Remove unused S3 list operation (#3936)

In S3, pageserver only lists tenants (prefixes) on S3, no other keys.
Remove the list operation from the API, since S3 impl does not seem to
work normally and not used anyway,

libs/remote_storage/src/lib.rs

@@ -78,9 +78,6 @@ impl RemotePath {
 /// providing basic CRUD operations for storage files.
 #[async_trait::async_trait]
 pub trait RemoteStorage: Send + Sync + 'static {
-    /// Lists all items the storage has right now.
-    async fn list(&self) -> anyhow::Result<Vec<RemotePath>>;
-
     /// Lists all top level subdirectories for a given prefix
     /// Note: here we assume that if the prefix is passed it was obtained via remote_object_id
     /// which already takes into account any kind of global prefix (prefix_in_bucket for S3 or storage_root for LocalFS)

libs/remote_storage/src/local_fs.rs

@@ -73,10 +73,8 @@ impl LocalFs {
             Ok(None)
         }
     }
-}
 
-#[async_trait::async_trait]
-impl RemoteStorage for LocalFs {
+    #[cfg(test)]
     async fn list(&self) -> anyhow::Result<Vec<RemotePath>> {
         Ok(get_all_files(&self.storage_root, true)
             .await?
@@ -91,7 +89,10 @@ impl RemoteStorage for LocalFs {
             })
             .collect())
     }
+}
 
+#[async_trait::async_trait]
+impl RemoteStorage for LocalFs {
     async fn list_prefixes(
         &self,
         prefix: Option<&RemotePath>,

libs/remote_storage/src/s3_bucket.rs

@@ -275,50 +275,6 @@ impl<S: AsyncRead> AsyncRead for RatelimitedAsyncRead<S> {
 
 #[async_trait::async_trait]
 impl RemoteStorage for S3Bucket {
-    async fn list(&self) -> anyhow::Result<Vec<RemotePath>> {
-        let mut document_keys = Vec::new();
-
-        let mut continuation_token = None;
-        loop {
-            let _guard = self
-                .concurrency_limiter
-                .acquire()
-                .await
-                .context("Concurrency limiter semaphore got closed during S3 list")?;
-
-            metrics::inc_list_objects();
-
-            let fetch_response = self
-                .client
-                .list_objects_v2()
-                .bucket(self.bucket_name.clone())
-                .set_prefix(self.prefix_in_bucket.clone())
-                .delimiter(REMOTE_STORAGE_PREFIX_SEPARATOR.to_string())
-                .set_continuation_token(continuation_token)
-                .set_max_keys(self.max_keys_per_list_response)
-                .send()
-                .await
-                .map_err(|e| {
-                    metrics::inc_list_objects_fail();
-                    e
-                })?;
-            document_keys.extend(
-                fetch_response
-                    .contents
-                    .unwrap_or_default()
-                    .into_iter()
-                    .filter_map(|o| Some(self.s3_object_to_relative_path(o.key()?))),
-            );
-
-            match fetch_response.next_continuation_token {
-                Some(new_token) => continuation_token = Some(new_token),
-                None => break,
-            }
-        }
-
-        Ok(document_keys)
-    }
-
     /// See the doc for `RemoteStorage::list_prefixes`
     /// Note: it wont include empty "directories"
     async fn list_prefixes(

libs/remote_storage/src/simulate_failures.rs

@@ -20,7 +20,6 @@ pub struct UnreliableWrapper {
 /// Used to identify retries of different unique operation.
 #[derive(Debug, Hash, Eq, PartialEq)]
 enum RemoteOp {
-    List,
     ListPrefixes(Option<RemotePath>),
     Upload(RemotePath),
     Download(RemotePath),
@@ -75,12 +74,6 @@ impl UnreliableWrapper {
 
 #[async_trait::async_trait]
 impl RemoteStorage for UnreliableWrapper {
-    /// Lists all items the storage has right now.
-    async fn list(&self) -> anyhow::Result<Vec<RemotePath>> {
-        self.attempt(RemoteOp::List)?;
-        self.inner.list().await
-    }
-
     async fn list_prefixes(
         &self,
         prefix: Option<&RemotePath>,