Readme updated.

README.md

@@ -1,3 +1,5 @@
+# Simple producer/consumer web link extractor
+
 [![Build Status](https://travis-ci.org/garncarz/link-extractor.svg?branch=master)](https://travis-ci.org/garncarz/link-extractor)
 [![Coverage Status](https://coveralls.io/repos/github/garncarz/link-extractor/badge.svg?branch=master)](https://coveralls.io/github/garncarz/link-extractor?branch=master)
 
@@ -7,6 +9,7 @@
 Needed:
 - Python 3.5
 - Redis
+- Supervisord
 
 Preferably under `virtualenv`:
 
@@ -23,9 +26,36 @@ Customized settings are expected in `extractor/settings_local.py`.
 
 ## Usage
 
-`redis-server redis.conf`
-
-`celery -A extractor worker -l info`
+`supervisord` starts Supervisord with background services
+(Redis, Celery workers – "consumers").
+They can be controlled by `supervisorctl` then.
+Logs are stored in the `log` directory.
+
+`./app.py` is the "producer", expecting list of URLs on the standard input.
+They are parsed, so you can use HTML as input: `./app.py < index.html`.
+
+Each URL from input is processed by consumers in a way that
+the referenced webpage is downloaded and parsed for absolute URLs,
+which are then saved in a JSON file in the `out` directory.
+The output file name is an MD5 hash of the input URL.
+
+
+## Example
+
+```sh
+$ supervisord  # if not already done before
+$ ./app.py
+http://example.com
+Ctrl+D
+$ jq < out/a9b9f04336ce0181a08e774e01113b31.json
+{
+  "url": "http://example.com",
+  "links": [
+    "http://www.iana.org/domains/example"
+  ],
+  "version": "0.1.0"
+}
+```
 
 
 ## Testing