Hi all, I'm trying to get a handle on Zope 3. I plan to take a bunch of Zope 3 modules and combine them in a new way. The goal is to create for myself a comfortable working environment that lets me run simple code in a small mod_wsgi environment with easy reloading and no ZODB initially. To achieve this, I need to understand what's going on in the Zope 3 code base. While the code itself is easy to understand, there are many comments in the code that suggest changes are coming soon. Please help me figure out what is meant by these comments. The first cryptic comment comes from zope.component. The _api module starts with this gem: # SiteManager API. This needs to get deprecated eventually. But... um... everything in the module uses getSiteManager(). The whole component foundation is built on it. When is it going to be replaced? With what? By whom? I'm assuming for the moment that the comment is a lie, and that getSiteManager() is not going away, since otherwise I have no foundation to build upon. I think I want to use a threading.local as my site manager. That way, I can use a different configuration for each WSGI app even if several apps run in different threads of a single Python interpreter. It looks like the zope.app.component.hooks module does something like what I want, but that module is complicated and lacks comments in the places that matter, so I'm not quite sure what it accomplishes. I'll add comments to that module if anyone can explain it fully. That led me to the zope.thread module, which is apparently deprecated already, yet zope.app.component still depends on it. Is that an hysterical accident? Shane
Previously Shane Hathaway wrote:
I think I want to use a threading.local as my site manager. That way, I can use a different configuration for each WSGI app even if several apps run in different threads of a single Python interpreter. It looks like the zope.app.component.hooks module does something like what I want, but that module is complicated and lacks comments in the places that matter, so I'm not quite sure what it accomplishes. I'll add comments to that module if anyone can explain it fully.
You can also use a paste.registry StackedObjectProxy to provide access to a thread local site manager via the standard wsgi environ. That certainly fits well with the WSGI model and other frameworks such as Pylons and Turbogears use it. I'm not sure if Zope3 exposes that properly though. Admitedly paste.registry is not the best documented code either; some cleanup there is still useful but the ideal model has not been worked out yet.
That led me to the zope.thread module, which is apparently deprecated already, yet zope.app.component still depends on it. Is that an hysterical accident?
I only learned yesterday that zope.thread is now basically just a wrapper around python 2.4's threading module so you can use that directly. Wichert. -- Wichert Akkerman <wichert@wiggy.net> It is simple to make things. http://www.wiggy.net/ It is hard to make things simple.
Wichert Akkerman wrote:
Previously Shane Hathaway wrote:
I think I want to use a threading.local as my site manager. That way, I can use a different configuration for each WSGI app even if several apps run in different threads of a single Python interpreter. It looks like the zope.app.component.hooks module does something like what I want, but that module is complicated and lacks comments in the places that matter, so I'm not quite sure what it accomplishes. I'll add comments to that module if anyone can explain it fully.
You can also use a paste.registry StackedObjectProxy to provide access to a thread local site manager via the standard wsgi environ. That certainly fits well with the WSGI model and other frameworks such as Pylons and Turbogears use it. I'm not sure if Zope3 exposes that properly though. Admitedly paste.registry is not the best documented code either; some cleanup there is still useful but the ideal model has not been worked out yet.
Thanks for the pointer. I'm not quite sure how StackedObjectProxy might fit in, but if it turns out I need it, at least now I don't have to rewrite it.
That led me to the zope.thread module, which is apparently deprecated already, yet zope.app.component still depends on it. Is that an hysterical accident?
I only learned yesterday that zope.thread is now basically just a wrapper around python 2.4's threading module so you can use that directly.
Fred Drake also confirmed that nothing needs to use zope.thread anymore. I plan to clean it up. Shane
On Tuesday 03 June 2008, Shane Hathaway wrote:
# SiteManager API. This needs to get deprecated eventually.
But... um... everything in the module uses getSiteManager(). The whole component foundation is built on it. When is it going to be replaced? With what? By whom?
