From 1d25b238a4671ca6630361b7d3cc1e02eb8eaf6d Mon Sep 17 00:00:00 2001
From: Giovanni Gargiulo <nemo83@users.noreply.github.com>
Date: Wed, 21 Feb 2024 11:20:38 +0000
Subject: [PATCH] fix: immediately return empty response for batch request with
 empty list of subjects (#12)

---
 .../api/controller/MetadataApiController.java | 20 ++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/api/src/main/java/org/cardanofoundation/tokenmetadata/registry/api/controller/MetadataApiController.java b/api/src/main/java/org/cardanofoundation/tokenmetadata/registry/api/controller/MetadataApiController.java
index afd8d47..1122ea7 100644
--- a/api/src/main/java/org/cardanofoundation/tokenmetadata/registry/api/controller/MetadataApiController.java
+++ b/api/src/main/java/org/cardanofoundation/tokenmetadata/registry/api/controller/MetadataApiController.java
@@ -27,16 +27,22 @@ public class MetadataApiController implements MetadataApi {
     @Override
     public ResponseEntity<BatchResponse> getSubjects(final BatchRequest body) {
         try {
-            final Map<String, TokenMetadata> subjects = v1ApiMetadataIndexer.findSubjectsSelectProperties(
-                    body.getSubjects(),
-                    body.getProperties());
-            if (subjects.isEmpty()) {
-                return new ResponseEntity<>(HttpStatus.NO_CONTENT);
-            } else {
+            if (body.getSubjects().isEmpty()) {
                 final BatchResponse response = new BatchResponse();
-                response.setSubjects(new ArrayList<>(subjects.values()));
                 return new ResponseEntity<>(response, HttpStatus.OK);
+            } else {
+                final Map<String, TokenMetadata> subjects = v1ApiMetadataIndexer.findSubjectsSelectProperties(
+                        body.getSubjects(),
+                        body.getProperties());
+                if (subjects.isEmpty()) {
+                    return new ResponseEntity<>(HttpStatus.NO_CONTENT);
+                } else {
+                    final BatchResponse response = new BatchResponse();
+                    response.setSubjects(new ArrayList<>(subjects.values()));
+                    return new ResponseEntity<>(response, HttpStatus.OK);
+                }
             }
+
         } catch (final IllegalArgumentException e) {
             return new ResponseEntity<>(HttpStatus.BAD_REQUEST);
         }