adding help

README.md

@@ -3,11 +3,61 @@ A Rack middleware that should indicate the health of your service.
 
 
 ## Usage
+Here is a simple example (see `examples`)
+
+    map '/ping' do
+      use Rack::Ping do |ping|
+        ping.check_url  "http://localhost:9292/"
+        ping.ok_regex /goodbye/
+      end
+    end
+
+    run lambda{|env| [200, {'Content-Type' => 'text/html'}, ["hello"]]}
+
+## Options
+
+When building/mounting your rack, use the `ping` configuration variable,
+specify:
+
+* `version` is an accessor for your application version. `App::VERSION`
+  would be a good idea.
+* `check_url` is a url that `ping` will fetch and run `ok_regex` on. If
+  the match is ok, we're good. You must specify `check_url` and
+`ok_regex` togather. `timeout_secs` is the amount of seconds we wait
+until spitting out an error.
+* `check` will accept a block to run. This is a good alternative to
+  `check_url`: run a couple of sanity checks to indicate you're good.
+* `ok_code`, `error_code`, `ok_text`, `error_text` are configuration for
+  you to use, to configure against LB quirks. The default config should
+work against ELBs (Amazon elastic LB).
+
+  :version => '0',
+        :check_url => nil,
+        :ok_regex => nil,
+        :ok_text => 'ok',
+        :ok_code => 200,
+        :timeout_secs => 5,
+        :error_text => 'error',
+        :error_code => 500
+
+## Headers
+
+`ping` will output intelligent headers. First `x-ping-error` will try to
+explain why ping failed.  
+
+Next, `x-app-version` will expose the current deployed version of your
+app. This is good in order to validate nothing crawled up to production,
+as well as validation for post-production deployment.  
+
+`ping` will bust any browser/client cache for you.
+
+
+## Contributing
+
+Fork, implement, add tests, pull request, get my everlasting thanks and a respectable place here :).
+
+
+## Copyright
+
+Copyright (c) 2011 [Dotan Nahum](http://gplus.to/dotan) [@jondot](http://twitter.com/jondot). See MIT-LICENSE for further details.
 
-use Rack::Ping do |ping|
-  ping.version = "4.0"
-  ping.check_url = "http://localhost:234/api"
-  ping.ok_regex = /Welcome to Acme API/
-  ping.ok_text = 'ok'
-  ping.ok_code = 200
-end