Strip request header values

extras/get-homebrew-formula-vars.py

@@ -0,0 +1,55 @@
+#!/usr/bin/env python
+"""
+Generate URLs and file hashes to be included in the Homebrew formula
+after a new release of HTTPie is published on PyPi.
+
+https://github.com/Homebrew/homebrew-core/blob/master/Formula/httpie.rb
+
+"""
+import hashlib
+import requests
+
+
+PACKAGES = [
+    'httpie',
+    'requests',
+    'pygments',
+]
+
+
+def get_info(package_name):
+    api_url = 'https://pypi.python.org/pypi/{}/json'.format(package_name)
+    resp = requests.get(api_url).json()
+    hasher = hashlib.sha256()
+    for release in resp['urls']:
+        download_url = release['url']
+        if download_url.endswith('.tar.gz'):
+            hasher.update(requests.get(download_url).content)
+            return {
+                'name': package_name,
+                'url': download_url,
+                'sha256': hasher.hexdigest(),
+            }
+    else:
+        raise RuntimeError(
+            '{}: download not found: {}'.format(package_name, resp))
+
+
+packages = {
+    package_name: get_info(package_name) for package_name in PACKAGES
+}
+
+
+httpie_info = packages.pop('httpie')
+print("""
+    url "{url}"
+    sha256 "{sha256}"
+""".format(**httpie_info))
+
+
+for package_info in packages.values():
+    print("""
+    resource "{name}" do
+        url "{url}"
+        sha256 "{sha256}"
+    end""".format(**package_info))

httpie/client.py

@@ -85,13 +85,23 @@ def dump_request(kwargs):
                      % repr_dict_nice(kwargs))
 
 
-def encode_headers(headers):
-    # This allows for unicode headers which is non-standard but practical.
-    # See: https://github.com/jkbrzt/httpie/issues/212
-    return dict(
-        (name, value.encode('utf8') if isinstance(value, str) else value)
-        for name, value in headers.items()
-    )
+def finalize_headers(headers):
+    final_headers = {}
+    for name, value in headers.items():
+        if value is not None:
+
+            # >leading or trailing LWS MAY be removed without
+            # >changing the semantics of the field value"
+            # -https://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html
+            # Also, requests raises `InvalidHeader` for leading spaces.
+            value = value.strip()
+
+            if isinstance(value, str):
+                # See: https://github.com/jkbrzt/httpie/issues/212
+                value = value.encode('utf8')
+
+        final_headers[name] = value
+    return final_headers
 
 
 def get_default_headers(args):
@@ -133,7 +143,7 @@ def get_requests_kwargs(args, base_headers=None):
     if base_headers:
         headers.update(base_headers)
     headers.update(args.headers)
-    headers = encode_headers(headers)
+    headers = finalize_headers(headers)
 
     credentials = None
     if args.auth: