Revision as of 15:14, 24 March 2009

Some Notes from Pywebsvcs-talk@lists.sourceforge.net List

My scrapbook of notes and extracts from the Pywebsvcs mailing list...

Finding Methods

Fragments extracted from Pywebsvcs-talk Digest, Vol 34, Issue 6

Below only lists available functions....

....
s=ServiceProxy(url,tracefile=sys.stdout)
....
from ZSI.schema import GED
print s._methods.keys()
for x in s._methods.keys():
        for i in s._methods[x][0].callinfo.inparams:
                print 'Inparameters',i.name,i.type,GED(*i.type)
        for i in s._methods[x][0].callinfo.outparams:
                print 'outparameters',i.name,i.type,GED(*i.type)

Try This

Fragments extracted from Pywebsvcs-talk Digest, Vol 34, Issue 5

Try this:

>>> from ZSI.ServiceProxy import ServiceProxy as sp
>>> s = sp("yoururl.wsdl")
>>> dir(s)

Ok. This does what? Connects me?

1. Now, there is a request function that I need to use. How can I find it? Where is it?

 dir(s)
['__doc__', '__init__', '__module__', '_asdict', '_cachedir', '_call',
'_force', '_kw', '_lazy', '_load', '_load_schema', '_methods', '_mod',
'_name', '_nullpyclass', '_port', '_pyclass', '_service', '_url',
'_wsdl']

2. The service I'm connecting to has a function that takes 3 arguments, so I assume somewhere I should be able to do:

processed_xml=somecallfunction(username='lucas',password='xyz',file='myxmlfile.xml')

How do I call that function? How do I list available "call functions"

? Anything else I need to do?

Actually the problem seems to be:

It looks like WCF hides some of their stuff in the WSDL, but they tell you
where it is with their import schemas:

<wsdl:types>
- <xsd:schema targetNamespace="http://tempuri.org/Imports">
  <xsd:import
schemaLocation="http://someurl.com/service.svc?xsd=xsd0"
namespace="http://tempuri.org/" />
  <xsd:import
schemaLocation="http://someurl.com/service.svc?xsd=xsd1"
namespace="http://schemas.microsoft.com/2003/10/Serialization/" />
  </xsd:schema>
</wsdl:types>

Is there a way I can get my ServiceProxy read that file?

 from ZSI.ServiceProxy import ServiceProxy as sp
>>>>> s = sp("yoururl.wsdl")

?????
It doesn't seem to follow the target schema?

Not sure who's fault was that....,I got the people to modify the wsdl
and now I can see the "submit and rate" function.

1. How do I use it ..From soappy examples I can see I could do the
following, but in zsi?

from SOAPpy import WSDL
>>> server = WSDL.Proxy('/path/to/your/GoogleSearch.wsdl')

server.methods.keys()                                  2
[u'doGoogleSearch', u'doGetCachedPage', u'doSpellingSuggestion']
>>> callInfo = server.methods['doGoogleSearch']
>>> for arg in callInfo.inparams:                          3
...     print arg.name.ljust(15), arg.type

and
results = server.doGoogleSearch(key, 'mark', 0, 10, False, "",
...     False, "", "utf-8", "utf-8")

2. I tried with zsi:

url='http:/someurl....com'

from ZSI.ServiceProxy import ServiceProxy as sp
s=sp(url)

f=open(somefile.xml','r')
file=f.readlines()
f.close()

 s.SubmitAndRate('myusername','mypassword','1234',file)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/var/lib/python-support/python2.5/ZSI/ServiceProxy.py", line
324, in __call__
    return self.parent()._call(self.__name__, self.soapheaders)(*args, **kwargs)
  File "/var/lib/python-support/python2.5/ZSI/ServiceProxy.py", line
204, in call_closure
    raise TypeError, 'Not supporting SOAPENC:Arrays or XSD:List'
TypeError: Not supporting SOAPENC:Arrays or XSD:List

