# HG changeset patch
# User paulb
# Date 1094382752 0
# Node ID fcf7098ad0d2588aa32978e4c91dd78f7a8a3991
# Parent  eda1b744eec096b31bfcd729cf4f8aec1233599c
[project @ 2004-09-05 11:12:32 by paulb]
Introduced a general HeaderValue class, changed ContentType to be a
subclass of this new class, added a parse_header_value method.
Modified the JavaServlet module to use the parse_header_value method when
inspecting multipart/form-data requests.

diff -r eda1b744eec0 -r fcf7098ad0d2 WebStack/Generic.py
--- a/WebStack/Generic.py	Fri Sep 03 21:35:54 2004 +0000
+++ b/WebStack/Generic.py	Sun Sep 05 11:12:32 2004 +0000
@@ -15,7 +15,46 @@
 directors.
 """
 
-class ContentType:
+class HeaderValue:
+
+    "A container for header information."
+
+    def __init__(self, principal_value, **attributes):
+
+        """
+        Initialise the container with the given 'principal_value' and optional
+        keyword attributes representing the key=value pairs which accompany the
+        'principal_value'.
+        """
+
+        self.principal_value = principal_value
+        self.attributes = attributes
+
+    def __getattr__(self, name):
+        if self.attributes.has_key(name):
+            return self.attributes[name]
+        else:
+            raise AttributeError, name
+
+    def __str__(self):
+
+        """
+        Format the header value object, producing a string suitable for the
+        response header field.
+        """
+
+        l = []
+        if self.principal_value:
+            l.append(self.principal_value)
+            for name, value in self.attributes.items():
+                l.append("; ")
+                l.append("%s=%s" % (name, value))
+
+        # Make sure that only ASCII is used.
+
+        return "".join(l).encode("US-ASCII")
+
+class ContentType(HeaderValue):
 
     "A container for content type information."
 
@@ -27,30 +66,19 @@
         pairs which qualify content types.
         """
 
-        self.media_type = media_type
-        self.charset = charset
-        self.attributes = attributes
-
-    def __str__(self):
-
-        """
-        Format the content type object, producing a string suitable for the
-        response header field.
-        """
+        if charset is not None:
+            attributes["charset"] = charset
+        HeaderValue.__init__(self, media_type, **attributes)
 
-        l = []
-        if self.media_type:
-            l.append(self.media_type)
-            if self.charset:
-                l.append("; ")
-                l.append("charset=%s" % self.charset)
-            for name, value in self.attributes.items():
-                l.append("; ")
-                l.append("%s=%s" % (name, value))
-
-        # Make sure that only ASCII is used.
-
-        return "".join(l).encode("US-ASCII")
+    def __getattr__(self, name):
+        if name == "media_type":
+            return self.principal_value
+        elif name == "charset":
+            return self.attributes.get("charset")
+        elif self.attributes.has_key(name):
+            return self.attributes[name]
+        else:
+            raise AttributeError, name
 
 class Transaction:
 
@@ -74,34 +102,34 @@
 
     # Utility methods.
 
-    def parse_content_type(self, content_type_field):
+    def parse_header_value(self, header_class, header_value_str):
 
         """
-        Determine the content type and charset from the supplied
-        'content_type_field' string.
+        Create an object of the given 'header_class' by determining the details
+        of the given 'header_value_str' - a string containing the value of a
+        particular header.
         """
 
-        if content_type_field is None:
-            return ContentType(None)
+        if header_value_str is None:
+            return header_class(None)
 
-        l = content_type_field.split(";")
+        l = header_value_str.split(";")
         attributes = {}
-        charset = None
 
-        # Find the charset and remember all other attributes.
+        # Find the attributes.
 
-        media_type, attributes_str = l[0].strip(), l[1:]
+        principal_value, attributes_str = l[0].strip(), l[1:]
 
         for attribute_str in attributes_str:
             t = attribute_str.split("=")
             if len(t) > 1:
                 name, value = t[0].strip(), t[1].strip()
-                if name == "charset":
-                    charset = value
-                else:
-                    attributes[name] = value
+                attributes[name] = value
 
-        return ContentType(media_type, charset, **attributes)
+        return header_class(principal_value, **attributes)
+
+    def parse_content_type(self, content_type_field):
+        return self.parse_header_value(ContentType, content_type_field)
 
     def format_header_value(self, value):
 
diff -r eda1b744eec0 -r fcf7098ad0d2 WebStack/JavaServlet.py
--- a/WebStack/JavaServlet.py	Fri Sep 03 21:35:54 2004 +0000
+++ b/WebStack/JavaServlet.py	Sun Sep 05 11:12:32 2004 +0000
@@ -15,6 +15,7 @@
 import javax.mail.Session
 import java.util.Properties
 import java.net.URLDecoder
+from WebStack.Generic import HeaderValue
 
 class Stream:
 
@@ -511,15 +512,14 @@
 
                 # Should get: form-data; name="x"
 
-                disposition = part.getHeader("Content-Disposition")[0]
-                name = self._get_header_attribute(disposition, "name")
+                disposition = self.parse_header_value(HeaderValue, part.getHeader("Content-Disposition")[0])
 
                 # Store and optionally convert the field.
 
-                if name is not None:
-                    if not fields.has_key(name):
-                        fields[name] = []
-                    fields[name].append(subcontent)
+                if disposition.name is not None:
+                    if not fields.has_key(disposition.name[1:-1]):
+                        fields[disposition.name[1:-1]] = []
+                    fields[disposition.name[1:-1]].append(subcontent)
 
             # Otherwise, descend deeper into the multipart hierarchy.
 
@@ -528,15 +528,6 @@
 
         return fields
 
-    def _get_header_attribute(self, header_value, attribute_name):
-        parts = header_value.split(";")
-        if len(parts) > 1:
-            for attribute in parts[1:]:
-                t = attribute.split("=")
-                if len(t) == 2 and t[0].strip() == attribute_name:
-                    return t[1].strip()[1:-1]
-        return None
-
 class Session:
 
     """