Expire messages after 90 days.

This is intended to manage storage growth. A community with broadly steady traffic will now reach a steady state (ish) where the amount of storage in use stays within a steady band.

The 90 day threshold is a spitball; this should be made configurable for the community's needs.

I've also hoisted expiry out into the `app` classes, to reduce the amount of non-database work repo types are doing. This should make it easier to make expiry configurable later on.

Includes incidental cleanup and style changes.

1 files changed, 14 insertions, 0 deletions

diff --git a/src/channel/repo/broadcast.rs b/src/channel/repo/broadcast.rs
index ff16cd0..182203a 100644
--- a/src/channel/repo/broadcast.rs
+++ b/src/channel/repo/broadcast.rs
@@ -68,6 +68,20 @@ impl<'c> Broadcast<'c> {
         Ok(message)
     }
 
+    pub async fn expire(&mut self, expire_at: &DateTime) -> Result<(), sqlx::Error> {
+        sqlx::query!(
+            r#"
+                delete from message
+                where sent_at < $1
+            "#,
+            expire_at,
+        )
+        .execute(&mut *self.0)
+        .await?;
+
+        Ok(())
+    }
+
     pub async fn replay(
         &mut self,
         channel: &Channel,