diff --git a/pkg/api/handlers/compat/images_build.go b/pkg/api/handlers/compat/images_build.go
index d4c8c0743a..4a11065b2b 100644
--- a/pkg/api/handlers/compat/images_build.go
+++ b/pkg/api/handlers/compat/images_build.go
@@ -804,6 +804,7 @@ func BuildImage(w http.ResponseWriter, r *http.Request) {
 					if err := enc.Encode(m); err != nil {
 						logrus.Warnf("failed to json encode error %v", err)
 					}
+					flush()
 					m.Aux = nil
 					m.Stream = fmt.Sprintf("Successfully built %12.12s\n", imageID)
 					if err := enc.Encode(m); err != nil {
diff --git a/test/python/docker/compat/test_images.py b/test/python/docker/compat/test_images.py
index ac9a8d671e..cb2931b3ee 100644
--- a/test/python/docker/compat/test_images.py
+++ b/test/python/docker/compat/test_images.py
@@ -4,6 +4,7 @@
 import io
 import os
 import unittest
+import json
 
 from docker import errors
 
@@ -125,6 +126,14 @@ def test_build_image(self):
         self.assertEqual(image.labels["apple"], labels["apple"])
         self.assertEqual(image.labels["grape"], labels["grape"])
 
+    def test_build_image_via_api_client(self):
+        api_client = self.docker.api
+        for line in api_client.build(path="test/python/docker/build_labels"):
+            try:
+                parsed = json.loads(line.decode("utf-8"))
+            except json.JSONDecodeError as e:
+                raise IOError(f"Line '{line}' was not JSON parsable")
+            assert "errorDetail" not in parsed
 
 if __name__ == "__main__":
     # Setup temporary space