python - 属性错误 : 'str' object has no attribute 'items'

Question

在下面的代码中:

#!/usr/local/bin/python
import json

APPLICATION_NAME = 'cc9226315643df89-36bf02429075329d0ba36748360d050c'

HEADERS1 = json.dumps(dict(Destination = u"/api/af/latest/applications/%s/rulesets" % (APPLICATION_NAME)))
print "Headers1 is %s" % (HEADERS1)
HEADERS2 = {'Destination': '/api/af/latest/applications/%s/rulesets' % (APPLICATION_NAME)}
print "Headers2 is %s" % (HEADERS2)

我得到以下输出:

Headers1 is {"Destination": "/api/af/latest/applications/cc9226315643df89-36bf02429075329d0ba36748360d050c/rulesets"}
Headers2 is {'Destination': '/api/af/latest/applications/cc9226315643df89-36bf02429075329d0ba36748360d050c/rulesets'}

但是当我尝试在使用 requests() 的 REST 调用中使用 HEADER1 或 HEADER2 时，我得到非常不同的结果:

SERVER_URL = 'http://1.1.33.109:8087%s' % (APP_PATH)
REQ_DATA = None
print "Headers are: ", HEADERS
print "SERVER_URL is: ", SERVER_URL
print "Request Data is:", REQ_DATA
print ""

RESPONSE = requests.request(
    'MOVE', 
    SERVER_URL, 
    auth = ('admin', 'admin'), 
    verify = False, 
    data = REQ_DATA,
    headers = HEADERS1 )     #<-- If I use HEADER1 it breaks, if I use HEADER2 it works
print "Move Ruleset back to the Application RESULT: %s\n" % (RESPONSE)

我通过 HEADER1 得到以下内容:

Traceback (most recent call last):
   File "./myrest.py", line 234, in <module>
     headers = HEADERS1 )
   File "/usr/local/Cellar/python/2.7.5/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/requests/api.py", line 44, in request
     return session.request(method=method, url=url, **kwargs)
   File "/usr/local/Cellar/python/2.7.5/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/requests/sessions.py", line 324, in request
     prep = req.prepare()
   File "/usr/local/Cellar/python/2.7.5/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/requests/models.py", line 223, in prepare
     p.prepare_headers(self.headers)
   File "/usr/local/Cellar/python/2.7.5/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/requests/models.py", line 340, in prepare_headers
     headers = dict((name.encode('ascii'), value) for name, value in headers.items())
AttributeError: 'str' object has no attribute 'items'

如果我使用 HEADER2，它会干净地执行:

Move Ruleset back to the Application RESULT: Response [200]

谁能解释一下有什么区别？

Answer 1

您正在传递一个字符串； headers 不能永远是一个 JSON 编码的字符串，它总是一个 Python 字典。

print 结果具有欺骗性； JSON 编码的对象看起来很像 Python 字典表示，但它们远不是一回事。

requests API明确指出 headers 必须是一个字典:

• headers – (optional) Dictionary of HTTP Headers to send with the Request.

JSON 数据是您将作为内容发送到另一台服务器的数据，而不是您用来与 Python API 通信的数据。