update docs

README.md

@@ -1,29 +1,62 @@
 <img src="https://raw.githubusercontent.com/redfi/redfi/master/static/[email protected]" width="400px">
 
-RedFI acts as a proxy between the client and redis with the capability
-of injecting faults on the fly, based off the rules given by you.
-
-```bash
-./redfi -redis 127.0.0.1:6379 -addr 127.0.0.1:8083 -plan plan.json
-```
+RedFI acts as a proxy between the client and Redis with the capability
+of injecting faults on the fly, based on the rules given by you.
 
+## Features
+- Simple to use. It's just a binary that you execute.
+- Transparent for the client.
+- Flexibility to inject failures on Redis Commands you define.
+- Limit failure injection to a percentage of the commands.
+- Limit failure injection to certain clients only.
+- Inject latency, drop connections, return empty responses.
 
 ## Why?
-To gain trust in systems that utilize redis as a backing store.
+We believe that to gain trust in your system,
+you must test it against various scenarios of failures, before deploying it to production.
+These tests should also be part of your CI, to catch code changes that might introduce regressions.
+This would help you understand the limits of your system, and how resilient it is against Redis' failures.
+
+## How it Works
+RedFI is a proxy that sets between the client and the actual Redis server.
+On every incoming command from the client,
+it checks the list of failure rules provided by you, and then it applies the first rule that matches the request.
+
+```bash
+Usage of ./redfi
+  -addr string
+    	address for the proxy to listen on (default "127.0.0.1:8083")
+  -redis string
+    	address to the redis server, to proxy requests to (default "127.0.0.1:6379")
+  -plan string
+    	path to the plan.json
+```
 
 
 ### plan.json example
-```json
+```javascript
 {
+    // the failure proxy will pick the first rule that applies to the client request
+    // so try to have the specific rules at the top, and the general ones at the bottom
     "rules": [
+        // will always delay GET commands by 1000 milliseconds
         {
-            "command": "get",
+            "command": "GET",
             "delay": 1000
         },
+        // drop connections of client 159.0.147.225:9003 only 50% of the time
         {
+            "clientAddr": "159.0.147.225:9003",
             "percentage": 50,
-            "clientAddr": "127.0.0.1",
             "drop": true
+        },
+        // this rule would be selected for all commands that aren't by 159.0.147.225:9003
+        // and aren't GET commands.
+        // But it will return nil to the client instead of the real response
+        // only 50% of the time
+        {
+            "percentage": 50,
+            "returnEmpty": true
         }
     ]
 }