On the Usefulness of ZSI

Extracted from Pywebsvcs-talk Digest, Vol 30, Issue 3

Works fine for me, as far as client WSDL/SOAP is concerned.  But the
bigger problem is XSD files that turn quickly turn into monstrosities. I
use   Code Synthesis' xsd-tree for parsing xsd specifications and
serializing the data, then pack them in with ZSI to send them off to the
server.  I've tried Java (jaxb,jaxm), mono -C# (with Microsofts XSD),
gSoap and Perl soap::lite.   I found the java variations seriously over
engineered (a class file per element), (the mono XSD was seriously
deficient. Its /c to generate c++ didn't work on linux, and C# under
mono is really just a specification), and Perl soap::lite out of date
(didn't work with the .net services I had to deal with)   Had I had some
more time, I might have made gSoap work, but ZSI tackled the WSDL I had
to work with right out of the tarbox. And when something was unclear or
didn't work, I could step through with the python debugger to track it
down.   I work on linux.  If I had been developing on M$, I would have
used their stuff, but I still think I would stick with Code Synthesis
and C++ for parsing xsd.  It's a fantastic program with unbelievably
good support for an open source product, and works with Visual
Studio,too.

ZSI's support is ok, too.  The turnaround on questions is pretty slow.
But if you don't mind stepping through the code, you can usually fix the
problem yourself.  And there seem to be plenty of people using it.

Roger Evans

Having spent too much time recently looking at python/SOAP stuff I am
pretty sure ZSI is the only one out there that will go any way towards
handling the WSDL part for you.

I am more than willing for someone to correct me on this if I missed anything.

-- 
Peter Ellis <peter.ellis@finalhaven.org>

alphabetical order of 'self.attribute_typecode_dict'

This should be irrelevant, although order is important for canonicalization for an entirely different matter.

I think you could retain your ordering by replacing the underlying dict with your own dict subclass that maintains a list too.

	Topic._attrs = OrderDict()

Something like Collection, although obviously this is a bit old.

from ZSI.wstools.Utility import Collection

class Collection(UserDict):
     """Helper class for maintaining ordered named collections."""
     default = lambda self,k: k.name
     def __init__(self, parent, key=None):
         UserDict.__init__(self)
         self.parent = weakref.ref(parent)
         self.list = []
         self._func = key or self.default

     def __getitem__(self, key):
         if type(key) is type(1):
             return self.list[key]
         return self.data[key]

     def __setitem__(self, key, item):
         item.parent = weakref.ref(self)
         self.list.append(item)
         self.data[key] = item

     def keys(self):
         return map(lambda i: self._func(i), self.list)

     def items(self):
         return map(lambda i: (self._func(i), i), self.list)

     def values(self):
         return self.list

Newbie Stuff

Upgrade to ZSI-2.1a and this package is no longer required.

-josh


On May 14, 2008, at 4:02 PM, freeav8r wrote:

> Hi all:
>
> I’m new to ZSI and apache and I’m having
> difficulty getting my first ZSI web service up and
> running.
>
> I installed apache with no problems and also installed
> mod_python.  I ran the mod_python “hello world”
> test by changing the httpd.conf file with the
> following entry:
>
> <Directory "C:/Program Files/Apache Software
> Foundation/Apache2.2/htdocs/test">
>   AddHandler mod_python .py
>   PythonHandler mptest
>   PythonDebug On
> </Directory>
>
> The “Hello world” worked fine.
>
> I tried the mod_python example (2.1.3) found here:
> http://pywebsvcs.sourceforge.net/zsi.html
>
> Because of the apache config entry above, I created
> the following to files with the below names:
>
> ========== mptest.py =========
> from ZSI import dispatch
> from mod_python import apache
>
> import MyHandler
> mod = __import__('encodings.utf_8', globals(),
> locals(), '*')
> mod = __import__('encodings.utf_16_be', globals(),
> locals(), '*')
>
> def handler(req):
>    dispatch.AsHandler(modules=(MyHandler,),
> request=req)
>    return apache.OK
> ========== end mptest.py =======
>
> =========MyHandler.py ========
> def hello():
>    return "Hello, world"
>
> def echo(*args):
>    return args
>
> def average(*args):
>    sum = 0
>    for i in args: sum += i
>    return sum / len(args)
> ========= end MyHandler.py ========
>
> When I request the mptest.py file I get the following
> error:
>
>
>  File "C:\Program
> Files\Python25\Lib\site-packages\ZSI\parse.py", line
> 54, in __init__
>    from xml.dom.ext.reader import PyExpat
>
> ImportError: No module named ext.reader
>
> I'm running python 2.5 and the lastest stable versions
> of apache, mod_python, and ZSI.
>
>
> Any ideas?
>
> -freeav8r

