Improve error message when storing

src/main.rs

@@ -93,24 +93,37 @@ struct RetrieveResponse {
     value: String,
 }
 
-/// Store data on the filesystem
-async fn store_data(key: &str, value: &[u8], expires_at: SystemTime) -> Result<(), String> {
+async fn get_file_path(key: &str) -> String {
     let dir_name = format!("{}/{}", STORAGE_DIR, &key[..2]);
     let file_path = format!("{}/{}", dir_name, &key[2..]);
-    let metadata_path = format!("{}.meta", file_path);
+    
+    file_path
+}
 
-    create_dir_all(&dir_name).await.map_err(|e| e.to_string())?;
+/// Store data on the filesystem
+async fn store_data(key: &str, value: &[u8], expires_at: SystemTime) -> Result<(), tide::Error> {
+    let file_name = get_file_path(key).await;
+    let file_path = Path::new(&file_name);
 
-    let mut file = File::create(&file_path).await.map_err(|e| e.to_string())?;
-    file.write_all(value).await.map_err(|e| e.to_string())?;
+    // Check if key exists
+    if file_path.exists().await {
+        return Err(tide::Error::from_str(StatusCode::Conflict, "Key already exists"));
+    }
+
+    create_dir_all(file_path).await.map_err(|e| tide::Error::new(StatusCode::InternalServerError, e))?;
+
+    let metadata_path = format!("{}.meta", file_name);
+
+    let mut file = File::create(&file_path).await.map_err(|e| tide::Error::new(StatusCode::InternalServerError, e))?;
+    file.write_all(value).await.map_err(|e| tide::Error::new(StatusCode::InternalServerError, e))?;
 
     let metadata = Metadata {
         expires_at: system_time_to_unix(expires_at)
     };
 
-    let metadata_json = serde_json::to_string(&metadata).map_err(|e| e.to_string())?;
-    let mut meta_file = File::create(&metadata_path).await.map_err(|e| e.to_string())?;
-    meta_file.write_all(metadata_json.as_bytes()).await.map_err(|e| e.to_string())?;
+    let metadata_json = serde_json::to_string(&metadata).map_err(|e| tide::Error::new(StatusCode::InternalServerError, e))?;
+    let mut meta_file = File::create(&metadata_path).await.map_err(|e| tide::Error::new(StatusCode::InternalServerError, e))?;
+    meta_file.write_all(metadata_json.as_bytes()).await.map_err(|e| tide::Error::new(StatusCode::InternalServerError, e))?;
 
     Ok(())
 }
@@ -127,9 +140,14 @@ async fn retrieve_data(key: &str) -> Result<Vec<u8>, String> {
 /// Handler for the /store endpoint
 async fn handle_store(mut req: Request<()>) -> tide::Result<Response> {
     // Parse the JSON body
-    let data: StoreRequest = req.body_json().await.map_err(|_| {
-        tide::Error::from_str(StatusCode::BadRequest, "Invalid JSON payload")
-    })?;
+    let data: StoreRequest = match req.body_json().await {
+        Ok(data) => data,
+        Err(e) => {
+            return Ok(Response::builder(StatusCode::BadRequest)
+                .body(format!("Invalid request: {}", e))
+                .build());
+        }
+    };
 
     // Validate the key
     if data.key.len() != 64 || !data.key.chars().all(|c| c.is_ascii_hexdigit()) {
@@ -139,25 +157,36 @@ async fn handle_store(mut req: Request<()>) -> tide::Result<Response> {
     }
 
     // Decode the value from Base64
-    let value_bytes = base64::decode(&data.value).map_err(|_| {
-        tide::Error::from_str(StatusCode::BadRequest, "Invalid Base64 value")
-    })?;
+    let value_bytes = match base64::decode(&data.value) {
+        Ok(value) => value,
+        Err(e) => {
+            return Ok(Response::builder(StatusCode::BadRequest)
+                .body(format!("Invalid request: {}", e))
+                .build());
+        }
+    };
 
     let now = SystemTime::now();
     let live_for = if let Some(ttl) = data.ttl { Duration::from_secs(ttl) } else { Duration::from_secs(DEFAULT_TTL) };
     let expires_at = now.checked_add(live_for).ok_or(tide::Error::from_str(StatusCode::BadRequest, "Invalid ttl"))?;
 
     // Store the data
-    store_data(&data.key, &value_bytes, expires_at).await.map_err(|e| {
-        tide::Error::from_str(StatusCode::InternalServerError, e)
-    })?;
-
-    // Respond with success
-    Ok(Response::builder(StatusCode::Ok)
-        .body(serde_json::to_value(&ApiResponse {
-            message: "Data stored successfully.".to_string(),
-        })?)
-        .build())
+    match store_data(&data.key, &value_bytes, expires_at).await {
+        Ok(()) => {
+            Ok(Response::builder(StatusCode::Ok)
+                .body(serde_json::to_value(&ApiResponse {
+                    message: "Data stored successfully.".to_string(),
+                })?)
+                .build())
+        }
+        Err(e) => {
+            Ok(Response::builder(e.status())
+                .body(serde_json::to_value(&ApiResponse {
+                    message: e.to_string(),
+                })?)
+                .build())
+        }
+    }
 }
 
 async fn handle_retrieve(req: Request<()>) -> tide::Result<Response> {