Python Flask崩溃，ValueError:太多值无法解包

我有一个与另一个web服务通信的flask应用程序。我有一个错误，这似乎只发生在两个应用程序都在同一台服务器上运行时，但我不知道源代码是什么。Flask应用程序通过Apache中的

WSGIScriptAlias

托管在

/tools

上

[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114] mod_wsgi (pid=25705): Exception occurred processing WSGI script '/opt/tools-frontend/wsgi.py'.
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114] Traceback (most recent call last):
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]   File "/opt/tools-frontend/ENV_1/lib/python2.7/site-packages/flask/app.py", line 1701, in __call__
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]     return self.wsgi_app(environ, start_response)
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]   File "/opt/tools-frontend/ENV_1/lib/python2.7/site-packages/flask/app.py", line 1689, in wsgi_app
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]     response = self.make_response(self.handle_exception(e))
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]   File "/opt/tools-frontend/ENV_1/lib/python2.7/site-packages/flask/app.py", line 1687, in wsgi_app
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]     response = self.full_dispatch_request()
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]   File "/opt/tools-frontend/ENV_1/lib/python2.7/site-packages/flask/app.py", line 1361, in full_dispatch_request
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]     response = self.make_response(rv)
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]   File "/opt/tools-frontend/ENV_1/lib/python2.7/site-packages/flask/app.py", line 1447, in make_response
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]     rv = self.response_class(rv, headers=headers, status=status)
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]   File "/opt/tools-frontend/ENV_1/lib/python2.7/site-packages/werkzeug/wrappers.py", line 627, in __init__
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]     self.headers = Headers(headers)
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]   File "/opt/tools-frontend/ENV_1/lib/python2.7/site-packages/werkzeug/datastructures.py", line 836, in __init__
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]     self.extend(defaults)
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]   File "/opt/tools-frontend/ENV_1/lib/python2.7/site-packages/werkzeug/datastructures.py", line 978, in extend
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114]     for key, value in iterable:
[Thu May 23 13:11:44 2013] [error] [client 41.164.8.114] ValueError: too many values to unpack
[Thu May 23 13:11:44 2013] [debug] mod_deflate.c(615): [client 41.164.8.114] Zlib: Compressed 590 to 372 : URL /tools/api/login/, referer: http://www.website.com/tools

API托管在同一台计算机上的不同域中，查看日志文件，它工作正常

API调用在以下函数中进行：

@app.route('/api/', methods=['GET', 'POST', 'PUT', 'DELETE'])
@app.route('/api/<path:endpoint>', methods=['GET', 'POST', 'PUT', 'DELETE'])
def api(endpoint=None):
    # extract POST/PUT variables
    dat = request.form
    if len(dat) == 0:
        # extract GET variables
        dat = request.args
    # submit request to API
    out = call_api(request.method, endpoint, dat, request.files)
    return out

---

我最好的猜测是您返回了一个特殊的headers字典（来自python请求），而不是一个普通的字典。烧瓶采用两种形式的集管：

{'key': 'value'}
# and
[('key', 'value')]

由于您的特殊dict未被识别为真正的dict，因此它将被视为元组列表，而元组列表失败

改变

return r.text, r.status_code, r.headers

到

---

您正在尝试在视图中设置标题吗？你能分享代码吗？

headers

的值不是

None

，也不是dict，而是可编辑的。Iterable应该产生

（键，值）

对，但这不是它得到的。在我看来，崩溃发生在flask/werkzeug试图处理响应时。您可以在堆栈跟踪中看到，根本不涉及我的代码，顶部文件是

flask/app/py

。触发API调用的行是

r=requests.get（url，data=data，verify=False）

您可以共享您的视图代码吗？解析响应的标题会让人窒息，您的代码不在堆栈跟踪中，因为错误不在您的视图中是的，但这并不意味着它不是原因-它毕竟生成了响应。我不可能对此投足够的赞成票！你解决了一周的痛苦和挫折。

return r.text, r.status_code, r.headers

return r.text, r.status_code, r.headers.items()