http persistent connection

I think you can do this by using your own transport.

Here is the relevant code from client.py:

         self.h = transport(netloc, None, **self.transdict)
         self.h.connect()
         self.SendSOAPData(soapdata, url, soapaction, **kw)

So basically you'd need something like a Singleton that delegates to  
actual transports, so you can maintain these instances between soap  
calls and reuse the same transport when appropriate.

But I'm not sure about the rest, you'll need a transport that  
implements HTTP persistent connections.  Maybe twisted is a better bet  
than the python httplib.

-josh

On May 17, 2008, at 2:52 PM, Kleber Carriello de Oliveira wrote:

> Sirs,
>
> I'm trying to use ZSI with http persistent connection, does anyone  
> know if it's possible? If yes can you send me one example?
>
> My problem is that I need to call one API about 500 times per  
> second... I believe that using persistent connection I can reach  
> this number instead of open and close one tcp connection each time I  
> do a call.
>
> Thanks in advance,
>
> Kleber Carriello
>
>
>      Abra sua conta no Yahoo! Mail, o único sem limite de espaço  
> para armazenamento!
> http://br.mail.yahoo.com/

ServiceProxy

> server = ServiceProxy(w, pyclass=True, tracefile=sys.stdout)

ZSI 2.0.0 as a whole supports complex type, but there's a serious bug
in ServiceProxy in 2.0.0 which prevents using it with asdict=False
(ServiceProxy in 2.0.0 doesn't have the pyclass keyword) [1]. I
suggest upgrading to 2.1a1 where the broken part of ServiceProxy has
been rewritten and now works.

[1] Specifically ServiceProxy._call always passes args or kwargs
through to binding.Send regardless of what asdict is set to, so that
with complex types calls to proxy methods complain that binding.Send
is getting tuples (i.e. args) or dicts (i.e. kwargs) instead of the
expected complex types.

ZSI Thread Safe?

I don't think so but threads in python are restricted by the GIL so  
all state is shared between threads.  So if you're changing an objects  
state all threads will "instantly" see it.  This is up to you to manage.

-josh


On May 14, 2008, at 12:56 AM, Esteban wrote:

> After some testing, I confirmed that I cannot share the same
> ServicePort on different clients as it is not thread safe (I expected
> this result actually...)
>
> Using a different one for each client seems to work. However, I am
> concerned about race conditions that are difficult to detect. Does
> somebody know whether the servicePorts share any resources that could
> lead to the wrong result if accessing through several threads?
>
> Thanks,
> -- Esteban.
>
> On May 13, 10:01 am, Esteban <robe...@gmail.com> wrote:
>> Hi there,
>>
>> I am writting a client for a Web Service using ZSI 2.0.
>> I have to poll different operations on the same service, using
>> different time intervals.
>> I'd like to use a separate thread for each operation, so that one of
>> them can execute while others are either sleeping or blocked waiting
>> for the service's response.
>>
>> Is the service binding returned by
>> ServiceLocator().getServicePort(url, **kw) thread safe (so that it  
>> can
>> be shared by all client threads)? In case it is not, would it be any
>> problem if I create a different service  locator as above on each
>> thread? I am not sure if they would share any common stuff in
>> downstream...
>>
>> I read a similar post (http://groups.google.com/group/pywebsvcs/
>> browse_thread/thread/cf77b338ccb1e526/26a4e4dcfec57564?
>> lnk=gst&q=thread#26a4e4dcfec57564)
>> but I did not really get it clear and I think it was more focused on
>> the service side (as it talked about Apache for example).
>>
>> Any other suggestion to approach this problem are appreciated ;)
>>
>> Thanks for your help,
>> -- Esteban
>>

