let custom result renderer print json line for catalog-translate

datalad_catalog/translate.py

@@ -99,6 +99,18 @@ class MetaTranslate(ValidatedInterface):
 
     _examples_ = []
 
+    @staticmethod
+    def custom_result_renderer(res, **kwargs):
+        """This result renderer dumps the value of the 'output' key 
+        in the result record in JSON-line format -- only if status==ok"""
+        ui = ui_switcher.ui
+        ui.message(json.dumps(
+            res.get('translated_metadata'),
+            separators=(',', ':'),
+            indent=None,
+            cls=jsEncoder,
+        ))
+
     @staticmethod
     # generic handling of command results (logging, rendering, filtering, ...)
     @eval_results
@@ -197,8 +209,6 @@ def __call__(
                     message=("Metadata successfully translated"),
                     translated_metadata=translated_meta,
                 )
-                ui = ui_switcher.ui
-                ui.message(json.dumps(translated_meta, cls=jsEncoder))
             except Exception as e:
                 yield get_status_dict(
                     **res_kwargs,