Listers are declared as plugins via the `swh.workers` entry_point.
As such, the registry function is expected to return a dict with the
`task_modules` field (as for generic worker plugins), plus:
- `lister`: the lister class,
- `models`: list of SQLAlchemy models used by this lister,
- `init` (optionnal): hook (callable) used to initialize the lister's state
(typically, create/initialize the database for this lister).
If not set, the default implementation creates database tables (after
optionally having deleted exisintg ones) according to models declared in
the `models` register field.
There is no need for explicitely add lister task modules in the main
`conftest` module, but any new/extra lister to be tested must be registered
(the tested lister module must be properly installed in the test environment).
Also refactor a bit the cli tools:
- add support for the standard --config-file option at the 'lister' group
level,
- move the --db-url to the 'lister' group,
- drop the --lister option for the `swh lister db-init` cli tool:
initializing (especially with --drop-tables) the database for a single
lister is unreliable, since all tables are created using a sibgle MetaData
(in the same namespace).
This is needed by the (refactored) db init mechanism, since this later uses
the main declarative base class (thus the main MetaData instance) to gather
tables to be created/dropped.
instead of converting that column as a string
As a side effect, bitbucket wise, we provided improperly the after query
parameter as a date not url encoded. This resulted in improper api response from
bitbucket's (we received from time to time the same next index as the current
one).
Related T1826
Get rid of the class based task definition in favor of decorator-based
task declarations.
Doing so, we can get rid of core/tasks.py
Task names are explicitely set to keep compatibility with task
definitions in schedulers' database.
This also add debug statements at the beginning and end of each lister
task.
