Add ModifyRequestHeaderPlugin

proxy/plugin/__init__.py

@@ -32,6 +32,7 @@
 from .filter_by_client_ip import FilterByClientIpPlugin
 from .filter_by_url_regex import FilterByURLRegexPlugin
 from .modify_chunk_response import ModifyChunkResponsePlugin
+from .modify_request_header import ModifyRequestHeaderPlugin
 from .redirect_to_custom_server import RedirectToCustomServerPlugin
 
 
@@ -53,4 +54,5 @@
     'CustomDnsResolverPlugin',
     'CloudflareDnsResolverPlugin',
     'ProgramNamePlugin',
+    'ModifyRequestHeaderPlugin',
 ]

proxy/plugin/modify_request_header.py

@@ -0,0 +1,31 @@
+# -*- coding: utf-8 -*-
+"""
+    proxy.py
+    ~~~~~~~~
+    ⚡⚡⚡ Fast, Lightweight, Pluggable, TLS interception capable proxy server focused on
+    Network monitoring, controls & Application development, testing, debugging.
+
+    :copyright: (c) 2013-present by Abhinav Singh and contributors.
+    :license: BSD, see LICENSE for more details.
+"""
+from typing import Optional
+
+from ..http.proxy import HttpProxyBasePlugin
+from ..http.parser import HttpParser
+from ..common.utils import bytes_
+from ..common.version import __version__
+
+
+class ModifyRequestHeaderPlugin(HttpProxyBasePlugin):
+    """Modify request header before sending to upstream server."""
+
+    def handle_client_request(self, request: HttpParser) -> Optional[HttpParser]:
+        """NOTE: Modification of client request under TLS interception WILL NOT WORK
+        through before_upstream_connection hook override.  This example plugin is demonstrate
+        how to modify headers for all scenarios (with or without interception).
+        """
+        request.add_header(
+            b'x-proxy-py-version',
+            bytes_(__version__),
+        )
+        return request