Metrics CLi

A command-line interface for an existing machine metrics JSON Web API specification.

JSON Web API

The prexisting JSON Web API responds to the following request:

GET /: which returns a JSON mapping of machine ids to URLs

CLi Description

Given a single argument (url), which will be the URL of the Web API to use. The metrics CLI makes a GET request to the given URL and receives a JSON mapping of machine ids to URLs.

For each machine, the metrics CLi obtains its metrics by making a GET request to the specified URL. The metrics CLi reports:

The number of machines which provide that metric.
Which machine has the lowest value.
Which machine has the highest value.
The standard deviation of the values.

The metrics CLi then prints the metrics summary in the following format:

METRIC: metric_1
NUM: 5
MINIMUM: machine_1
MAXIMUM: machine_2
STD: 5.76

METRIC: metric_2
NUM: 5
MINIMUM: machine_4
MAXIMUM: machine_2
STD: 7.18

Or if you specify the --pretty option the metrics summary is output in the following format:

+----------+-----+-----------+-----------+------+
| METRIC   | NUM | MINIMUM   | MAXIMUM   | STD  |
+----------+-----+-----------+-----------+------+
| metric_1 | 5   | machine_1 | machine_5 | 1.58 |
+----------+-----+-----------+-----------+------+
| metric_2 | 5   | machine_1 | machine_5 | 9.67 |
+----------+-----+-----------+-----------+------+

Installation

Add this line to your application's Gemfile:

gem 'metrics' :git => 'git@github.com:mattfreer/metrics_cli.git'

And then execute:

$ bundle install

Usage

$ bundle exec metrics [options] url

Options:

-h, --help: Show command line help
--pretty: Make the metrics pretty
--version: Show help/version info
--log-level LEVEL (debug|info|warn|error|fatal) (Default: info): Set the logging level

Arguments:

url: URL of the Web API to use

Development Tests

If you Clone or Fork this project you can run the intergration (cucumber) and unit tests (rspec) by running:

bundle exec rake

mattfreer / metrics_cli