[PATCH 1/3] extras/proxy_pass: implicit $fullpath expansion for upstreams

[Eric Wong <e@80x24.org>]

This is slightly more nginx-style behavior and allows simpler
configuration.
---
 extras/proxy_pass.rb | 24 +++++++++++++++---------
 1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/extras/proxy_pass.rb b/extras/proxy_pass.rb
index 15cbae5..d435ebe 100644
--- a/extras/proxy_pass.rb
+++ b/extras/proxy_pass.rb
@@ -112,25 +112,31 @@ class ProxyPass # :nodoc:
 
   def initialize(dest, timeout = 5)
     case dest
-    when %r{\Ahttp://([^/]+)(/.*)\z}
+    when %r{\Ahttp://([^/]+)(/.*)?\z}
       path = $2
       host, port = $1.split(':')
       @sockaddr = Socket.sockaddr_in(port || 80, host)
-
-      # methods from Rack::Request we want:
-      allow = %w(fullpath host_with_port host port url path)
-      @path = path
-      want = path.scan(/\$(\w+)/).flatten! || []
-      diff = want - allow
-      diff.empty? or
-               raise ArgumentError, "vars not allowed: #{diff.uniq.join(' ')}"
     else
       raise ArgumentError, "destination must be an HTTP URL"
     end
+    init_path_vars(path)
     @pool = ConnPool.new
     @timeout = timeout
   end
 
+  def init_path_vars(path)
+    path ||= '$(fullpath)'
+    # methods from Rack::Request we want:
+    allow = %w(fullpath host_with_port host port url path)
+    want = path.scan(/\$(\w+)/).flatten! || []
+    diff = want - allow
+    diff.empty? or
+             raise ArgumentError, "vars not allowed: #{diff.uniq.join(' ')}"
+
+    # kill leading slash just in case...
+    @path = path.gsub(%r{\A/(\$(?:fullpath|path))}, '\1')
+  end
+
   def call(env)
     request_method = env['REQUEST_METHOD']
     req = Rack::Request.new(env)
-- 
EW