Simplify the API.

rfc6266.py

@@ -2,8 +2,11 @@
 
 """Implements RFC 6266, the Content-Disposition HTTP header.
 
-ContentDisposition handles the receiver side,
-header_for_filename handles the sender side.
+parse_headers (and variant parse_httplib2_response) handles the receiver side.
+It returns a ContentDisposition object with attributes like is_inline,
+filename_unsafe, filename_sanitized.
+
+build_header handles the sender side.
 """
 
 from lepl import *
@@ -15,7 +18,12 @@ import os.path
 import re
 
 
-__all__ = ('ContentDisposition', 'header_for_filename', )
+__all__ = (
+    'ContentDisposition',
+    'parse_headers',
+    'parse_httplib2_response',
+    'build_header',
+)
 
 
 LangTagged = namedtuple('LangTagged', 'string langtag')
@@ -33,8 +41,8 @@ class ContentDisposition(object):
     def __init__(self, disposition='inline', assocs=None, location=None):
         """This constructor is used internally after parsing the header.
 
-        Instances should generally be created from a factory class
-        method, such as from_headers and from_httplib2_response.
+        Instances should generally be created from a factory
+        function, such as parse_headers and parse_httplib2_response.
         """
 
         self.disposition = disposition
@@ -122,13 +130,13 @@ class ContentDisposition(object):
         return 'ContentDisposition(%r, %r, %r)' % (
             self.disposition, self.assocs, self.location)
 
-    @classmethod
-    def from_headers(cls, content_disposition, location=None):
+
+def parse_headers(content_disposition, location=None):
     """Build a ContentDisposition from header values.
     """
 
     if content_disposition is None:
-            return cls(location=location)
+        return ContentDisposition(location=location)
 
     # Both alternatives seem valid.
     if False:
@@ -144,6 +152,7 @@ class ContentDisposition(object):
         # in the filename parameter. But it does mean we occasionally
         # give less-than-certain values for some legacy senders.
         content_disposition = content_disposition.encode('iso-8859-1')
+
     # Check the caller already did LWS-folding (normally done
     # when separating header names and values; RFC 2616 section 2.2
     # says it should be done before interpretation at any rate).
@@ -155,16 +164,17 @@ class ContentDisposition(object):
     # However http doesn't allow isolated CR and LF in headers outside
     # of LWS.
     assert is_lws_safe(content_disposition)
+
     parsed = content_disposition_value.parse(content_disposition)
     return ContentDisposition(
         disposition=parsed[0], assocs=parsed[1:], location=location)
 
-    @classmethod
-    def from_httplib2_response(cls, response):
+
+def parse_httplib2_response(response):
     """Build a ContentDisposition from an httplib2 response.
     """
 
-        return cls.from_headers(
+    return parse_headers(
         response['content-disposition'], response['content-location'])
 
 
@@ -298,7 +308,7 @@ def qd_quote(text):
     return text.replace('\\', '\\\\').replace('"', '\\"')
 
 
-def header_for_filename(
+def build_header(
     filename, disposition='attachment', filename_compat=None
 ):
     """Generate a Content-Disposition header for a given filename.
@@ -357,17 +367,17 @@ def header_for_filename(
 
 
 def test_parsing():
-    cdfh = ContentDisposition.from_headers
-    assert ContentDisposition().disposition == 'inline'
-    assert cdfh('attachment').disposition == 'attachment'
-    assert cdfh('attachment; key=val').assocs['key'] == 'val'
-    assert cdfh('attachment; filename=simple').filename_unsafe == 'simple'
+    assert parse_headers(None).disposition == 'inline'
+    assert parse_headers('attachment').disposition == 'attachment'
+    assert parse_headers('attachment; key=val').assocs['key'] == 'val'
+    assert parse_headers(
+        'attachment; filename=simple').filename_unsafe == 'simple'
 
     # test ISO-8859-1
-    fname = cdfh(u'attachment; filename="oyé"').filename_unsafe
+    fname = parse_headers(u'attachment; filename="oyé"').filename_unsafe
     assert fname == u'oyé', repr(fname)
 
-    cd = cdfh(
+    cd = parse_headers(
         'attachment; filename="EURO rates";'
         ' filename*=utf-8\'\'%e2%82%ac%20rates')
     assert cd.filename_unsafe == u'€ rates'
@@ -375,8 +385,7 @@ def test_parsing():
 
 def test_roundtrip():
     def roundtrip(filename):
-        return ContentDisposition.from_headers(
-            header_for_filename(filename)).filename_unsafe
+        return parse_headers(build_header(filename)).filename_unsafe
 
     def assert_roundtrip(filename):
         assert roundtrip(filename) == filename