3dbb4078b3
SRC_LOG_LEVELS became an empty dict when per-module log levels were dropped, and env.py keeps it only as a legacy name. opengauss.py is the last thing in the tree that still indexes it, at module scope, so importing the module raises KeyError: 'RAG' and any deployment on VECTOR_DB=opengauss dies the first time it touches the vector store. The factory imports it lazily, which is why nothing else trips over it. Deleting the line is the whole fix: every other vector backend takes getLogger(__name__) and inherits the root level.
colbert.py passes an argument to a message with no placeholder to consume it:
log.info('ColBERT: Loading model', name)
At INFO, which is the default, logging evaluates 'ColBERT: Loading model' % ('colbert-ir/colbertv2.0',) and raises TypeError: not all arguments converted during string formatting. The record is swallowed by handleError, so loading a ColBERT reranker prints '--- Logging error ---' plus a traceback to stderr instead of the model name. Adding %s prints the name and drops the traceback.