Binary detection logic fails when pg version reports OS details

[nickgsc]

On our database instance, the details of the OS are included in the version string that is reported

postgres@linus-db:~/aiven-db-migrate$ psql --version
psql (PostgreSQL) 12.1 (Ubuntu 12.1-1.pgdg18.04+1)

This interferes with the binary detection logic in the migration code as it includes that in the paths it tries to search:

2020-10-30 15:18:14,652	PGMigrate	ERROR	Couldn't find pg version '12.1 (Ubuntu 12.1-1.pgdg18.04+1)' bin dir, tried: ['/usr/pgsql-12.1 (Ubuntu 12.1-1.pgdg18.04+1)/bin', '/usr/pgsql-12.1 (Ubuntu 12.1-1.pgdg18/bin', '/usr/lib/postgresql/12.1 (Ubuntu 12.1-1.pgdg18.04+1)/bin', '/usr/lib/postgresql/12.1 (Ubuntu 12.1-1.pgdg18/bin']

[nickgsc]

I worked around this in the meantime by hard-coding the correct path into the method in pgutils.py

[gabriel-tincu]

Good point about this.... I'll make it a future task to have a more reliable way of extracting the version

[gabriel-tincu]

@nickgsc this should be fixed here https://github.com/aiven/aiven-db-migrate/pull/12/files#diff-1bbaa53eabd0222b8a9f7e3b3b9dea8dc5dc1e46a0ff66e27597926bf510d441R190, among other things