twisted-suds的好處 - 使用python suds soap lib的異步方式

Question

我正在使用python suds庫來創建基於本地wsdl文件的SOAP客戶端。 我的目標是使用Twisted作為后端，因此我以異步方式查詢SOAP服務器。

我知道這個主題已被覆蓋不同的時間（ here1 ， here2 ），但我仍然有一些問題。

---

我已經看到三種不同的方法來使用與肥皂混合：

a）將此補丁應用於suds庫。

b）使用tw-suds ，這是肥皂水。

c）受到這篇文章的影響，我使用twisted deferToThread操作實現了Client_Async客戶端（可以在這里找到完全工作的gist。我還實現了Client_Sync客戶端以做一些基准測試）

# Init approach c) code
from suds.client import Client as SudsClient
from twisted.internet.threads import deferToThread

class MyClient(SudsClient):
   def handleFailure(self, f, key, stats):
        stats.stop_stamp(error=True)
        logging.error("%s. Failure: %s" % (key, str(f)))

    def handleResult(self, result, key, stats):
        stats.stop_stamp(error=False)
        success, text, res = False, None, None
        try:
            success = result.MessageResult.MessageResultCode == 200
            text = result.MessageResult.MessageResultText
            res = result.FooBar
        except Exception, err:
            pass
        logging.debug('%40s : %5s %10s \"%40s\"' % (key, success, text, res))
        logging.debug('%40s : %s' % (key, self.last_sent()))
        logging.debug('%40s : %s' % (key, self.last_received()))

def call(stats, method, service, key, *a, **kw):
    stats.start_stamp()
    logging.debug('%40s : calling!' % (key))
    result = service.__getattr__(method)(*a, **kw)
    return result

class Client_Async(MyClient):
    """ Twisted based async client"""
    def callRemote(self, stats, method, key, *args, **kwargs):
        logging.debug('%s. deferring to thread...' % key)
        d = deferToThread(call, stats, method, self.service, key, *args, **kwargs)
        d.addCallback(self.handleResult, key, stats)
        d.addErrback(self.handleFailure, key, stats)
        return d

class Client_Sync(MyClient):
    def callRemote(self, stats,  method, key, *args, **kwargs):
        result = None
        try:
            result = call(stats, method, self.service, key, *args, **kwargs)
        except Exception, err:
            self.handleFailure(err, key, stats)
        else:
            self.handleResult(result, key, stats)
# End approach c) code

---

使用c）方法做一個小基准測試指出了Async模型的好處：

-- Sync model using Client_Sync of approach c).
# python soap_suds_client.py -t 200 --sync
Total requests:800/800. Success:794 Errors:6
Seconds elapsed:482.0
Threads used:1

-- Async model using Client_Async of approach c).
# python soap_suds_client.py -t 200
Total requests:800/800. Success:790 Errors:10
Seconds elapsed:53.0
Threads used:11

我沒有測試方法a）或b），我的問題是：

除了使用一個線程之外，我真正從中獲得了什么？

Answer 1

我在我的項目中使用肥皂水。 我沒有做任何補丁，也沒有使用過扭曲的泡沫。 我正在使用0.4.1-2版本的python-suds包（在ubuntu上），它帶有非常有用的nosend選項。

    # This parses the wsdl file. The autoblend option you'd probably skip, 
    # its needed when name spaces are not strictly preserved (case for Echo Sign).
    from suds import client
    self._suds = client.Client('file://' + config.wsdl_path, nosend=True,
                               autoblend=True)

    ....

    # Create a context for the call, example sendDocument() call. This doesn't yet
    # send anything, only creates an object with the request and capable of parsing
    # the response
    context = self._suds.service.sendDocument(apiKey=....)

    # Actually send the request. Use any web client you want. I actually use 
    # something more sophisticated, but below I put the example using 
    # standard twisted web client.
    from twisted.web import client
    d = client.getPage(url=context.client.location(), 
                       postdata=str(context.envelope),
                       method='POST',
                       headers=context.client.headers())

    # The callback() of the above Deferred is fired with the body of the 
    # http response. I parse it using the context object.          
    d.addCallback(context.succeeded)

    # Now in the callback you have the actual python object defined in 
    # your WSDL file. You can print...
    from pprint import pprint
    d.addCallback(pprint)
    # I the response is a failure, your Deferred would be errbacked with 
    # the suds.WebFault exception.