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Hi,

Le Tue, 14 May 2013 06:55:38 +0200,
Tamer Higazi <th982a@googlemail.com> a écrit:

> 1. What is the difference between a global and a localSiteManager from
> the zope.component package?!
>
> How do I have to understand that a "globalSiteManager" resists in
> memory, and a localSiteManager is persistent ?!
>
> Could somebody of you explain it to me?!

Yes, there are two kinds of complementary "registries" (or "site
managers"):
- a global one, mainly build by ZCML (or "static") declarations
- a local one, which is made of persistent components registered into
the ZODB. Local components are "contextual", so are only available
(by default) to objects "attached" to the site manager inside which
these components are defined. This registry is mainly specific to
Zope applications so if you build a ZCA-based application outside of
Zope, you will probably don't have a local registry.

Where you are looking for a component, search is made at first in the
local registry, then in the global one.


> 2. What is the difference between an adapter and a utility ?! I
> register an adapter as well the same way as I do with a utility, and
> I query those 2 as well. But what's the point there?!

A utility is a simple named component which provides an interface;
it's generally a singleton.
An adapter, on the opposite, takes one or more objects arguments (each
providing a given interface) to return an object providing another
interface.

Regards,
Thierry

P.S.: please avoid cross-posts!
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Hi Thierry!
Thanks for your lat response, meanwhile things are getting more and more
clear to me.


I got it meanwhile to register utilities through the globalSiteManager,
and I am now very familiar now with zca basics (though that I have much
more to learn of it's API)

There is something totally unclear to me!


I got 2 applications registered in the
"/storage/PyProjects/ztfyAPP/etc/configure.zcml"

tamer@office /storage/PyProjects/ztfyAPP/src $ ls -lA
insgesamt 16
drwxr-xr-x 2 tamer tamer 4096 9. Jun 07:40 appsx
drwxr-xr-x 2 tamer tamer 4096 20. Mai 16:13 appsx.egg-info
drwxr-xr-x 4 tamer tamer 4096 9. Jun 07:43 webapp
drwxr-xr-x 2 tamer tamer 4096 20. Mai 02:35 webapp.egg-info


that is "webapp" and "appsx"

so far so good.

At /storage/PyProjects/ztfyAPP/src/appsx/__init__.py:

I globally registered a class, which definied previously as a utility.


from Services import *
from zope.component import getGlobalSiteManager
from zope.component import getUtilitiesFor,queryUtility

gsmx = getGlobalSiteManager()

VAT = VATServices()
gsmx.registerUtility(VAT,IVATServices,'VAT')



now I want to have access this utility in the global sitemanager from
one other app.

/storage/PyProjects/ztfyAPP/src/webapp/__init__.py:

from myhello import HelloView
from zope.component import getGlobalSiteManager

#print list(getUtilitiesFor('IVatServices'))

gsmx2 = getGlobalSiteManager()
gsmx2.queryUtility(IVATServices,'VAT').Hallo()


I thought it is in the memory. Okay, that the interface is not available
in the other application is clear.


But, how do I access components or utilities registered in a different
application globally, at one other application at all ?!



Tamer


Am 14.05.2013 09:22, schrieb Thierry Florac:
>
> Hi,
>
> Le Tue, 14 May 2013 06:55:38 +0200,
> Tamer Higazi <th982a@googlemail.com> a écrit:
>
>> 1. What is the difference between a global and a localSiteManager from
>> the zope.component package?!
>>
>> How do I have to understand that a "globalSiteManager" resists in
>> memory, and a localSiteManager is persistent ?!
>>
>> Could somebody of you explain it to me?!
>
> Yes, there are two kinds of complementary "registries" (or "site
> managers"):
> - a global one, mainly build by ZCML (or "static") declarations
> - a local one, which is made of persistent components registered into
> the ZODB. Local components are "contextual", so are only available
> (by default) to objects "attached" to the site manager inside which
> these components are defined. This registry is mainly specific to
> Zope applications so if you build a ZCA-based application outside of
> Zope, you will probably don't have a local registry.
>
> Where you are looking for a component, search is made at first in the
> local registry, then in the global one.
>
>
>> 2. What is the difference between an adapter and a utility ?! I
>> register an adapter as well the same way as I do with a utility, and
>> I query those 2 as well. But what's the point there?!
>
> A utility is a simple named component which provides an interface;
> it's generally a singleton.
> An adapter, on the opposite, takes one or more objects arguments (each
> providing a given interface) to return an object providing another
> interface.
>
> Regards,
> Thierry
>
> P.S.: please avoid cross-posts!
>

