Improved highlighting of HTTP headers.

Closes #60.

README.rst

@@ -184,7 +184,7 @@ See ``http -h`` for more details::
       ITEM                  A key-value pair whose type is defined by the
                             separator used. It can be an HTTP header
                             (header:value), a query parameter (name=:value),
-                            a data field to be used in the request body 
+                            a data field to be used in the request body
                             (field_name=value), a raw JSON data field
                             (field_name:=value), or a file field
                             (field_name@/path/to/file). You can use a backslash to
@@ -280,6 +280,7 @@ Changelog
 ---------
 
 * `0.2.6dev <https://github.com/jkbr/httpie/compare/0.2.5...master>`_
+    * Improved highlighing of HTTP headers.
     * Added query string parameters (param=:value).
     * Added support for terminal colors under Windows.
 * `0.2.5 <https://github.com/jkbr/httpie/compare/0.2.2...0.2.5>`_ (2012-07-17)

httpie/pretty.py

@@ -1,52 +1,110 @@
+"""
+Colorizing of HTTP messages and content processing.
+
+"""
 import os
 import re
 import json
-
 import pygments
-
-from pygments.util import ClassNotFound
+from pygments import token, lexer
 from pygments.styles import get_style_by_name, STYLE_MAP
-from pygments.lexers import get_lexer_for_mimetype, HttpLexer
-from pygments.formatters.terminal256 import Terminal256Formatter
+from pygments.lexers import get_lexer_for_mimetype
 from pygments.formatters.terminal import TerminalFormatter
+from pygments.formatters.terminal256 import Terminal256Formatter
+from pygments.util import ClassNotFound
 from requests.compat import is_windows
 from . import solarized
 
+
+DEFAULT_STYLE = 'solarized'
+AVAILABLE_STYLES = [DEFAULT_STYLE] + list(STYLE_MAP.keys())
 if is_windows:
     import colorama
     colorama.init()
     # 256 looks better on Windows
-    FORMATTER = Terminal256Formatter
+    formatter_class = Terminal256Formatter
 else:
-    FORMATTER = (
+    formatter_class = (
         Terminal256Formatter
         if '256color' in os.environ.get('TERM', '')
         else TerminalFormatter
     )
 
 
-DEFAULT_STYLE = 'solarized'
-AVAILABLE_STYLES = [DEFAULT_STYLE] + list(STYLE_MAP.keys())
+class HTTPLexer(lexer.RegexLexer):
+    """
+    Simplified HTTP lexer for Pygments.
 
-application_content_type_re = re.compile(r'application/(.+\+)(json|xml)$')
+    It only operates on headers and provides a stronger contrast between
+    their names and values than the original one bundled with Pygments
+    (`pygments.lexers.text import HttpLexer`), especially when
+    Solarized color scheme is used.
+
+    """
+    name = 'HTTP'
+    aliases = ['http']
+    filenames = ['*.http']
+    tokens = {
+        'root': [
+
+            # Request-Line
+            (r'([A-Z]+)( +)([^ ]+)( +)(HTTP)(/)(\d+\.\d+)',
+             lexer.bygroups(
+                token.Name.Function,
+                token.Text,
+                token.Name.Namespace,
+                token.Text,
+                token.Keyword.Reserved,
+                token.Operator,
+                token.Number
+             )),
+
+            # Response Status-Line
+            (r'(HTTP)(/)(\d+\.\d+)( +)(\d{3})( +)(.+)',
+             lexer.bygroups(
+                 token.Keyword.Reserved,  # 'HTTP'
+                 token.Operator,  # '/'
+                 token.Number,  # Version
+                 token.Text,
+                 token.Number,  # Status code
+                 token.Text,
+                 token.Name.Exception,  # Reason
+             )),
+
+            # Header
+            (r'(.*?)( *)(:)( *)(.+)', lexer.bygroups(
+                token.Name.Attribute, # Name
+                token.Text,
+                token.Operator,  # Colon
+                token.Text,
+                token.String  # Value
+            ))
+    ]}
 
 
 class PrettyHttp(object):
+    """HTTP headers & body prettyfier."""
 
     def __init__(self, style_name):
-        if style_name == 'solarized':
-            style = solarized.SolarizedStyle
-        else:
+        try:
             style = get_style_by_name(style_name)
-        self.formatter = FORMATTER(style=style)
+        except ClassNotFound:
+            style = solarized.SolarizedStyle
+        self.formatter = formatter_class(style=style)
 
     def headers(self, content):
-        return pygments.highlight(content, HttpLexer(), self.formatter)
+        """Pygmentize HTTP headers."""
+        return pygments.highlight(content, HTTPLexer(), self.formatter)
 
     def body(self, content, content_type):
+        """Pygmentize `content` based on `content_type`."""
+
         content_type = content_type.split(';')[0]
-        application_match = re.match(application_content_type_re,
-                                     content_type)
+
+        application_match = re.match(
+            r'application/(.+\+)(json|xml)$',
+            content_type
+        )
         if application_match:
             # Strip vendor and extensions from Content-Type
             vendor, extension = application_match.groups()
@@ -57,13 +115,14 @@ class PrettyHttp(object):
         except ClassNotFound:
             return content
 
-        if content_type == "application/json":
+        if content_type == 'application/json':
             try:
                 # Indent and sort the JSON data.
                 content = json.dumps(json.loads(content),
                                      sort_keys=True, indent=4,
                                      ensure_ascii=False)
-            except:
+            except ValueError:
+                # Invalid JSON - we don't care.
                 pass
 
         return pygments.highlight(content, lexer, self.formatter)