There are several places where we write out version identifiers in various logs for structured streaming (usually v1). However, in the places where we check for this, we throw a confusing error message. Instead, we should do the following:
- Find all of the places where we do this kind of check.
- for vN where n>1 say "UnsupportedLogFormat: The file path was produced by a newer version of Spark and cannot be read by this version. Please upgrade"
- for anything else throw an error saying the file is malformed.