diff --git a/rules_python/whl.py b/rules_python/whl.py
index 3e9d4f88fa..46211f1173 100644
--- a/rules_python/whl.py
+++ b/rules_python/whl.py
@@ -14,12 +14,17 @@
 """The whl modules defines classes for interacting with Python packages."""
 
 import argparse
+import collections
+import rfc822
 import json
 import os
 import pkg_resources
 import re
 import zipfile
 
+EXTRA_RE = re.compile("""^(?P<package>.*?)(;\s*(?P<condition>.*?)(extra == '(?P<extra>.*?)')?)$""")
+MayRequiresKey = collections.namedtuple('MayRequiresKey', ('condition', 'extra'))
+
 
 class Wheel(object):
 
@@ -66,7 +71,7 @@ def metadata(self):
           pass
       # fall back to METADATA file (https://www.python.org/dev/peps/pep-0427/)
       with whl.open(self._dist_info() + '/METADATA') as f:
-        return self._parse_metadata(f.read().decode("utf-8"))
+        return self._parse_metadata(f)
 
   def name(self):
     return self.metadata().get('name')
@@ -107,9 +112,45 @@ def expand(self, directory):
 
   # _parse_metadata parses METADATA files according to https://www.python.org/dev/peps/pep-0314/
   def _parse_metadata(self, content):
-    # TODO: handle fields other than just name
-    name_pattern = re.compile('Name: (.*)')
-    return { 'name': name_pattern.search(content).group(1) }
+    def get_header_value(header):
+      return header.strip().split(':', 2)[1].strip()
+    metadata = {}
+    pkg_info = rfc822.Message(content)
+    metadata['name'] = pkg_info.get('Name')
+    extras = [get_header_value(h) for h in pkg_info.getallmatchingheaders('Provides-Extra')]
+    if extras:
+      metadata['extras'] = list(set(extras))
+
+    reqs_dist = [get_header_value(h) for h in pkg_info.getallmatchingheaders('Requires-Dist')]
+    requires = collections.defaultdict(set)
+    for value in sorted(reqs_dist):
+      extra_match = EXTRA_RE.search(value)
+      if extra_match:
+        groupdict = extra_match.groupdict()
+        condition = groupdict['condition']
+        extra = groupdict['extra']
+        package = groupdict['package']
+        if condition.endswith(' and '):
+          condition = condition[:-5]
+      else:
+        condition, extra = None, None
+        package = value
+      key = MayRequiresKey(condition, extra)
+      requires[key].add(package)
+
+    if requires:
+      metadata['run_requires'] = []
+      for key, value in requires.items():
+        requirement = {
+          'requires': list(value)
+        }
+        if key.extra:
+          requirement['extra'] = key.extra
+        if key.condition:
+          requirement['environment'] = key.condition
+        metadata['run_requires'].append(requirement)
+
+    return metadata
 
 
 parser = argparse.ArgumentParser(
diff --git a/tools/piptool.par b/tools/piptool.par
index 11ec453cd7..56c267b7c3 100755
Binary files a/tools/piptool.par and b/tools/piptool.par differ
diff --git a/tools/whltool.par b/tools/whltool.par
index 7cb59c0fbe..83a61e7705 100755
Binary files a/tools/whltool.par and b/tools/whltool.par differ