DEFAULTED_ON_CREATE not supported in alternate testing DB?

Hi! I’ve successfully set up an alternate testing DB with SQLite as instructed in the readme, however when running my tests, I get the following error:

django.db.utils.InterfaceError: Error binding parameter 1 - probably unsupported type

This appears to come from a field I have defined as:

is_active = models.BooleanField(custom=True,
                                db_column='Is_Active__c', 
                                default=models.DEFAULTED_ON_CREATE)

A quick look at the execute method in django/db/backends/sqlite3/base.py reveals that the Is_Active__c param that django is trying to save is: <salesforce.backend.operations.DefaultedOnCreate object at 0x10f233c50> … instead of True/False. Changing that param value to either True or False while debugging does indeed solve the problem.

Is there a known issue working with DEFAULTED_ON_CREATE in alternate DBs? Am I missing some kind of configuration?

Thanks!

[hynekcer]

Most problems are already solved by the PR for version 1.0.

Instead of your proposal testing_default a parameter for DefaultedOnCreate() is implemented, e.g.:

from django.utils.timezone import now

class ...:
    is_active = models.BooleanField(default=models.DefaultedOnCreate(True))
    created_date = models.DateTimeField(default=models.DefaultedOnCreate(now),
                                        sf_read_only=models.READ_ONLY)

A documentation for it is in wiki Introspection and Special Attributes of Fields.

Missing part: tests (a new test project that runs on Salesforce then on ‘default’ and possibly also with and without migrations)

[hynekcer]

The right solution should be simpler then A), B) or your code.

The algorithm of inspectdb command was stable long time and it ignored default values that were useful only with non-Salesforce databases.

I wrote a patch for inspectdb

• Support for introspection with DefaultedOnCreate(value). 6aab51bc

to export more information, e.g.

    default=models.DefaultedOnCreate(False)`,
    default=models.DefaultedOnCreate('NotSeen'), choices=[('NotSeen', 'Not Seen'), ...],

Nothing is changed in the backend implementation yet, but you can still simplify your code by:

class TestableBooleanField(models.BooleanField):
    def __init__(self, **kwargs):
        if settings.ENV == 'test' and isinstance(kwargs['default']), DefaultedOnCreate):
            kwargs['default'] = kwargs['default'].arg
        super(TestableBooleanField, self).__init__(default=default, **kwargs)

(not fixed, but a progress)

• A problem is also in Salesforce with objects that were just created if they are saved once more without previous refreshing fields that were assigned by Salesforce defaults. We can try a special request that writes some fields and reads some fields in the same request. Useful for those fields with sf_read_only attribute (e.g. a formula that depends on ohter fields) or with DefaultedOnCreate

• No field on the Salesforce platform expects a default value from the application.