serve hg more statically (#579)

* serve hg more statically

* include a helpful readme

Author: ewdurbin

salt/hg/config/hg.apache.conf.jinja

@@ -24,6 +24,14 @@
         Require all granted
     </Directory>
 
+    Alias /icons/ "/usr/share/apache2/icons/"
+
+    <Directory "/usr/share/apache2/icons">
+        Options FollowSymlinks
+        AllowOverride None
+        Require all granted
+    </Directory>
+
     # The lookup app is better run with few processes, since it uses a cache.
     WSGIDaemonProcess hglookup user=hg group=hg \
         threads=2 processes=1 maximum-requests=1000 \
@@ -36,38 +44,38 @@
 
     WSGIScriptAlias /lookup /srv/hg/wsgi/lookup.wsgi
 
-    # We need enough threads/processes for many long-running clones to run in
-    # parallel (e.g. for buildbots)
-    # NOTE: maximum-requests suspected to corrupt responses, see
-    # http://mercurial.selenic.com/bts/issue2595
-    WSGIDaemonProcess hgweb user=hg group=hg \
-        threads=2 processes=6 maximum-requests=1024 inactivity-timeout=300 \
-        display-name=hgweb
-    WSGIProcessGroup hgweb
+    # A lightweight standin for revision app to maintain support for /lookup
+    WSGIDaemonProcess hgrev user=hg group=hg \
+        threads=2 processes=4 maximum-requests=1000 \
+        display-name=hgrev
+    # The Location hack ensures the lookup app is run within
+    # this process group
+    <LocationMatch "^(.*)/rev/([A-Fa-f0-9]{12,40})/?">
+        WSGIProcessGroup hgrev
+    </LocationMatch>
+
+    WSGIScriptAliasMatch "^(.*)/rev/([A-Fa-f0-9]{12,40})/?" /srv/hg/wsgi/rev.wsgi
 
-    WSGIScriptAlias / /srv/hg/wsgi/python.wsgi
+    # Staticly serve hg repos over HTTP
+    DocumentRoot /srv/hg/hg-static/
+    <Directory /srv/hg/hg-static>
+        Options Indexes FollowSymlinks
+        IndexOptions FancyIndexing SuppressColumnSorting
+        HeaderName README.html
+        Require all granted
+    </Directory>
 
     ErrorDocument 410 /410.html
     RedirectMatch gone "/cpython/annotate/.*/NEWS$"
     RedirectMatch gone "/cpython-fullhistory/annotate/.*/NEWS$"
 
-    <Directory /srv/hg/wsgi>
-      Require all granted
-    </Directory>
-
     # Static files: logo, CSS, favicon... (wired to .../static/)
     # This is optional but a bit faster than letting Mercurial serve the files
     # NOTE: needs to be changed if hg gets wired to another dir or python
     # version
 
-    AliasMatch /static/([^/]*) /usr/share/mercurial/templates/static/$1
-    <Directory /usr/share/mercurial/templates/static/>
-      Require all granted
-    </Directory>
-
     <Location /_server-status>
         SetHandler server-status
-
         Require ip 127.0.0.1
     </Location>
 </VirtualHost>

salt/hg/files/hg/src/hgrev.py

@@ -0,0 +1,60 @@
+# hgrev.py
+#
+# Dump a revision of a given hg repo as a patch
+#
+# Written by Ee Durbin, 2025.
+
+import os
+import shlex
+import subprocess
+from wsgiref.simple_server import make_server
+
+
+class hgrev(object):
+    def __init__(self, verbose=False):
+        self.verbose = verbose
+
+    def successful_response(self, response, contents):
+        headers = [("Content-Type", "text/plain")]
+        response("200 OK", headers)
+        return [contents.encode()]
+
+    def failed_response(self, response, detail=""):
+        headers = [("Content-Type", "text/plain")]
+        response("404 Not Found", headers)
+        return [
+            detail.encode(),
+            "\nUsage: path/to/hg/repo/rev/HGHEXNODE (12 or 40 hex characters)\n".encode(),
+        ]
+
+    def __call__(self, env, response):
+        node = env.get("SCRIPT_NAME", "").strip("/")
+        repository = os.path.dirname(node).rstrip("/rev")
+        rev = os.path.basename(node)
+
+        hg_repo = os.path.join("/srv/hg/repos", repository, ".hg")
+        if not os.path.exists(hg_repo):
+            return self.failed_response(
+                response,
+                detail=f"repo not found ({repository}) ({rev})",
+            )
+
+        command = ["hg", "log", "-v", "-p", "-r", shlex.quote(rev)]
+
+        try:
+            result = subprocess.run(
+                command, cwd=hg_repo, capture_output=True, text=True, shell=False
+            )
+        except Exception as e:
+            return self.failed_response(response, detail=str(e))
+
+        return self.successful_response(response, result.stdout)
+
+
+if __name__ == "__main__":
+    application = hgrev(verbose=True)
+
+    httpd = make_server("", 8124, application)
+    sa = httpd.socket.getsockname()
+    print("Serving HTTP on", sa[0], "port", sa[1], "...")
+    httpd.serve_forever()

salt/hg/files/hg/wsgi/rev.wsgi

@@ -0,0 +1,10 @@
+import os
+import sys
+
+home = os.path.expanduser('~hg')
+
+sys.path.insert(0, os.path.join(home, 'src'))
+
+from hgrev import hgrev
+
+application = hgrev()