This is a result of the big zope component cleanup. I forgot the details. Jim would be the best person to answer this. If he does not know, we should just remove the comment. :-) Regards, Stephan -- Stephan Richter Web Software Design, Development and Training Google me. "Zope Stephan Richter"
Shane Hathaway wrote:
Hi all,
I'm trying to get a handle on Zope 3. I plan to take a bunch of Zope 3 modules and combine them in a new way. The goal is to create for myself a comfortable working environment that lets me run simple code in a small mod_wsgi environment with easy reloading and no ZODB initially.
To achieve this, I need to understand what's going on in the Zope 3 code base. While the code itself is easy to understand, there are many comments in the code that suggest changes are coming soon. Please help me figure out what is meant by these comments.
The first cryptic comment comes from zope.component. The _api module starts with this gem:
# SiteManager API. This needs to get deprecated eventually.
I think this meant to say that the word "Site Manager" has been deprecated. Nowadays we just say component registry. In theory. I think we just found that renaming things isn't worth all the trouble.
But... um... everything in the module uses getSiteManager(). The whole component foundation is built on it. When is it going to be replaced? With what? By whom?
I think the comment can go. It's the opposite of useful right now.
I'm assuming for the moment that the comment is a lie, and that getSiteManager() is not going away, since otherwise I have no foundation to build upon.
Yup.
I think I want to use a threading.local as my site manager. That way, I can use a different configuration for each WSGI app even if several apps run in different threads of a single Python interpreter. It looks like the zope.app.component.hooks module does something like what I want, but that module is complicated and lacks comments in the places that matter, so I'm not quite sure what it accomplishes. I'll add comments to that module if anyone can explain it fully.
zope.component.getSiteManager() is a "hooked" function (using zope.hookable). That means it can be replaced by some other implementation. zope.app.component.hooks makes use of that. It replaces zope.component.getSiteManager() with an implementation that looks up a thread local variable (SiteInfo). This replacement is done in the setHooks() function which is called some time during Zope startup.
That led me to the zope.thread module, which is apparently deprecated already, yet zope.app.component still depends on it. Is that an hysterical accident?
As said previously, zope.thread.local is just a wrapper around Python's threading.local module (which was contributed by Jim based on zope.thread.local).
Shane Hathaway wrote at 2008-6-4 00:01 -0600:
... # SiteManager API. This needs to get deprecated eventually.
But... um... everything in the module uses getSiteManager(). The whole component foundation is built on it. When is it going to be replaced? With what? By whom?
I'm assuming for the moment that the comment is a lie, and that getSiteManager() is not going away, since otherwise I have no foundation to build upon.
I, too, hope (and expect) so.
I think I want to use a threading.local as my site manager. That way, I can use a different configuration for each WSGI app even if several apps run in different threads of a single Python interpreter. It looks like the zope.app.component.hooks module does something like what I want, but that module is complicated and lacks comments in the places that matter, so I'm not quite sure what it accomplishes. I'll add comments to that module if anyone can explain it fully.
That led me to the zope.thread module, which is apparently deprecated already, yet zope.app.component still depends on it. Is that an hysterical accident?
As I have read, thread local variables have been invented and implemented in Zope 3 land and donated to Python. Now, that it is in Python, the original Zope implementation can go away. Maybe, that is the purpose of the "zope.thread" module? -- Dieter
On 2008-06-04 20:28:07 +0200, "Dieter Maurer" <dieter@handshake.de> said:
Shane Hathaway wrote at 2008-6-4 00:01 -0600:
That led me to the zope.thread module, which is apparently deprecated already, yet zope.app.component still depends on it. Is that an hysterical accident?
As I have read, thread local variables have been invented and implemented in Zope 3 land and donated to Python.
Now, that it is in Python, the original Zope implementation can go away. Maybe, that is the purpose of the "zope.thread" module?
Actually zope.thread does nothing but importhing the python implementation. The module is there for backward compatibility. -- Christian Zagrodnick · cz@gocept.com gocept gmbh & co. kg · forsterstraße 29 · 06112 halle (saale) · germany http://gocept.com · tel +49 345 1229889 4 · fax +49 345 1229889 1 Zope and Plone consulting and development
participants (6)
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Christian Zagrodnick -
Dieter Maurer -
Philipp von Weitershausen -
Shane Hathaway -
Stephan Richter -
Wichert Akkerman