You are here: Home Blog Topics pyramid


Jul 25, 2013

First impressions with Kotti

by Mike Cullerton — last modified Jul 25, 2013 03:15 PM
Filed Under:

The boss is away this week, so I'm learning about Kotti. Here's how I solved the problem of limiting a content type to the root of the site.

The Basics

My application is very simple. There are two content types; Forum and Idea. A forum is added to the root of the site, and then ideas are added to the forum.

I was already familiar with kotti's documentation and the tutorial there, so getting the basic application running was very easy.

First, I set up a virtualenv, and installed kotti along with a skeleton for my package.

$ virtualenv --no-site-packages kotti_agora-27
$ cd kotti_agora-27/
$ ./bin/pip install -r
$ wget
$ ./bin/pip install kotti_paster
$ ./bin/paster create -t kotti_addon kotti_agora
$ cd kotti_agora/
$ ../bin/python develop

The pip install step takes a little while.

From there, I was able to add code to kotti_agora, including my two content types, their views, and some kotti plumbing to wire it all up. For the most part, I stole everything from the kotti tutorial mentioned above and from the source code for kotti_blog.

Limiting Ideas to a Forum

The first problem I had to solve was limiting ideas to a forum. Kotti has an addable_to attribute when creating content types. I set the addable_to attribute of Idea to Forum.

class Idea(Content):
    id = Column(Integer(), ForeignKey(''), primary_key=True)
    body = Column(Text())
    date = Column('date', UTCDateTime())

    type_info = Content.type_info.copy(

Limiting Forum to the Site Root

At this point, I had an application that worked. I could add a forum to the root of my site, and then add ideas to it.

But, you could add a Forum to any document in the site, and you could add more than one Forum.

I asked a couple questions about this on the #kotti irc channel and was pointed to an example in kotti_media. The solution to both problems is a custom TypeInfo. This one checks whether we have the site root for our context, and if a Forum already exists.

class ForumTypeInfo(TypeInfo):

    def addable(self, context, request):
        """only add once, and only at the root"""
        addable = context == get_root()
        child_type_already_added = self in [
                c.type_info for c in context.children]
        return addable and not child_type_already_added

I then use ForumTypeInfo for Forum's type_info. Note how this is different from the Idea class above.

class Forum(Content):
    id = Column(Integer(), ForeignKey(''), primary_key=True)

    type_info = ForumTypeInfo(

Add Forum Automatically

For a little icing on the cake, I decided to add the Forum to the site automatically, using a populator. I put mine in If forum does not exist, the populator adds it.

def populate():
    root = get_root()
    if 'forum' not in root.keys():
        root['forum'] = Forum(title=u'Forum')

Then add configuration to your .ini file.

kotti.populators = kotti_agora.populate

Pretty slick.

Now, there is one Forum and it only exists at the root of the site. And, if it doesn't exist, it is created when the site starts.


There are so many options for python web programmers these days. My expertise is with Plone, but after using Pyramid for a few small projects I wanted to try out Kotti CMS. Something about Pyramid seems right to me, and Kotti fits the same mold. Kind of like working on a bicycle or a VW bus. I can see it all. It fits in my head nicely, and the problems are approachable. 

Kotti has great documentation, which helps you get started. The project is relatively young and there are some holes in the narrative documentation, but it has evolved in the short time I've used it.

And, a big shout out to the #kotti irc channel. Very friendly. Very helpful.


Apr 08, 2013

How to open SSH links in iTerm 2

by Mike Cullerton — last modified Apr 08, 2013 04:45 PM
Filed Under:

When I switched to iTerm 2, it wouldn't open ssh links for me. Instead, it opened new tabs. I finally solved the problem with a simple configuration change.

I know some of you have this problem. I've seen a few references to it on the net, but no solutions. iTerm 2 won't open ssh links.

I have a pyramid application that uses boto to query ec2 instances and then posts information about the instances--including an ssh link, to a web page on my laptop.

The ssh links open fine in iTerm. I couldn't get them to open in iTerm 2 though. Instead, they just opened new tabs.

I really like using iTerm 2, so to 'solve' the problem, I added the actual ssh shell command for each of the instances as text on the page.

To open an ssh connection to an instance, I simply copy the ssh command, click the link, paste the ssh command into the new terminal tab, and hit return.

Hey, it works.

Every once in a while, when it really bothers me, I try to figure out a real solution.

Today was one of those days.

The solution turned out to be pretty simple.

In the iTerm 2 Preferences, under the Profiles tab, General section, change the Command to Login shell.

Now, when I click on one of the links, it opens correctly in iTerm 2.

I hope it works for you too.

*Note that you must first have iTerm 2 set up to accept ssh connections. Preferences->Profiles->General->URL Schemes


Copyright © 2003-2018 Core Software Group | 303/809-1001 | Fort Collins, Colorado | All rights reserved.