return Option from media::data::search_file_metadata

This is useful to easily distinguish missing files from corrupted keys.
All existing usage sites have been modified so there is no behavior
change in this commit.

src/database/key_value/media.rs

@@ -1,4 +1,4 @@
-use ruma::{api::client::error::ErrorKind, OwnedMxcUri};
+use ruma::OwnedMxcUri;
 
 use crate::{
     database::KeyValueDatabase,
@@ -158,21 +158,21 @@ impl service::media::Data for KeyValueDatabase {
         mxc: OwnedMxcUri,
         width: u32,
         height: u32,
-    ) -> Result<(FileMeta, MediaFileKey)> {
+    ) -> Result<Option<(FileMeta, MediaFileKey)>> {
         let mut prefix = mxc.as_bytes().to_vec();
         prefix.push(0xFF);
         prefix.extend_from_slice(&width.to_be_bytes());
         prefix.extend_from_slice(&height.to_be_bytes());
         prefix.push(0xFF);
 
-        let (key, _) =
+        let Some((key, _)) = self.mediaid_file.scan_prefix(prefix).next()
-            self.mediaid_file.scan_prefix(prefix).next().ok_or(
+        else {
-                Error::BadRequest(ErrorKind::NotFound, "Media not found"),
+            return Ok(None);
-            )?;
+        };
 
         let key = MediaFileKey::new(key);
         let parts = MediaFileKeyParts::try_from(&key)?;
-        Ok((parts.meta, key))
+        Ok(Some((parts.meta, key)))
     }
 
     fn delete_file_metadata(&self, key: MediaFileKey) -> Result<()> {

src/service/media.rs

@@ -1,14 +1,17 @@
 use std::io::Cursor;
 
 use image::imageops::FilterType;
-use ruma::{http_headers::ContentDisposition, OwnedMxcUri};
+use ruma::{
+    api::client::error::ErrorKind, http_headers::ContentDisposition,
+    OwnedMxcUri,
+};
 use tokio::{
     fs::{self, File},
     io::{AsyncReadExt, AsyncWriteExt},
 };
 use tracing::{debug, warn};
 
-use crate::{services, utils, Result};
+use crate::{services, utils, Error, Result};
 
 mod data;
 
@@ -96,7 +99,7 @@ impl Service {
         &self,
         mxc: OwnedMxcUri,
     ) -> Result<Option<(FileMeta, Vec<u8>)>> {
-        if let Ok((meta, key)) = self.db.search_file_metadata(mxc, 0, 0) {
+        if let Ok(Some((meta, key))) = self.db.search_file_metadata(mxc, 0, 0) {
             let path = services().globals.get_media_file(&key);
             let mut file_data = Vec::new();
             let Ok(mut file) = File::open(path).await else {
@@ -114,10 +117,13 @@ impl Service {
     /// Deletes a media object and all associated thumbnails.
     #[tracing::instrument(skip(self))]
     pub(crate) async fn delete(&self, mxc: OwnedMxcUri) -> Result<()> {
-        let (_, key) =
+        let (_, key) = self
-            self.db.search_file_metadata(mxc.clone(), 0, 0).inspect_err(
+            .db
+            .search_file_metadata(mxc.clone(), 0, 0)
+            .inspect_err(
                 |error| warn!(%error, "Failed to find original media key"),
-            )?;
+            )?
+            .ok_or(Error::BadRequest(ErrorKind::NotFound, "Media not found"))?;
 
         let thumbnails = self.db.search_thumbnails_metadata(mxc)?;
         for (_, thumbnail_key) in thumbnails {
@@ -292,7 +298,7 @@ impl Service {
         let (width, height, crop) =
             Self::thumbnail_properties(width, height).unwrap_or((0, 0, false));
 
-        if let Ok((meta, key)) =
+        if let Ok(Some((meta, key))) =
             self.db.search_file_metadata(mxc.clone(), width, height)
         {
             debug!("Using saved thumbnail");
@@ -303,7 +309,8 @@ impl Service {
             return Ok(Some((meta, file.clone())));
         }
 
-        let Ok((meta, key)) = self.db.search_file_metadata(mxc.clone(), 0, 0)
+        let Ok(Some((meta, key))) =
+            self.db.search_file_metadata(mxc.clone(), 0, 0)
         else {
             debug!("Original image not found, can't generate thumbnail");
             return Ok(None);

src/service/media/data.rs

@@ -17,7 +17,7 @@ pub(crate) trait Data: Send + Sync {
         mxc: OwnedMxcUri,
         width: u32,
         height: u32,
-    ) -> Result<(FileMeta, MediaFileKey)>;
+    ) -> Result<Option<(FileMeta, MediaFileKey)>>;
 
     fn delete_file_metadata(&self, key: MediaFileKey) -> Result<()>;