Add support for auto-deleting trashed items

Upstream will soon auto-delete trashed items after 30 days, but some people
use the trash as an archive folder, so to avoid unexpected data loss, this
implementation requires the user to explicitly enable auto-deletion.

src/db/models/cipher.rs

@@ -1,6 +1,8 @@
-use chrono::{NaiveDateTime, Utc};
+use chrono::{Duration, NaiveDateTime, Utc};
 use serde_json::Value;
 
+use crate::CONFIG;
+
 use super::{
     Attachment,
     CollectionCipher,
@@ -271,6 +273,17 @@ impl Cipher {
         Ok(())
     }
 
+    /// Purge all ciphers that are old enough to be auto-deleted.
+    pub fn purge_trash(conn: &DbConn) {
+        if let Some(auto_delete_days) = CONFIG.trash_auto_delete_days() {
+            let now = Utc::now().naive_utc();
+            let dt = now - Duration::days(auto_delete_days);
+            for cipher in Self::find_deleted_before(&dt, conn) {
+                cipher.delete(&conn).ok();
+            }
+        }
+    }
+
     pub fn move_to_folder(&self, folder_uuid: Option<String>, user_uuid: &str, conn: &DbConn) -> EmptyResult {
         User::update_uuid_revision(user_uuid, conn);
 
@@ -511,6 +524,15 @@ impl Cipher {
         }}
     }
 
+    /// Find all ciphers that were deleted before the specified datetime.
+    pub fn find_deleted_before(dt: &NaiveDateTime, conn: &DbConn) -> Vec<Self> {
+        db_run! {conn: {
+            ciphers::table
+                .filter(ciphers::deleted_at.lt(dt))
+                .load::<CipherDb>(conn).expect("Error loading ciphers").from_db()
+        }}
+    }
+
     pub fn get_collections(&self, user_id: &str, conn: &DbConn) -> Vec<String> {
         db_run! {conn: {
             ciphers_collections::table