Action Statistics (from a JumpCloud "Assignment")

A library to assist in keeping and reporting statistics for some set of timed actions.

Specification

See here.

Installation

We assume that only Go applications will be using this library.

Use

$ go get github.com/cargregter/jc_assignment

Testing

Unit and integration tests are provided. A couple of mechanisms for running the tests are suggested.

go test

From directory .../jc_assignment/action, use

$ go test --test.v

GoConvey

GoConvey provides a nice framework within which to define test cases along with lots of matchers and a convenient web interface.

Usage

API

This library exposes two functions.

• Add(action string) error: Used to add the details of an action, the action parameter is a JSON string like

`{"action":"run", "time":75}`

Units of the time value are your choice. An error is returned if there is difficulty interpreting the input.

• GetStats() string: Used to obtain a report of the statistics having been added. The report is in formatted JSON form like

[
    {
        "action": "jump",
        "avg": 200
    },
    {
        "action": "run",
        "avg": 75
    }
]

Example Code

In your code, add lines like the following as appropriate:

...

import "github.com/cargregter/jc_assignment/action"

    ...
    errAdd := action.Add(`{"action":"jump", "time":100}`)
    if errAdd != nil {
    	return errAdd
    }
    
    ...
    statsReport := action.GetStats()
    if statsReport == "" {
    	return error.New("error generating statistics report")
    }
    
    ...

Notes

Parallelism

Both functions Add() and GetStats() are thread safe. However, keep in mind that if you invoke GetStats() while Add() is being invoked (or could be invoked) in parallel, the returned statistics report may or may not include the latest added actions.

Storage

Added actions are kept in memory. There are no provisions made to recover stored actions in the event that the application using this library should fail.

Improvements

Persistence

There may be value in writing actions to a persistent store or at least offering the option.

More Statistics

Of course, more statistics could be added as thought useful. It would likely mean capturing more raw data. But even with what we currently capture, one could see the usefulness of including the total number of observations for an action, and perhaps the mode and median of the provided times.

Editing Actions

Currently actions can only be added. There is no contemplation of modifying or removing them, except that each added action is kept separately.

Dumping Action Detail

While all action detail is kept, there is currently no mechanism for dumping them for inspection.