Comments on: SimpleBlog Part 3 - many-to-many relationships

By: mackieboy

mackieboy — Wed, 01 Aug 2007 02:56:31 +0000

help…really am a starter here.
I’m having problems when calling flush-
>>>t1.flush
there is this raise exceptions.SQLError…how can i fix it?
Im using python 2.4.
thanks

By: Sam D.

Sam D. — Sat, 28 Jul 2007 12:37:58 +0000

The Tag class could be improved as follows:

@classmethod
def normalise_tag_name(cls, tag_name):
    return '+'.join(tag_name.lower().split())

’split()’ with no arguments will remove runs of one or more whitespace characters.

By: Cory

Cory — Thu, 22 Feb 2007 05:50:41 +0000

Instead of placing tag parsing into the model (and mixing the domain logic with the binding logic), try placing into into a validator. In Turbogears validators serve two purposes: validate and bind. From the docs, it is very easy to overlook the binding aspect of it.
Example:
class TagConvertor(String):
def topython(self, value, state):
#do string to tag(s) conversion
def frompython(self, value):
#do tag object to string conversion

You would still have to deal with the persistence aspect in either the model or a DAO layer, but you’d have slightly easier time tracking the domain logic.

Then again, this could be like take a flamethrower to an anthill.

(Let’s see it if the formatting work out, eh?)

By: Splee

Splee — Tue, 28 Nov 2006 21:28:44 +0000

No problem. FYI, you can either escape underscores with a backslash or escape each bit of code with a backtick.

Thanks for all the feedback.

By: Matthew Webber

Matthew Webber — Tue, 28 Nov 2006 15:47:17 +0000

Silly me, the above comment applies to part 4.

By: Matthew Webber

Matthew Webber — Tue, 28 Nov 2006 15:31:10 +0000

To continue my previous entry. This appears to be a problem with SQLalchemy and PostgreSQL. As a workaround, in controllers.py, change this statement in the comment function (undescore replaced by dash)

c = model.Comment(post=p, author-name=author-name,
author-email=author-email,
content=content)

so that you have
authoremail=str(authoremail),

It’s a workaround, but it might help someone.

By: Matthew Webber

Matthew Webber — Tue, 28 Nov 2006 15:27:32 +0000

I previously said
>> The code provided for downloaded fails when you add a comment. The generated SQL does not have quote marks around the value of author-email. On the other hand, author-name works ok (underscore replace by dash to avoid WordPress formatting).

By: Matthew Webber

Matthew Webber — Mon, 27 Nov 2006 16:48:22 +0000

Since you’re written some admin code, it might be worth adding a note explaining how to get to it. Here’s what I did -

Firstly, add a user via the shell
/usr/bin/tg-admin shell
u = User(username=’example’, emailaddress=’example@example.com’, displayname=’Mr Example’, password=’secret’)
g = Group(groupname=’admin’, display_name=’Administrators’)
g.users.append(u)

Then python start-simpleblog.py and point your browser to localhost:8080/admin

By: Matthew Webber

Matthew Webber — Mon, 27 Nov 2006 15:27:34 +0000

One other problem : The code provided for downloaded fails when you add a comment. The generated SQL does not have quote marks around the value of author-email. On the other hand, author-name works ok (underscore replace by dash to avoid WordPress formatting).

I’m not quite sure what is causing this. Maybe related to author-email being String rather than unicode?

Also, underscore in a comment in obviously interpreted as a formatting directive. Is there a list of such directives (and how to escape them). A quick look at the WordPress site suprsiingly failed to turn up such a list.

By: Matthew Webber

Matthew Webber — Mon, 27 Nov 2006 15:02:31 +0000

Thanks for all this useful information. A couple of minor edits :

(1) tagstable = Table( …
I prefer tagtable (singular not plural) for consistency with the naming convention used elsewhere.

(2)@param data Either a comma separated string …
When I first saw this my eye tried to interpret it as some kind of decorator, due to the @ sign and the fact that the line above it was blank, so I didn’t immediately realize it was a continued comment. Is this format a docstring convention?