Simple Client Example

Joshua Boverhof escribió: 
You can use WSDL too (wsdl2py), but here is a simple client example
-josh


$ python
Python 2.5.1 (r251:54863, May 23 2007, 10:06:54)
[GCC 4.0.0 20041026 (Apple Computer, Inc. build 4061)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
 >>> from ZSI.client import *
 >>> dir()
['AUTH', 'Address', 'AnyElement', 'AnyType', 'Binding', 'Cookie',  
'EvaluateException', 'FaultException', 'FaultFromFaultMessage',  
'NamedParamBinding', 'ParsedSoap', 'SoapWriter', 'String', 'Struct',  
'TC', 'TypeCode', 'UNICODE_ENCODING', 'WSActionException',  
'ZSI_SCHEMA_URI', '__builtins__', '__doc__', '__name__', 'base64',  
'httplib', 'time', 'types', 'urlparse']

 >>> import sys
 >>> cli = NamedParamBinding("http://www.google.com",  
tracefile=sys.stdout)
 >>> cli.Hello()
_________________________________ Tue May 13 23:09:21 2008 REQUEST:
<SOAP-ENV:Envelope xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/ 
" xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"  
xmlns:ZSI="http://www.zolera.com/schemas/ZSI/" xmlns:xsd="http://www.w3.org/2001/XMLSchema 
" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" SOAP- 
ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"><SOAP- 
ENV:Header></SOAP-ENV:Header><SOAP-ENV:Body><Hello></Hello></SOAP- 
ENV:Body></SOAP-ENV:Envelope>
_________________________________ Tue May 13 23:09:22 2008 RESPONSE:
501
Not Implemented
-------
Date: Wed, 14 May 2008 06:09:22 GMT
Content-Type: text/html; charset=UTF-8
Server: gws
Content-Length: 1343
...
...

 >>> cli.Hello(first="Jenn", lastname="Duerr", number=1)
_________________________________ Tue May 13 23:11:03 2008 REQUEST:
<SOAP-ENV:Envelope xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/ 
" xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"  
xmlns:ZSI="http://www.zolera.com/schemas/ZSI/" xmlns:xsd="http://www.w3.org/2001/XMLSchema 
" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" SOAP- 
ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"><SOAP- 
ENV:Header></SOAP-ENV:Header><SOAP-ENV:Body><Hello><lastname  
id="o1454e20" xsi:type="xsd:string">Duerr</lastname><number  
id="o803588" xsi:type="xsd:int">1</number><first id="o1454de0"  
xsi:type="xsd:string">Jenn</first></Hello></SOAP-ENV:Body></SOAP- 
ENV:Envelope>
_________________________________ Tue May 13 23:11:03 2008 RESPONSE:
501
Not Implemented
-------
Date: Wed, 14 May 2008 06:11:03 GMT
Content-Type: text/html; charset=UTF-8
Server: gws
Content-Length: 1343
Connection: Close

Wolfram Services

I have dowloaded/installed the following with no errors:
  Python 2.6
  ZSI-2.0
  MingGW-5.1.4
  PyXML-0.8.4

I am running on a PC.

When running the following python code (from ZSI users guide) I get the 
following errors.

Thanks for your HELP

import sys
import timing
from ZSI.generate.commands import wsdl2py

#Connect and build the python files based on wsdl url
#wsdlurl = 
'http://webservices.wolfram.com/services/SearchServices/WolframSearch2.wsdl'
#args = ['-bu', wsdlurl]
#wsdl2py(args)

# import the generated class stubs
from WolframSearchService_services import *
# get a port proxy instance
loc = WolframSearchServiceLocator()
port = loc.getWolframSearchmyPortType()
# create a new request
req = WolframSearchRequest()
req.Options = req.new_Options()
req.Options.Query = 'newton'
# call the remote method
resp = port.WolframSearch(req)    <==== ERROR OCCURS HERE
# print results
print 'Search Time:', resp.Result.SearchTime
print 'Total Matches:', resp.Result.TotalMatches
for hit in resp.Result.Matches.Item:
print hit.Title

---------------------------------------------------------------------------
HERE IS THE ERRORS....

