[development] node types should not be changeable, operations need hooks

[Jeremy Epstein]

On 8/24/06, Peter Wolanin <pwolanin at gmail.com> wrote:
> First- a question.  What is the use case for this?  If I don't like
> the name of a node type (e.g. 'story'), I can just create an
> alternative.  Trying to account for the possibility that the name of
> the type has changed (to me) makes the code look rather more
> convoluted than necessary and seems to introduce the potential for
> more bugs.

I was the one that pushed for (and developed) the ability to change
the machine-readable name of a node type, and I feel very strongly
that this feature should remain in core, and that it is a feature
worth maintaining, despite it making the node type system somewhat
more vulnerable to bugs. There are a number of important use cases for
this feature.

What happens when a user decides that they don't like the
machine-readable name that they picked a few months ago, and that they
want to change it? What happens when that user's site already has
hundreds of nodes of that type? If the user is forced to delete the
old node type and to create a new one, then all the old nodes become
corrupted (and there's no way to avoid this, since the system would
have no way of knowing that they need to be updated to the new type).

Not to mention the fact that from a usability point of view, it is
absolutely unacceptable to have to delete and then re-create a node
type, simply in order to update the value of one field. You've pointed
out the possibility that users may want to update the names of their
node types at some point. It therefore follows that we should make
this as easy for them as possible, which is what the current system
does.

> Allowing users to change the node type will potentially create
> problems- for example with organic groups, where the names of "group"
> types are saved in a variable and there is no hook to let the module
> know they have been changed.

For module-defined node types, (a) the default behaviour is to NOT
allow the machine-readable name to be changed, and (b) if this
behaviour is modified, and the machine-readable name is modifiable,
the original name is always still available, because it's stored in
the 'orig_type' field of the 'node_type' table. The 'orig_type' thing
also applies to user-defined node types. So modules that need a
constant, permanent key to reference, can rely on 'orig_type' instead
of 'type'. That's what it's there for.

> So, I propose that this be removed and alslo that a hook be created to
> allow modules to act when a node type is deleted.

-1 to this feature being removed, but +1 to creating a hook to allow
modules to respond to changes to a node type. I have created an issue
for this task:

http://drupal.org/node/80257

I have also filed a bug for the 'permission names do not change when
node type name changes' issue:

http://drupal.org/node/80253

> issue posting: http://drupal.org/node/77990

And I have responded to that issue.

Cheers,
Jaza.