In Python, are there any libraries that mock out responses for httplib?

Question

I'm currently using python_flickr_api to upload photos for my app: it uses httplib to perform a multipart POST request.

Problem: I want to verify that the upload really is issued in an integration test by intercepting the POST request and creating a pre-canned success response so that my tests can run completely offline and not depend on Flickr (I don't want to upload the same test image 100 times, either!)

To this end, I've tried using two incredible libraries: VCRPy and HTTPretty. Neither of them solves my problem because neither of them support httplib (HTTPretty comes closest, with support for httplib2 only), and I get an error that looks something like this:

 Failure/Error: [Errno 32] Broken pipe

 Traceback:
 ...
 File "/usr/local/lib/python2.7/site-packages/flickr_api/upload.py", line 92, in upload
     r = post(UPLOAD_URL,auth.AUTH_HANDLER,args,photo_file)
 File "/usr/local/lib/python2.7/site-packages/flickr_api/upload.py", line 52, in post
     r = multipart.posturl(url,fields,files)
 File "/usr/local/lib/python2.7/site-packages/flickr_api/multipart.py", line 19, in posturl
     return post_multipart(urlparts[1], urlparts[2], fields,files)
 File "/usr/local/lib/python2.7/site-packages/flickr_api/multipart.py", line 33, in post_multipart
     h.send(body)
 File "/usr/local/Cellar/python/2.7.5/Frameworks/Python.framework/Versions/2.7/lib/python2.7/httplib.py", line 805, in send
     self.sock.sendall(data)
 File "/usr/local/lib/python2.7/site-packages/httpretty/core.py", line 243, in sendall
     return self._true_sendall(data)
 File "/usr/local/lib/python2.7/site-packages/httpretty/core.py", line 216, in _true_sendall
     self.truesock.sendall(data, *args, **kw)
 File "/usr/local/Cellar/python/2.7.5/Frameworks/Python.framework/Versions/2.7/lib/python2.7/socket.py", line 224, in meth
     return getattr(self._sock,name)(*args)

So clearly httpretty is intercepting but is causing a broken pipe.

How can I fix this?

Answer 1

There are tons of libraries for this type of functionality, checkout Mock

But it looks like your are looking for something similar to FakeWeb so I would checkout HTTPretty

Seeing as you have already tried HTTPretty. I would mock out the method call that flickr_api makes and have it return a stub that has the payload you are expecting.

Goodluck.

Answer 2

Why don't you write a simple WSGI server which prints what you need to?

For example, the following code (using only the Python Standard Library):

def application(environ, start_response):
    print environ
    status = "200 OK"
    headers = [("Content-Type", "text/plain"),
               ("Content-Length", "0")]
    start_response(status, headers)
    return ""

if __name__ == "__main__":
    from wsgiref.simple_server import make_server
    httpd = make_server("localhost", 8080, application)
    httpd.serve_forever()

will print to the screen the environment of the request (stuff like request method, url, etc). You can also very simply print the request body, etc.

In your flickr application, simply replace the URL by localhost:8080 and make the requests to your own computer.

Answer 3

I'm the author of VCR.py. I think I may have fixed the bug preventing VCR from working with the flickr API library you're using. Try installing the version in the fix-flickr-api branch and let me know if that works for you.