HTTP helpers.

django_pyvows/http_helpers.py

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+import urllib2
+from urllib import urlencode
+
+import mimetypes
+import mimetools
+import itertools
+
+class MultiPartForm(object):
+    """Accumulate the data to be used when posting a form."""
+
+    def __init__(self):
+        self.form_fields = []
+        self.files = []
+        self.boundary = mimetools.choose_boundary()
+        return
+
+    def get_content_type(self):
+        return 'multipart/form-data; boundary=%s' % self.boundary
+
+    def add_field(self, name, value):
+        """Add a simple field to the form data."""
+        self.form_fields.append((name, value))
+        return
+
+    def add_file(self, fieldname, filename, fileHandle, mimetype=None):
+        """Add a file to be uploaded."""
+        body = fileHandle.read()
+        if mimetype is None:
+            mimetype = mimetypes.guess_type(filename)[0] or 'application/octet-stream'
+        self.files.append((fieldname, filename, mimetype, body))
+        return
+
+    def __str__(self):
+        """Return a string representing the form data, including attached files."""
+        # Build a list of lists, each containing "lines" of the
+        # request.  Each part is separated by a boundary string.
+        # Once the list is built, return a string where each
+        # line is separated by '\r\n'.
+        parts = []
+        part_boundary = '--' + self.boundary
+
+        # Add the form fields
+        parts.extend(
+            [ part_boundary,
+              'Content-Disposition: form-data; name="%s"' % name,
+              '',
+              value,
+            ]
+            for name, value in self.form_fields
+            )
+
+        # Add the files to upload
+        parts.extend(
+            [ part_boundary,
+              'Content-Disposition: file; name="%s"; filename="%s"' % \
+                 (field_name, filename),
+              'Content-Type: %s' % content_type,
+              '',
+              body,
+            ]
+            for field_name, filename, content_type, body in self.files
+            )
+
+        # Flatten the list and add closing boundary marker,
+        # then return CR+LF separated data
+        flattened = list(itertools.chain(*parts))
+        flattened.append('--' + self.boundary + '--')
+        flattened.append('')
+        return '\r\n'.join(flattened)
+
+
+def get(url):
+    response = urllib2.urlopen(url)
+    return response
+
+def post(url, data):
+    form = MultiPartForm()
+
+    for field, value in data.iteritems():
+        if isinstance(value, basestring):
+            form.add_field(field, value)
+        else:
+            form.add_file(field, value.name, value)
+
+    request = urllib2.Request(url)
+    body = str(form)
+    request.add_header('Content-type', form.get_content_type())
+    request.add_header('Content-length', len(body))
+    request.add_data(body)
+
+    try:
+        response = urllib2.urlopen(request)
+    except urllib2.HTTPError, err:
+        response = err
+
+    return response
+