git-instaweb: add Python builtin http.server support
With this patch it is possible to launch git-instaweb by using Python http.server CGI handler via `-d python` option. git-instaweb generates a small wrapper around the http.server (in GIT_DIR/gitweb/) that address a limitation of the CGI handler where CGI scripts have to be in a cgi-bin subdirectory and directory index can't be easily changed. To keep the implementation small, gitweb is running on url `/cgi-bin/gitweb.cgi` and an automatic redirection is done when opening `/`. The generated wrapper is compatible with both Python 2 and 3. Python is by default installed on most modern Linux distributions which enables running `git instaweb -d python` without needing anything else. Signed-off-by: Arti Zirk <arti.zirk@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Arti Zirk committed
Jan 28, 2019 at 15:24 UTC
2eb14bb2d41b27d23120206bbe3d409a83cf042f
2 files changed
+128
-2
Documentation/git-instaweb.txt
+2
-1
@@ -29,7 +29,8 @@ OPTIONS
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The HTTP daemon command-line that will be executed.
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Command-line options may be specified here, and the
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configuration file will be added at the end of the command-line.
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- Currently apache2, lighttpd, mongoose, plackup and webrick are supported.
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+ Currently apache2, lighttpd, mongoose, plackup, python and
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+ webrick are supported.
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(Default: lighttpd)
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-m::
git-instaweb.sh
+126
-1
@@ -67,6 +67,13 @@ resolve_full_httpd () {
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httpd_only="${httpd%% *}" # cut on first space
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return
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;;
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+ *python*)
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+ # server is started by running via generated gitweb.py in
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+ # $fqgitdir/gitweb
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+ full_httpd="$fqgitdir/gitweb/gitweb.py"
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+ httpd_only="${httpd%% *}" # cut on first space
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+ return
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+ ;;
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esac
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httpd_only="$(echo $httpd | cut -f1 -d' ')"
@@ -110,7 +117,7 @@ start_httpd () {
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# don't quote $full_httpd, there can be arguments to it (-f)
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case "$httpd" in
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- *mongoose*|*plackup*)
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+ *mongoose*|*plackup*|*python*)
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#These servers don't have a daemon mode so we'll have to fork it
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$full_httpd "$conf" &
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#Save the pid before doing anything else (we'll print it later)
@@ -595,6 +602,121 @@ EOF
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rm -f "$conf"
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}
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+python_conf() {
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+ # Python's builtin http.server and its CGI support is very limited.
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+ # CGI handler is capable of running CGI script only from inside a directory.
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+ # Trying to set cgi_directories=["/"] will add double slash to SCRIPT_NAME
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+ # and that in turn breaks gitweb's relative link generation.
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+
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+ # create a simple web root where $fqgitdir/gitweb/$httpd_only is our root
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+ mkdir -p "$fqgitdir/gitweb/$httpd_only/cgi-bin"
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+ # Python http.server follows the symlinks
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+ ln -sf "$root/gitweb.cgi" "$fqgitdir/gitweb/$httpd_only/cgi-bin/gitweb.cgi"
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+ ln -sf "$root/static" "$fqgitdir/gitweb/$httpd_only/"
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+
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+ # generate a standalone 'python http.server' script in $fqgitdir/gitweb
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+ # This asumes that python is in user's $PATH
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+ # This script is Python 2 and 3 compatible
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+ cat > "$fqgitdir/gitweb/gitweb.py" <<EOF
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+#!/usr/bin/env python
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+import os
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+import sys
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+
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+# Open log file in line buffering mode
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+accesslogfile = open("$fqgitdir/gitweb/access.log", 'a', buffering=1)
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+errorlogfile = open("$fqgitdir/gitweb/error.log", 'a', buffering=1)
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+
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+# and replace our stdout and stderr with log files
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+# also do a lowlevel duplicate of the logfile file descriptors so that
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+# our CGI child process writes any stderr warning also to the log file
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+_orig_stdout_fd = sys.stdout.fileno()
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+sys.stdout.close()
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+os.dup2(accesslogfile.fileno(), _orig_stdout_fd)
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+sys.stdout = accesslogfile
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+
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+_orig_stderr_fd = sys.stderr.fileno()
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+sys.stderr.close()
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+os.dup2(errorlogfile.fileno(), _orig_stderr_fd)
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+sys.stderr = errorlogfile
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+
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+from functools import partial
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+
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+if sys.version_info < (3, 0): # Python 2
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+ from CGIHTTPServer import CGIHTTPRequestHandler
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+ from BaseHTTPServer import HTTPServer as ServerClass
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+else: # Python 3
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+ from http.server import CGIHTTPRequestHandler
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+ from http.server import HTTPServer as ServerClass
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+
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+
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+# Those environment variables will be passed to the cgi script
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+os.environ.update({
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+ "GIT_EXEC_PATH": "$GIT_EXEC_PATH",
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+ "GIT_DIR": "$GIT_DIR",
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+ "GITWEB_CONFIG": "$GITWEB_CONFIG"
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+})
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+
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+
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+class GitWebRequestHandler(CGIHTTPRequestHandler):
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+
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+ def log_message(self, format, *args):
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+ # Write access logs to stdout
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+ sys.stdout.write("%s - - [%s] %s\n" %
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+ (self.address_string(),
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+ self.log_date_time_string(),
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+ format%args))
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+
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+ def do_HEAD(self):
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+ self.redirect_path()
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+ CGIHTTPRequestHandler.do_HEAD(self)
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+
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+ def do_GET(self):
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+ if self.path == "/":
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+ self.send_response(303, "See Other")
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+ self.send_header("Location", "/cgi-bin/gitweb.cgi")
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+ self.end_headers()
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+ return
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+ self.redirect_path()
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+ CGIHTTPRequestHandler.do_GET(self)
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+
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+ def do_POST(self):
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+ self.redirect_path()
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+ CGIHTTPRequestHandler.do_POST(self)
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+
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+ # rewrite path of every request that is not gitweb.cgi to out of cgi-bin
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+ def redirect_path(self):
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+ if not self.path.startswith("/cgi-bin/gitweb.cgi"):
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+ self.path = self.path.replace("/cgi-bin/", "/")
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+
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+ # gitweb.cgi is the only thing that is ever going to be run here.
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+ # Ignore everything else
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+ def is_cgi(self):
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+ result = False
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+ if self.path.startswith('/cgi-bin/gitweb.cgi'):
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+ result = CGIHTTPRequestHandler.is_cgi(self)
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+ return result
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+
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+
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+bind = "127.0.0.1"
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+if "$local" == "true":
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+ bind = "0.0.0.0"
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+
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+# Set our http root directory
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+# This is a work around for a missing directory argument in older Python versions
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+# as this was added to SimpleHTTPRequestHandler in Python 3.7
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+os.chdir("$fqgitdir/gitweb/$httpd_only/")
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+
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+GitWebRequestHandler.protocol_version = "HTTP/1.0"
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+httpd = ServerClass((bind, $port), GitWebRequestHandler)
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+
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+sa = httpd.socket.getsockname()
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+print("Serving HTTP on", sa[0], "port", sa[1], "...")
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+httpd.serve_forever()
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+EOF
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+
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+ chmod a+x "$fqgitdir/gitweb/gitweb.py"
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+}
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+
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gitweb_conf() {
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cat > "$fqgitdir/gitweb/gitweb_config.perl" <<EOF
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#!@@PERL@@
@@ -623,6 +745,9 @@ configure_httpd() {
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*plackup*)
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plackup_conf
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;;
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+ *python*)
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+ python_conf
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+ ;;
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*)
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echo "Unknown httpd specified: $httpd"
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exit 1