Setting a default format

[jacobthetechy]

I found in using this in my app I use the same string format in all my web pages. When adding new dates in new pages I would have a hard time remembering what exactly that format was. This solves that problem by setting a config variable to the format needed without needing to register a new jinja variable.

[miguelgrinberg]

Thanks for the contribution. The main issue that I have is that the design of this extension is such that in general the methods of this extension match the JavaScript functions in moment.js. Adding a default() method alongside format(), fromNow(), etc. makes it look like this is also part of moment.js.

[jacobthetechy]

I fully understand that.

What about this. In moment.js if you call moment().format() it will yield the current time in ISO 8601 format. If you do the same with flask-moment you get
TypeError: format() missing 1 required positional argument: 'fmt'
To be closer to how moment.js works would this be a accepted change?

default_moment_version = '2.24.0'
default_moment_sri = 'sha256-AdQN98MVZs44Eq2yTwtoKufhnU+uZ7v2kXnD5vqzZVo='
default_format = 'YYYY-MM-DDTHH:mm:ssZ'  # ISO 8601 from http://bit.ly/2FdZ5HA

##################################################################

def format(self, fmt=None, refresh=False):
        if fmt is None:
            fmt = current_app.config.get('MOMENT_DEFAULT_FORMAT', default_fmt)

        return self._render("format('%s')" % fmt, refresh)

[miguelgrinberg]

@jacobthetechy yes, supporting format() w/o arguments is reasonable, I actually wasn't aware of that option. But can we let moment.js handle the default format instead of duplicating that logic on the Python side?

[jacobthetechy]

@miguelgrinberg This is what I have come up with.

@staticmethod
def defaultFormat(fmt):
    return Markup('<script>\nmoment.defaultFormat = "%s";\n</script>' % fmt)

##################################################################

def format(self, fmt='', refresh=False):
    return self._render("format('%s')" % fmt, refresh)

To make the change you add {{moment.defaultFormat('LT')}} under {{ moment.include_moment() }}
Only difference here instead of calling moment.defaultFormat = "format_string"; per moment.js you use the function moment.defaultFormat('format_str') for the python code.

I believe its the only way for python, javascript, and jinja to all be happy. I tried to be as close to moment.js but jinja does not like {{moment.defaultFormat = "format_string"}} with using python getters and setters functions.

Thoughts?

[miguelgrinberg]

@jacobthetechy Thanks! I took parts of your PR and completed this feature. Take a look at the master branch.

[jacobthetechy]

@miguelgrinberg Beautiful! Thanks so much for adding this and allowing me to contribute.