How to use multiple bespoke 400 pages with error text

[hyan...@googlemail.com]

I'm creating my own bespoke 404 / 400 error page by editing routes.py like this:

routes_onerror = [('app/400', '/app/default/custom_400.html')]

and I have 2 questions: 

1) The custom_400 page is displayed when from within a controller, I call e.g. 

raise HTTP(400, "my error message text")

How do I access/display the error message text within my custom_400.html page?

2) If it is is not an HTML view which is being called, but a JSON view, I want to return a JSON page instead which, for example, reads {"error":"my error message text"}. How do I do that? Can I just create a custom_400.json view, and remove the .html from my line in routes.py?

Thanks for any help

[Jose C]

If I remember correctly, the message in your point 1) will only display if you do not have a custom page.... it overrides the default plain http error code text that web2py produces.

As to point 2) which may help you solve point 1) as well, I think you may need to use dynamic error pages.

For example, I have a controller called 'errors' that looks like this:

def error_404():
    """ Dynamic 404 error page... receives
        <Storage {'ticket': 'None',
                  'code': '404',
                  'request_url': '/the_url',
                  'requested_uri': 'the_full_uri'}>
    """
    # Set response code to original error, otherwise it will be 302.
    response.status = 404

    is_property = '/propert' in request.vars.requested_uri.lower()

    if is_property:
        return response.render('errors/error_404_property.html', {})  # This is an ordinary view so pass variables in the dict as 2nd parameter.
    else:
        return response.render('errors/error_404_general.html', {})

Then I have two (normal) views in /applications/myapp/views/errors that correspond to the two views used above with different messages.

In routes.py:

    routes_onerror = [
            (r'*/400', r'/static/400.html'),    # bad request
            (r'*/403', r'/static/403.html'),    # forbidden
            (r'*/404', r'/errors/error_404'),    # DYNAMIC - not found page
            ]

Having said all that, to return json on 400 error, I would test whether this works for you:

No views need to be created. In the errors controller, in the function you create, just return dict(error='my err message')    In routes_onerror, try:  ('app/400', '/app/default/custom_400.json').  Web2py's automatic json conversion should kick in and return the json if all goes well.  Remember to restart your app each time you change anything in routes.py.

See: http://www.web2py.com/books/default/chapter/29/03/overview?search=json#Simple-examples for how the .json extension should automatically work.

HTH,