了解twisted时遇到的问题

Twisted安装:

Pip install twisted

显示

Requirement already satisfied: twisted in e:\python\lib\site-packages

但是编译过程中

ImportError: No module named twisted.internet

在python环境下使用 help(‘modules’) 能够看到twisted模块
尝试卸载该模块 pip uninstall twisted 后用pip重新安装，成功。

callWhenRunning：reactor.callWhenRunning(a = fibonacci(1,1,99))

这个语句出现错误

TypeError: callWhenRunning() takes at least 2 arguments (1 given)

去掉赋值语句，通过函数内部赋值
错误：

AssertionError: 573147844013817084101 is not callable

去掉递归语句
错误：

AssertionError: None is not callable

检查发现函数引用不应有()
重新测试成功
用于测试的递归函数(计算斐波那契数列)：

def fibonacci(a,b,n):    if n:        return fibonacci(b,a+b,n-1)    else:            return b

通过traceback观察Twisted调用：

File “test.py”, line 14, in
reactor.run() File “E:\python\lib\site-packages\twisted\internet\base.py”, line 1242, in
run
self.startRunning(installSignalHandlers=installSignalHandlers) File “E:\python\lib\site-packages\twisted\internet\base.py”, line
1222, in startRunning
ReactorBase.startRunning(self) File “E:\python\lib\site-packages\twisted\internet\base.py”, line 735, in
startRunning
self.fireSystemEvent(‘startup’) File “E:\python\lib\site-packages\twisted\internet\base.py”, line 686, in
fireSystemEvent
event.fireEvent() File “E:\python\lib\site-packages\twisted\internet\base.py”, line 428, in
fireEvent
DeferredList(beforeResults).addCallback(self._continueFiring) File “E:\python\lib\site-packages\twisted\internet\defer.py”, line
321, in addCallback
callbackKeywords=kw) File “E:\python\lib\site-packages\twisted\internet\defer.py”, line 310, in
addCallbacks
self._runCallbacks() File “E:\python\lib\site-packages\twisted\internet\defer.py”, line 653, in
_runCallbacks
current.result = callback(current.result, *args, **kw) File “E:\python\lib\site-packages\twisted\internet\base.py”, line 441, in
_continueFiring
callable(*args, **kwargs) File “test.py”, line 11, in ask traceback.print_stack()

stop()：
通过在程序内部使用reactor.stop()终止

addReader(self)：
创建一个socket连接后，通过reactor.addReader(self)将自己传递给reactor

ClientFactory和Protocol:
ClientFactory的工作是管理连接事件，Protocol对象处理为一个成功的连接。一旦连接建立，Protocol就接管下面的工作，包括收发数据和决定是否关闭连接。

当编写一个启动非同步操作的函数时，返回一个Deferred对象。当操作完成时，调用Deferred的callback方法来返回值。如果操作失败，调用Deferred.errback函数来跑出异常。

临时文件下载网页：

downloadToTempFile(url).addCallback(printFile).addErrback(printError)reactor.run()def downloadToTempFile(url):    tmpfd,tempfilename = tempfile.mkstemp()    os.close(tmpfd)    return client.downloadPage(url,tempfilename).addCallback(returnFilename,tempfilename)

实现一个简单的http服务器:

from twisted.web import httpclass MyHttpFactory(http.HTTPFactory):    protocal = MyHttpclass MyHttp(http.HTTPChannel):    requestFactory = MyRequestHandlerclass MyRequestHandler(http.Request):    pages = {        '/':'<h1>Home</h1>Home Page',        '/test':'<h1>Test</h1>Test Page',        }    def process(self):        if self.pages.has_key(self.path):            self.write(self.pages[self.path])        else:            self.setResponseCode(http.NOT_FOUND)            self.write("<h1>Not Found</h1>Sorry,no such page.")        self.finish()if __name__ == '__main__':    from twisted.internet import reactor    reactor.listenTCP(8000,MyHttpFactory())    reactor.run()

出现错误代码：

NameError: name ‘MyHttp’ is not defined

调整类声明顺序
再次测试，在浏览器输入地址http://127.0.0.1:8080/无响应
检查浏览器network，发现tcp连接成功但服务器无响应
测试发现回调异常
查阅文档后暂定为版本问题，搁置