Web Service Access!!

Traceback (most recent call last):

File 
"C:\eclipse\workspace\TestCtsWebService\src\root\examples\wsTestWolframeSearch.py", 
line 30, in <module>

resp = port.WolframSearch(req)

File 
"C:\eclipse\workspace\TestCtsWebService\src\root\examples\WolframSearchService_services.py", 
line 105, in WolframSearch

response = self.binding.Receive(WolframSearchResponse.typecode)

File "C:\Python26\lib\site-packages\ZSI\client.py", line 498, in Receive

self.ReceiveSOAP(**kw)

File "C:\Python26\lib\site-packages\ZSI\client.py", line 398, in ReceiveSOAP

encodingStyle=kw.get('encodingStyle'))

File "C:\Python26\Lib\site-packages\ZSI\parse.py", line 54, in __init__

from xml.dom.ext.reader import PyExpat

ImportError: No module named ext.reader

> from xml.dom.ext.reader import PyExpat
>
> ImportError: No module named ext.reader

The Expat parser is included in Python 2.6 by default and is available
via xml.parsers.expat. ZSI will probably have to be updated to reflect
this -- perhaps it already has been? I would try ZSI 2.1a1 and then
ask again if the problem persists there

wsdl2py

Hi,

I'm having an issue with a type I have defined for my response in my wsdl.

One of the elements in my response is an xsd:list, which is just a list of strings seperated by space.
Here is the definition of the element:

<xsd:element name="linkedapplications" type="tnsb:linkedApplicationsList"/>

<xsd:simpleType name="linkedApplicationsList">
        <xsd:annotation>
            <xsd:documentation></xsd:documentation>
        </xsd:annotation>
        <xsd:list>
            <xsd:simpleType>
                <xsd:restriction base="xsd:string"></xsd:restriction>
            </xsd:simpleType>
        </xsd:list>
</xsd:simpleType>


I then run:
wsdl2py -b file.wsdl

And it auto generates my stubs.

Then testing the service it works fine if the <linkedapplications> element is empty.
But if it contains any values, such as <linkedapplications>value1</linkedapplications> or <linkedapplications>value1 value2</linkedapplications>

It throws the following error:

Traceback (most recent call last):
    resp = port.registerUserOrAddToGroup(req)
  File "generatedServices_client.py", line 41, in registerUserOrAddToGroup
    response = self.binding.Receive(registerUserOrAddToGroupResponse.typecode)
  File "build/bdist.cygwin-1.5.25-i686/egg/ZSI/client.py", line 536, in Receive
    return _Binding.Receive(self, replytype, **kw)
  File "build/bdist.cygwin-1.5.25-i686/egg/ZSI/client.py", line 461, in Receive
    reply = self.ps.Parse(tc)
  File "build/bdist.cygwin-1.5.25-i686/egg/ZSI/parse.py", line 326, in Parse
    return how.parse(self.body_root, self)
  File "build/bdist.cygwin-1.5.25-i686/egg/ZSI/TCcompound.py", line 196, in parse
    value = what.parse(c_elt, ps)
  File "build/bdist.cygwin-1.5.25-i686/egg/ZSI/TC.py", line 1672, in parse
    return self.text_to_data(v, elt, ps)
  File "build/bdist.cygwin-1.5.25-i686/egg/ZSI/TC.py", line 1643, in text_to_data
    v.append(self.itemTypeCode.text_to_data(item, elt, ps))
AttributeError: 'NoneType' object has no attribute 'text_to_data'


Is the definition of xsd:list allowed to by empty or do I have to specify enumerations?
I have seen examples that allow non enumerated xsd:list types.

Any help would be appreciated.

Cheers,
Jaie

Difference between revisions of "ZSI Notes"