What's new in CubicWeb 3.19

New functionalities

  • implement Cross Origin Resource Sharing (CORS) (see #2491768)
  • system_source.create_eid can return a range of IDs, to reduce overhead of batch entity creation

Behaviour Changes

  • The anonymous property of Session and Connection is now computed from the related user login. If it matches the anonymous-user in the config the connection is anonymous. Beware that the anonymous-user config is web specific. Therefore, no session may be anonymous in a repository only setup.

New Repository Access API

Connection replaces Session

A new explicit Connection object replaces Session as the main repository entry point. A Connection holds all the necessary methods to be used server-side (execute, commit, rollback, call_service, entity_from_eid, etc...). One obtains a new Connection object using session.new_cnx(). Connection objects need to have an explicit begin and end. Use them as a context manager to never miss an end:

with session.new_cnx() as cnx:
cnx.execute('INSERT Elephant E, E name "Babar"')
cnx.commit()
cnx.execute('INSERT Elephant E, E name "Celeste"')
cnx.commit()
# Once you get out of the "with" clause, the connection is closed.

Using the same Connection object in multiple threads will give you access to the same Transaction. However, Connection objects are not thread safe (hence at your own risks).

repository.internal_session is deprecated in favor of repository.internal_cnx. Note that internal connections are now safe by default, i.e. the integrity hooks are enabled.

Backward compatibility is preserved on Session.

dbapi vs repoapi

A new API has been introduced to replace the dbapi. It is called repoapi.

There are three relevant functions for now:

  • repoapi.get_repository returns a Repository object either from an URI when used as repoapi.get_repository(uri) or from a config when used as repoapi.get_repository(config=config).
  • repoapi.connect(repo, login, **credentials) returns a ClientConnection associated with the user identified by the credentials. The ClientConnection is associated with its own Session that is closed when the ClientConnection is closed. A ClientConnection is a Connection-like object to be used client side.
  • repoapi.anonymous_cnx(repo) returns a ClientConnection associated with the anonymous user if described in the config.

repoapi.ClientConnection replaces dbapi.Connection and company

On the client/web side, the Request is now using a repoapi.ClientConnection instead of a dbapi.Connection. The ClientConnection has multiple backward compatible methods to make it look like a dbapi.Cursor and dbapi.Connection.

Sessions used on the Web side are now the same as the ones used Server side. Some backward compatibility methods have been installed on the server side Session to ease the transition.

The authentication stack has been altered to use the repoapi instead of the dbapi. Cubes adding new elements to this stack are likely to break.

New API in tests

All current methods and attributes used to access the repo on CubicWebTC are deprecated. You may now use a RepoAccess object. A RepoAccess object is linked to a new Session for a specified user. It is able to create Connection, ClientConnection and web side requests linked to this session:

access = self.new_access('babar') # create a new RepoAccess for user babar
with access.repo_cnx() as cnx:
# some work with server side cnx
cnx.execute(...)
cnx.commit()
cnx.execute(...)
cnx.commit()with access.client_cnx() as cnx:
# some work with client side cnx
cnx.execute(...)
cnx.commit()with access.web_request(elephant='babar') as req:
# some work with web request
elephant_name = req.form['elephant']
req.execute(...)
req.cnx.commit()

By default testcase.admin_access contains a RepoAccess object for the default admin session.

API changes

  • RepositorySessionManager.postlogin is now called with two arguments, request and session. And this now happens before the session is linked to the request.
  • SessionManager and AuthenticationManager now take a repo object at initialization time instead of a vreg.
  • The async argument of _cw.call_service has been dropped. All calls are now synchronous. The zmq notification bus looks like a good replacement for most async use cases.
  • repo.stats() is now deprecated. The same information is available through a service (_cw.call_service('repo_stats')).
  • repo.gc_stats() is now deprecated. The same information is available through a service (_cw.call_service('repo_gc_stats')).
  • repo.register_user() is now deprecated. The functionality is now available through a service (_cw.call_service('register_user')).
  • request.set_session no longer takes an optional user argument.
  • CubicwebTC does not have repo and cnx as class attributes anymore. They are standard instance attributes. set_cnx and _init_repo class methods become instance methods.
  • set_cnxset and free_cnxset are deprecated. The database connection acquisition and release cycle is now more transparent.
  • The implementation of cascading deletion when deleting composite entities has changed. There comes a semantic change: merely deleting a composite relation does not entail any more the deletion of the component side of the relation.
  • _cw.user_callback and _cw.user_rql_callback are deprecated. Users are encouraged to write an actual controller (e.g. using ajaxfunc) instead of storing a closure in the session data.
  • A new entity.cw_linkable_rql method provides the rql to fetch all entities that are already or may be related to the current entity using the given relation.

Deprecated Code Drops

  • The session.hijack_user mechanism has been dropped.
  • EtypeRestrictionComponent has been removed, its functionality has been replaced by facets a while ago.
  • the old multi-source support has been removed. Only copy-based sources remain, such as datafeed or ldapfeed.