_______________________________________________
Zope maillist - Zope@zope.org
https://mail.zope.org/mailman/listinfo/zope
** No cross posts or HTML encoding! **
(Related lists -
https://mail.zope.org/mailman/listinfo/zope-announce
https://mail.zope.org/mailman/listinfo/zope-dev )

Hi Tamer,

Le Sun, 09 Jun 2013 17:30:26 +0200,
Tamer Higazi <th982a@googlemail.com> a écrit:

> Hi Thierry!
> Thanks for your lat response, meanwhile things are getting more and
> more clear to me.
>
> I got it meanwhile to register utilities through the
> globalSiteManager, and I am now very familiar now with zca basics
> (though that I have much more to learn of it's API)
>
> There is something totally unclear to me!
>
>
> I got 2 applications registered in the
> "/storage/PyProjects/ztfyAPP/etc/configure.zcml"
>
> tamer@office /storage/PyProjects/ztfyAPP/src $ ls -lA
> insgesamt 16
> drwxr-xr-x 2 tamer tamer 4096 9. Jun 07:40 appsx
> drwxr-xr-x 2 tamer tamer 4096 20. Mai 16:13 appsx.egg-info
> drwxr-xr-x 4 tamer tamer 4096 9. Jun 07:43 webapp
> drwxr-xr-x 2 tamer tamer 4096 20. Mai 02:35 webapp.egg-info
>
>
> that is "webapp" and "appsx"
>
> so far so good.
>
> At /storage/PyProjects/ztfyAPP/src/appsx/__init__.py:
>
> I globally registered a class, which definied previously as a utility.
>
>
> from Services import *
> from zope.component import getGlobalSiteManager
> from zope.component import getUtilitiesFor,queryUtility
>
> gsmx = getGlobalSiteManager()
>
> VAT = VATServices()
> gsmx.registerUtility(VAT,IVATServices,'VAT')
>
>
>
> now I want to have access this utility in the global sitemanager from
> one other app.
>
> /storage/PyProjects/ztfyAPP/src/webapp/__init__.py:
>
> from myhello import HelloView
> from zope.component import getGlobalSiteManager
>
> #print list(getUtilitiesFor('IVatServices'))
>
> gsmx2 = getGlobalSiteManager()
> gsmx2.queryUtility(IVATServices,'VAT').Hallo()
>
>
> I thought it is in the memory. Okay, that the interface is not
> available in the other application is clear.
>
>
> But, how do I access components or utilities registered in a different
> application globally, at one other application at all ?!


There are two points about your configuration:

1. It's a personal choice but I never add code inside a ZTFY.webapp
environment. My application code is always written in external
packages, and only referenced in my execution environments (by
updating setup.py, buildout.cfg and configure.zcml).

2. Anyway, if both of your applications are correctly referenced in
configure.zcml and included in the global registry, you should be
able to use any of it's components from anywhere in your code. So my
question is simple: are you sure that the second application (appsx)
is correctly included in your execution environment and registered?
You can check that by using the apidoc tool (in debug mode, using
http://localhost:8080/++apidoc++ by default) and searching for one
of your interfaces or utilities registered in this package...

Regards,
Thierry

_______________________________________________
Zope maillist - Zope@zope.org
https://mail.zope.org/mailman/listinfo/zope
** No cross posts or HTML encoding! **
(Related lists -
https://mail.zope.org/mailman/listinfo/zope-announce
https://mail.zope.org/mailman/listinfo/zope-dev )