Content Types

In CMF, a content type is defined as a bag of settings (the type information, controlled within the “types tool”), as well as factory code which generates an instance of that content. It is possible to construct and enumerate content types using APIs defined on the types tool.

Pyramid itself has no such concept, but an addon package named repoze.lemonade has a barebones replacement.

Factory Type Information

A factory type information object in CMF allows you to associate a title, a description, an internationalization domain, an icon, an initial view name, a factory, and a number of security settings with a type name. Each type information object knows how to manufacture content objects that match its type.

Pyramid certainly enforces none of these concepts in any particular way, but repoze.lemonade does.

repoze.lemonade Content

repoze.lemonade provides a reasonably handy directive and set of helper functions which allow you to:

  1. Associate a interface with a factory function, making it into a “content type”.
  2. Enumerate all interfaces associated with factory functions.

Note

Using this pattern is often plain silly, as it’s usually just as easy to actually import a class implementation and create an instance directly using its constructor. But it can be useful in cases where you want to address some set of constructors uniformly without doing direct imports in the code which performs the construction, or if you need to make content construction uniform across a diverse set of model types, or if you need to enumerate some set of information about “content” types. It’s left as an exercise to the reader to determine under which circumstances using this pattern is an appropriate thing to do. Hint: not very often, unless you’re doing the indirection solely to aid content-agnostic unit tests or if you need to get an enumerated subset of content type information to aid in UI generation. That said, this is a tutorial about how to get CMF-like features in Pyramid, so we’ll assume the pattern is useful to readers.

See the repoze.lemonade package for more information, particularly its documentation for “content”.

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