feat: return files as b64 in rql requests

cubicweb_api/__init__.py

@@ -26,6 +26,8 @@
 
 from cubicweb_api.exceptions import ApiException
 from cubicweb_api.util import get_api_path_prefix
+from cubicweb import Binary
+import base64
 
 
 def datetime_adapter(obj: Union[datetime, date, time], request):
@@ -38,6 +40,10 @@
     return obj.isoformat()
 
 
+def binary_adapter(binary: Binary, request):
+    return base64.b64encode(binary.read()).decode("ascii")
+
+
 def api_exception_view_deriver(view, info: IViewDeriverInfo):
     if info.options.get("use_api_exceptions"):
 
@@ -57,6 +63,7 @@
     json_renderer.add_adapter(datetime, datetime_adapter)
     json_renderer.add_adapter(date, datetime_adapter)
     json_renderer.add_adapter(time, datetime_adapter)
+    json_renderer.add_adapter(Binary, binary_adapter)
 
     api_exception_view_deriver.options = ("use_api_exceptions",)
     config.add_view_deriver(api_exception_view_deriver)