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Answering to invalid requests

This is a tested document. The following instructions are used for initialization:

>>> from lino import startup
>>> startup('lino_book.projects.min2.settings.doctests')
>>> from lino.api.doctest import *

We are going to send some invalid AJAX requests to lino_xl.lib.contacts.RolesByPerson, a slave table on person.

>>> contacts.RolesByPerson.master
<class 'lino_xl.lib.contacts.models.Person'>

Simulate an AJAX request:

>>> headers = dict(HTTP_X_REQUESTED_WITH='XMLHttpRequest')
>>> headers.update(REMOTE_USER='robin')
>>> test_client.force_login(rt.login('robin').user)

Here is a valid request:

>>> url = "/api/contacts/RolesByPerson?fmt=json&start=0&limit=15&mt=8&mk=114"
>>> res = test_client.get(url, **headers)
>>> print(res.status_code)
200
>>> d = AttrDict(json.loads(res.content.decode()))
>>> d.count
1
>>> print(d.title)
Mr Hans Altenberg is contact person for

Specifying an invalid primary key for the master (5114 in the example below) will internally raise an ObjectDoesNotExist exception, which in turn will cause an HttpResponseBadRequest response (i.e. status code 400):

>>> import logging
>>> logger = logging.getLogger("django.request")
>>> logger.setLevel(logging.CRITICAL)

>>> settings.SITE.strict_master_check = True
>>> url = "/api/contacts/RolesByPerson?fmt=json&start=0&limit=15&mt=8&mk=114114"
>>> res = test_client.get(url, **headers)  
AjaxExceptionResponse BadRequest: MissingRow(Person matching query does not exist. (pk=114114))
in request GET /api/contacts/RolesByPerson?fmt=json&start=0&limit=15&mt=8&mk=114114
TRACEBACK:
...

>>> url = "/api/contacts/RolesByPerson?fmt=json&start=0&limit=15&mt=8&mk=foo"
>>> res = test_client.get(url, **headers)  
AjaxExceptionResponse BadRequest: MissingRow(Field 'id' expected a number but got 'foo'. (pk=foo))
in request GET /api/contacts/RolesByPerson?fmt=json&start=0&limit=15&mt=8&mk=foo
TRACEBACK:
...

Since RolesByPerson has a known master class (i.e. Person), the mt url parameter is ignored: an invalid value for mt does not raise an exception:

>>> url = "/api/contacts/RolesByPerson?fmt=json&start=0&limit=15&mt=8888&mk=114"
>>> res = test_client.get(url, **headers)
>>> print(res.status_code)
200

Request data not supplied

After 20170410 the following AJAX request no longer raises a real exception but continues to log it. Raising an exception had the disadvantage of having an email sent to the ADMINS, which was just disturbing and not helpful because it had no "request data supplied". Now the end user gets an appropriate message because it receives a status code 400.

>>> url = '/api/cal/EventsByProject?_dc=1491615952104&fmt=json&rp=ext-comp-1306&start=0&limit=15&mt=13&mk=188'
>>> res = test_client.get(url, **headers)  
AjaxExceptionResponse Http404: cal.EventsByProject is not a class
in request GET /api/cal/EventsByProject?_dc=1491615952104&fmt=json&rp=ext-comp-1306&start=0&limit=15&mt=13&mk=188
TRACEBACK:
...

>>> res.status_code
400
>>> #print(json.loads(res.content)['message'])
>>> print(res.content.decode())
Http404: cal.EventsByProject is not a class