add hyperlinks with gitfile:// URLs (#29)

Closes #29.

5 files changed, 67 insertions, 2 deletions

diff --git a/README.md b/README.md
index a093540..53fc85c 100644
--- a/README.md
+++ b/README.md
@@ -112,6 +112,25 @@ If you run with the `--serve` option then it will start a lightweight
 webserver and output a URL you can connect to for dynamically
 visualizing and navigating the dependency graph.
 
+### Setting up a `gitfile://` URL handler
+
+If you double-click any commit node on the dependency graph, your
+browser will be asked to launch a handler for a `gitfile://...` URL
+which points to that commit within the repository path on your local
+filesystem.  So if you configure your browser desktop environment,
+you can have a program such as [`gitk`](http://git-scm.com/docs/gitk)
+launch for viewing further details of that commit.  Obviously this
+only makes sense when viewing the graph via http://localhost.
+
+On most Linux machines, this can be set up via something like the
+following:
+
+    # First cd to the top of this git-deps repo.
+    repo="`pwd`"
+    ln -sf $repo/gitfile-handler ~/bin
+    ln -sf $repo/gitfile-handler.desktop ~/.local/share/applications
+    xdg-mime default gitfile-handler.desktop x-scheme-handler/gitfile
+
 Development / support / feedback
 --------------------------------
 
diff --git a/git-deps b/git-deps
index 410a475..0d3e2dd 100755
--- a/git-deps
+++ b/git-deps
@@ -726,7 +726,9 @@ def serve(options):
 
     @webserver.route('/options')
     def send_options():
-        return jsonify(options.__dict__)
+        client_options = options.__dict__
+        client_options['repo_path'] = os.getcwd()
+        return jsonify(client_options)
 
     @webserver.route('/deps.json/<commitish>')
     def deps(commitish):
diff --git a/gitfile-handler b/gitfile-handler
new file mode 100755
index 0000000..5fc5d3e
--- /dev/null
+++ b/gitfile-handler
@@ -0,0 +1,34 @@
+#!/usr/bin/python
+
+from __future__ import print_function
+
+import os
+import re
+import subprocess
+import sys
+from urlparse import urlparse, urljoin
+
+def abort(msg, exitcode=1):
+    print(msg, file=sys.stderr)
+    sys.exit(exitcode)
+
+def usage():
+    abort("usage: git-handler URL")
+
+def main():
+    if len(sys.argv) != 2:
+        usage()
+
+    url = urlparse(sys.argv[1])
+
+    if url.scheme != 'gitfile':
+        abort("URL must use gitfile:// scheme")
+
+    repo = os.path.join(url.netloc, url.path)
+    rev = url.fragment
+    os.chdir(repo)
+
+    subprocess.Popen(['gitk', '--all', '--select-commit=%s' % rev])
+
+if __name__ == "__main__":
+    main()
diff --git a/gitfile-handler.desktop b/gitfile-handler.desktop
new file mode 100644
index 0000000..dfef2d5
--- /dev/null
+++ b/gitfile-handler.desktop
@@ -0,0 +1,7 @@
+[Desktop Entry]
+Name=gitk launcher
+Exec=gitfile-handler %u
+# Icon=emacs-icon
+Type=Application
+Terminal=false
+MimeType=x-scheme-handler/gitfile;
diff --git a/html/js/git-deps-graph.coffee b/html/js/git-deps-graph.coffee
index 6157a42..1148109 100644
--- a/html/js/git-deps-graph.coffee
+++ b/html/js/git-deps-graph.coffee
@@ -284,7 +284,7 @@ draw_new_nodes = (fg, g_enter) ->
     rects = g_enter.append('rect')
         .attr('rx', 5)
         .attr('ry', 5)
-        .on('dblclick', (d) -> explore_node d)
+        .on('dblclick', (d) -> launch_viewer d)
 
     labels = g_enter.append('text').text((d) ->
         d.name
@@ -310,6 +310,9 @@ explore_node = (d) ->
     else
         add_commitish d.sha1
 
+launch_viewer = (d) ->
+    window.location.assign "gitfile://#{options.repo_path}##{d.sha1}"
+
 new_data_notification = (new_data) ->
     new_nodes = new_data[0]
     new_deps = new_data[1]