pageserver: refactor http deletion_queue_flush

pageserver/src/http/routes.rs

@@ -5,6 +5,7 @@ use std::collections::HashMap;
 use std::sync::Arc;
 
 use anyhow::{anyhow, Context, Result};
+use futures::TryFutureExt;
 use hyper::StatusCode;
 use hyper::{Body, Request, Response, Uri};
 use metrics::launch_timestamp::LaunchTimestamp;
@@ -24,7 +25,7 @@ use super::models::{
     TimelineCreateRequest, TimelineGcRequest, TimelineInfo,
 };
 use crate::context::{DownloadBehavior, RequestContext};
-use crate::deletion_queue::{DeletionQueueClient, DeletionQueueError};
+use crate::deletion_queue::DeletionQueueClient;
 use crate::metrics::{StorageTimeOperation, STORAGE_TIME_GLOBAL};
 use crate::pgdatadir_mapping::LsnForTimestamp;
 use crate::task_mgr::TaskKind;
@@ -1159,27 +1160,20 @@ async fn deletion_queue_flush(
 
     let execute = parse_query_param(&r, "execute")?.unwrap_or(false);
 
+    let flush = async {
+        if execute {
+            state.deletion_queue_client.flush_execute().await
+        } else {
+            state.deletion_queue_client.flush().await
+        }
+    }
+    // DeletionQueueError's only case is shutting down.
+    .map_err(|_| ApiError::ShuttingDown);
+
     tokio::select! {
-        flush_result = async {
-            if execute {
-                state.deletion_queue_client.flush_execute().await
-            } else {
-                state.deletion_queue_client.flush().await
-            }
-        } => {
-            match flush_result {
-                Ok(())=> {
-                    json_response(StatusCode::OK, ())
-                },
-                Err(e) => {
-                    match e {
-                        DeletionQueueError::ShuttingDown => {
-            Err(ApiError::ShuttingDown)
-                        }
-                    }
-                }
-            }
-        },
+        res = flush => {
+            res.map(|()| json_response(StatusCode::OK, ()))?
+        }
         _ = cancel.cancelled() => {
             Err(ApiError::ShuttingDown)
         }