_message.py: Use element_name & element_key instead of unique_idtpollard/messageobject

Adding the element full name and display key into all element related
messages removes the need to look up the plugintable via a plugin
unique_id just to retrieve the same values for logging and widget
frontend display. Relying on plugintable state is also incompatible
if the frontend will be running in a different process, as it will
exist in multiple states.

The element full name is now displayed instead of the unique_id,
such as in the debugging widget. It is also displayed in place of
'name' (i.e including any junction prepend) to be more informative.

1 files changed, 6 insertions, 1 deletions

diff --git a/src/buildstream/source.py b/src/buildstream/source.py
index b513fdb2a..c5fb61415 100644
--- a/src/buildstream/source.py
+++ b/src/buildstream/source.py
@@ -308,10 +308,11 @@ class Source(Plugin):
 
     def __init__(self, context, project, meta, *, alias_override=None, unique_id=None):
         provenance = meta.config.get_provenance()
+        # Set element_name member before parent init, as needed for debug messaging
+        self.__element_name = meta.element_name         # The name of the element owning this source
         super().__init__("{}-{}".format(meta.element_name, meta.element_index),
                          context, project, provenance, "source", unique_id=unique_id)
 
-        self.__element_name = meta.element_name         # The name of the element owning this source
         self.__element_index = meta.element_index       # The index of the source in the owning element's source list
         self.__element_kind = meta.element_kind         # The kind of the element owning this source
         self.__directory = meta.directory               # Staging relative directory
@@ -1076,6 +1077,10 @@ class Source(Plugin):
         length = min(len(key), context.log_key_length)
         return key[:length]
 
+    @property
+    def _element_name(self):
+        return self.__element_name
+
     # _get_args_for_child_job_pickling(self)
     #
     # Return data necessary to reconstruct this object in a child job process.