propose nsed - file configuration tool

nsed/README.md

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+Nsed (No to Sed)
+================
+
+**Say No To Sed**
+
+## Motivation
+
+A while back i was given a task to deploy a bunch of software components onto an amazon EC2 instance:
+
+- Graphite + Grafana
+- Elasticsearch + Logstash + Kibana (ELK)
+- Nagios
+- ...
+- ...
+
+Immediately i thought to myself: "Hey, no sweat, im sure DockerHub has containers for all these guys!".
+
+This means all i will have to do is write a *docker-compose* file that defines all of them. A quick lookup at the
+DockerHub registery revieled that even though containers existed for most of these components, they were not exactly
+what i needed. They were either hardcoding some configuration (for example elasticsearch port), or bringing in
+extra components that i just did not need (for example StatsD with the graphite container).
+
+This meant that i had to start writing my own docker files, and configure each component to my needs. And let me tell
+you, there was a lot of configuration to do:
+
+- Retention policies for graphite storage (carbon.conf)
+- Elasticsearch port (elasticsearch.yml)
+- Grafana datasources and security (config.js)
+- Logstash filters (logstash.conf)
+- Nagios checks (nagios.cfg)
+- ...
+- ...
+
+Effectively, this meant that i had to manipulate a lot of different configuration files from within the Dockerfile.
+So i did what every programmer would do:
+
+1.  Bang my head against the table for a while.
+2.  Freshen up my 'sed' skills.
+
+After a couple of hours, and with very little hair left, i thought to myself: "Man, wouldn't it be great if every one
+of these software components would provide a command line tool for configurating the damn thing?!"
+
+Imagine that in order to configure the elasticsearch port, all you had to do was:
+
+`$ elasticsearch config port=9201`
+
+You may say, im a dreamer...but im not the only one...In fact, you have probably already seen something like this
+in action: `$ git config user.email [email protected]`. Yeap, linus has done it again...
+
+I then thought that there was nothing special about elasticsearch configuration. It is just a YAML file that can
+be very easily manipulated using some basic python code (YAML can be deserialized into a dict), So why not write
+a small python script that does exactly that? i could then use that script to configure any YAML file very easily:
+
+`$ python yaml_patcher.py /etc/elasticsearch.yml port 9201`
+
+The script also supprted nested configuration:
+
+`$ python yaml_patcher.py /etc/elasticsearch.yml security.admin_password pass`
+
+And even structured data:
+
+`$ python yaml_patcher.py /etc/elasticsearch.yml security {"admin_password": "pass", "admin_user": "admin"} pass`
+
+This proved to be extremely useful for me, especially because more and more tools are now switching to
+YAML configuration. But i didn't want to stop there, i could do the same thing for many standrad file types:
+
+- json
+- init
+- properties
+- ...
+- ...
+
+And this is how *fileconfig* came to be, hope you enjoy it!