,
+        cursor: Option<&'_ str>,
+        limit: usize,
+        user: Option<&'_ str>
+    ) -> Result<Option<(serde_json::Value, Option<String>)>> {
+        todo!()
+    }
+
     #[tracing::instrument(skip(self))]
     async fn read_feed_with_limit(
         &self,
@@ -605,7 +615,7 @@ impl Storage for FileStorage {
     }
 
     #[tracing::instrument(skip(self))]
-    async fn set_setting<S: settings::Setting<'a>, 'a>(&self, user: &'_ str, value: S::Data) -> Result<()> {
+    async fn set_setting<S: settings::Setting<'a> + 'a, 'a>(&self, user: &'a str, value: S::Data) -> Result<()> {
         let url = axum::http::Uri::try_from(user).expect("Couldn't parse a URL");
         let mut path = relative_path::RelativePathBuf::new();
         path.push(url.authority().unwrap().to_string());
diff --git a/kittybox-rs/src/database/memory.rs b/kittybox-rs/src/database/memory.rs
index 9d79ecc..36e924f 100644
--- a/kittybox-rs/src/database/memory.rs
+++ b/kittybox-rs/src/database/memory.rs
@@ -238,6 +238,17 @@ impl Storage for MemoryStorage {
         todo!()
     }
 
+    #[allow(unused_variables)]
+    async fn read_feed_with_cursor(
+        &self,
+        url: &'_ str,
+        cursor: Option<&'_ str>,
+        limit: usize,
+        user: Option<&'_ str>
+    ) -> Result<Option<(serde_json::Value, Option<String>)>> {
+        todo!()
+    }
+
     async fn delete_post(&self, url: &'_ str) -> Result<()> {
         self.mapping.write().await.remove(url);
         Ok(())
@@ -249,7 +260,7 @@ impl Storage for MemoryStorage {
     }
 
     #[allow(unused_variables)]
-    async fn set_setting<S: settings::Setting<'a>, 'a>(&self, user: &'_ str, value: S::Data) -> Result<()> {
+    async fn set_setting<S: settings::Setting<'a> + 'a, 'a>(&self, user: &'a str, value: S::Data) -> Result<()> {
         todo!()
     }
 
diff --git a/kittybox-rs/src/database/mod.rs b/kittybox-rs/src/database/mod.rs
index ea4205c..4b1b348 100644
--- a/kittybox-rs/src/database/mod.rs
+++ b/kittybox-rs/src/database/mod.rs
@@ -330,6 +330,14 @@ pub trait Storage: std::fmt::Debug + Clone + Send + Sync {
         user: &'_ Option<String>,
     ) -> Result<Option<serde_json::Value>>;
 
+    async fn read_feed_with_cursor(
+        &self,
+        url: &'_ str,
+        cursor: Option<&'_ str>,
+        limit: usize,
+        user: Option<&'_ str>
+    ) -> Result<Option<(serde_json::Value, Option<String>)>>;
+
     /// Deletes a post from the database irreversibly. 'nuff said. Must be idempotent.
     async fn delete_post(&self, url: &'_ str) -> Result<()>;
 
@@ -337,7 +345,7 @@ pub trait Storage: std::fmt::Debug + Clone + Send + Sync {
     async fn get_setting<S: Setting<'a>, 'a>(&'_ self, user: &'_ str) -> Result<S>;
 
     /// Commits a setting to the setting store.
-    async fn set_setting<S: Setting<'a>, 'a>(&self, user: &'_ str, value: S::Data) -> Result<()>;
+    async fn set_setting<S: Setting<'a> + 'a, 'a>(&self, user: &'a str, value: S::Data) -> Result<()>;
 }
 
 #[cfg(test)]