如何发出 GET 请求，然后使用 Python (Twisted) 打印出响应正文

Question

在 Twisted 的网站上，他们有一个名为“接收响应”的示例，该示例向您展示了如何获取响应标头和响应代码等，但不包括响应正文（向网站的请求返回的实际 HTML 正文） .

在 def cbrequest(response) 中，我如何打印出 GET 请求返回给 example.com 的 HTML 文本？他们展示了诸如 response.headers 之类的方法来获取标题，但我还没有看到返回前端正文的方法。

我尝试打印 response.deliverBody(BeginningPrinter(finished)) 以获取响应文本，但无济于事

http://twistedmatrix.com/documents/12.1.0/web/howto/client.html#auto9

from pprint import pformat

from twisted.internet import reactor
from twisted.internet.defer import Deferred
from twisted.internet.protocol import Protocol
from twisted.web.client import Agent
from twisted.web.http_headers import Headers

class BeginningPrinter(Protocol):
    def __init__(self, finished):
        self.finished = finished
        self.remaining = 1024 * 10

    def dataReceived(self, bytes):
        if self.remaining:
            display = bytes[:self.remaining]
            print 'Some data received:'
        print display
        self.remaining -= len(display)

 def connectionLost(self, reason):
    print 'Finished receiving body:', reason.getErrorMessage()
    self.finished.callback(None)

agent = Agent(reactor)
d = agent.request(
    'GET',
    'http://example.com/',
    Headers({'User-Agent': ['Twisted Web Client Example']}),
    None)

def cbRequest(response):
    print 'Response version:', response.version
    print 'Response code:', response.code
    print 'Response phrase:', response.phrase
    print 'Response headers:'
    print pformat(list(response.headers.getAllRawHeaders()))
    finished = Deferred()
    response.deliverBody(BeginningPrinter(finished))
    return finished
d.addCallback(cbRequest)

def cbShutdown(ignored):
   reactor.stop()
d.addBoth(cbShutdown)

reactor.run()

Answer 1

您必须保留数据并在之后返回

class BeginningPrinter(Protocol):
    def __init__(self, finished):
        self.finished = finished
        self.remaining = 1024 * 10
        self.buff = None

    def dataReceived(self, bytes):
        if self.buff is None:
            self.buff = bytes
        else:
            self.buff += bytes
        if self.remaining:
            display = bytes[:self.remaining]
            print 'Some data received:'
        print display
        self.remaining -= len(display)

    def connectionLost(self, reason):
        print 'Finished receiving body:', reason.getErrorMessage()
        self.finished.callback(self.buff)

请注意，您可能应该删除变量 remaining，因为此代码示例期望服务器以 1024 * 10 字节响应。

class BeginningPrinter(Protocol):
    def __init__(self, finished):
        self.finished = finished
        self.buff = None

    def dataReceived(self, bytes):
        if self.buff is None:
            self.buff = bytes
        else:
            self.buff += bytes

    def connectionLost(self, reason):
        print 'Finished receiving body:', reason.getErrorMessage()
        self.finished.callback(self.buff)