import itertools import mimetools import mimetypes __all__ = ['MultiPartForm'] 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.""" if isinstance(name, unicode): name = name.encode('utf-8') if isinstance(value, unicode): value = value.encode('utf-8') self.form_fields.append((name, value)) return def add_file(self, fieldname, filename, fileHandle, mimetype=None): """Add a file to be uploaded.""" if isinstance(fieldname, unicode): fieldname = fieldname.encode('utf-8') if isinstance(filename, unicode): filename = filename.encode('utf-8') if hasattr(fileHandle, 'read'): body = fileHandle.read() else: body = fileHandle 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)