Prune database from settings

src/comms.rs

@@ -16,6 +16,7 @@ pub enum ToOverlordMessage {
     ProcessIncomingEvents,
     PostReply(String, Vec<Tag>, Id),
     PostTextNote(String, Vec<Tag>),
+    PruneDatabase,
     PullFollowMerge,
     PullFollowOverwrite,
     PushFollow,

src/db/mod.rs

@@ -32,6 +32,7 @@ use crate::error::Error;
 use crate::globals::GLOBALS;
 use rusqlite::Connection;
 use std::fs;
+use tokio::task;
 
 // This sets up the database
 #[allow(clippy::or_fun_call)]
@@ -120,3 +121,18 @@ fn upgrade(db: &Connection, mut version: u16) -> Result<(), Error> {
     tracing::info!("Database is at version {}", version);
     Ok(())
 }
+
+pub async fn prune() -> Result<(), Error> {
+    let sql = include_str!("prune.sql");
+    task::spawn_blocking(move || {
+        let maybe_db = GLOBALS.db.blocking_lock();
+        let db = maybe_db.as_ref().unwrap();
+        let mut stmt = db.prepare(sql)?;
+        stmt.execute(())?;
+        Ok::<(), Error>(())
+    }).await??;
+
+    *GLOBALS.status_message.write().await = "Database prune has completed.".to_owned();
+
+    Ok(())
+}

src/db/prune.sql

@@ -0,0 +1,22 @@
+
+PRAGMA foreign_keys = ON;
+
+-- Delete stale kind=0 events (keep the last one)
+DELETE FROM event WHERE kind=0 AND created_at != (SELECT max(created_at) FROM event as event_inner WHERE kind=0 AND pubkey=event.pubkey);
+
+-- Delete stale kind=3 events (keep the last one)
+DELETE FROM event WHERE kind=3 AND created_at != (SELECT max(created_at) FROM event as event_inner WHERE kind=3 AND pubkey=event.pubkey);
+
+-- Delete stale kind=10001 events (keep the last one)
+DELETE FROM event WHERE kind=10001 AND created_at != (SELECT max(created_at) FROM event as event_inner WHERE kind=10001 AND pubkey=event.pubkey);
+
+-- Delete kind=1 events older than 1 week
+DELETE FROM event WHERE kind!=0 AND kind!=3 AND kind!=10001 AND created_at < strftime('%s', 'now') - 60*60*24*7;
+
+-- Due to foreign keys and cascades, the following will also be cleaned up
+--   event_relationship
+--   event_hashtag
+--   event_tag
+--   event_seen
+
+VACUUM;

src/overlord/mod.rs

@@ -448,6 +448,13 @@ impl Overlord {
                     }
                 });
             }
+            ToOverlordMessage::PruneDatabase => {
+                let _ = tokio::spawn(async move {
+                    if let Err(e) = crate::db::prune().await {
+                        tracing::error!("{}", e);
+                    }
+                });
+            }
             ToOverlordMessage::PostReply(content, tags, reply_to) => {
                 self.post_reply(content, tags, reply_to).await?;
             }

src/ui/settings.rs

@@ -143,6 +143,16 @@ pub(super) fn update(app: &mut GossipUi, _ctx: &Context, _frame: &mut eframe::Fr
         ui.add(Slider::new(&mut app.settings.max_fps, 2..=60).text("Frames per second"));
     });
 
+    ui.add_space(12.0);
+    ui.separator();
+    ui.add_space(12.0);
+
+    if ui.button("Prune Database")
+        .on_hover_text("This will delete overridden events, events older than a week, and related data while keeping everything important. It make make Gossip somewhat unresponsive until it is complete.")
+        .clicked() {
+        let _ = GLOBALS.to_overlord.send(ToOverlordMessage::PruneDatabase);
+    }
+
     ui.add_space(12.0);
     ui.separator();
     ui.add_space(24.0);