Buildout: order of ‘extends’ configuration files

Yet another word to the wise: take care of your ordering of the ‘extends’ configuration files within your buildout.  It makes complete sense, and especially so with respect to version pinning: the later configuration’s versions will be the last one applied.

So, it makes a lot of sense (in hindsight!) that this configuration, and the fact I have version pins in my base.cfg, isn’t going to end well:

[buildout]
extends =
    base.cfg
    http://good-py.appspot.com/release/dexterity/1.0b2

The Dexterity version pins are going to override the ones I have in my base.cfg.  This …

in Python · Thu 06 January 2011

Bad relationships: RelationChoice, RelationCatalog and removed Dexterity content in Plone

Disclaimer: this post isn’t giving relationship advice (or..it is in some twisted way).  Unsurprisingly, removing content in Plone via the ZMI when Plone says something can’t be deleted is likely to cause problems.

In my case, the fact I removed a Dexterity-based container (“Project”) caused users to no longer add or edit content of my Project type.  The reason for this boiled down to my use of RelationChoice fields, in order link Projects to Person objects and vice versa.  The backend storage for the RelationChoice field is an instance of z3c.relationfield.index.RelationCatalog, and this keeps …

in IT, Work · Tue 26 October 2010

Plone/Zope: Truncating a Data.fs back to a certain date/time

Okay. So, anyone out here who’s listening — particularly those overly-enthusiastic users — don’t try to recursively wget your Plone site (or other CMS, for that matter) whilst you’re logged in with an account that can make edits. It will lead to a very bad situation where your site administrator and technical team need to step in and fix your mistakes. For the uninitiated, a loose recursive wget (when logged in with some degree of Edit rights) will hit every link that’s on your pages, and I mean in the (X)HTML source. For a Plone site, this …

in Plone · Tue 20 July 2010

Plone: running Plone without copies of blobs

Having a bad day? Just bombed your only copies of some files that you’d been storing as blobs together with your Plone database? Maybe you had the blobs stored incorrectly on your Zeo client, rather than the server, and then in a hasty effort to free some space (due to an on-going issue with blobs eating HDD space), deleted them. Whoops..they’re gone and their references are still in your Plone database. Or, in a less disastrous situation, maybe you just want to be able to run your Plone database without needing lost blobs? Read on.The suggestion …

in Plone · Tue 13 July 2010

Plone: Overrides.zcml gets auto-included with z3c.autoinclude

Unsurprisingly, specifying a z3c.autoinclude entry point in your Plone product egg means your ZCML gets automatically included. That’s great because it means you don’t have to specify your product under the ZCML section of your instance in buildout. One thing that isn’t so obvious (it’s not mentioned that I can see on plone.org) is that if your package is marked for ZCML autoinclude, then Plone will automatically load an overrides.zcml file in your product.

Nothing hits you like a slippery wet fish in the face more than hitting this issue and having it …

in Plone · Tue 13 July 2010

Plone 4: Local Zeo blobs conflict with Plone instance

As the title suggests, there’s a conflict between a Zeo database instance being run together with a Plone 4/Zope instance, and them trying to share the same blob storage folder.  But, this only happens if you misunderstand or incorrectly set the option of  shared-blob = off, and blob-storage to be the same location as for Zeo in your buildout. If that previous set of (seemingly jumbled) thoughts doesn’t make any sense to you, then move along, nothing to see here.

By default, at the time of writing, blob support within Zeo runs with the bushylayout, and creates …

in Plone · Tue 06 July 2010

Plone: SiteManager leftovers; not the good kind

Leftovers are typically useful when they’re in your fridge at home. They mean you don’t have to mess around making lunch for the next day for work, and can just grab them, and walk right out the door. Now, leftovers in the zope.component SiteManager aren’t …

in Plone · Mon 28 June 2010

Plone, Dexterity, and Incorrect Widgets

A nice ‘gotcha’ is the distinction between Zope’s schema.Date and schema.Datetime. The difference is obvious and straightforward when the two terms are laid out side-by-side: one is for dates only and the other adds a time component. Where things fell down for me in my usage of these fields with a Dexterity-based content type in Plone is the human component. When these fields are mashed in together within a lot of other text/Python/names, it’s easy to miss those 4 little letters of ‘time’. This lead me trying to use a DatetimeFieldWidget when I really …

in Plone · Mon 21 June 2010

Plone/Zope: Using LDAPUserFolder with posixGroups

Due to various reasons, the Products.LDAPUserFolder package available for Plone and Zope doesn’t support POSIX groups.  The ‘official’ (ish) reason for this is because of the fact that these groups don’t store full distinguished names (DNs) for members.  It makes some degree of sense, because a user ID like ‘david.test’ isn’t strictly unique.  On the other hand, these types of groups are quite common in LDAP implementations; not supporting them without giving it at least half a shot to find the user seems a bit strange.

Here’s where a quick patch steps in. Thanks …

in Plone · Thu 03 June 2010

Virtualenv, Python 2.4, Plone 3.x and Lucid Lynx (Ubuntu 10.04)

These titles of my posts just keep getting longer and longer.  For those of you paying close attention (I know who you are), this is the next in my series of getting the above-mentioned tools working together. Previously, it was Centos 5.x, Jaunty (9.04), Karmic (9.10) and now Lucid (10.04).  Only subtly different, each of this distributions has pretty much called for its own post on the matter of getting a working Plone 3.x / Python 2.4 virtualenv installation going.  So, here goes this time around.

in Plone · Wed 12 May 2010