Welcome to PowerDale

PowerDale is a small town with around 100 residents. Most houses have a smartmeter installed that can save and send information about how much energy a house has used.

There are three major providers of energy in town that charge different amounts for the power they supply.

• Dr Evil's Dark Energy
• The Green Eco
• Power for Everyone

Introducing JOI Energy

JOI Energy is a new startup in the energy industry. Rather than selling energy they want to differentiate themselves from the market by recording their customers' energy usage from their smart meters and recommending the best suppler to meet their needs.

You have been placed into their development team, whose current goal is to produce an API which their customers and smart meters will interact with.

Unfortunately, two of the team are on annual leave, and another has called in sick! You are left with a ThoughtWorker to progress with the current user stories on the story wall. This is your chance to make an impact on the business, improve the code base and deliver value.

Story Wall

At JOI energy the development team use a story wall or kanban board to keep track of features or "stories" as they are worked on.

The wall you will be working from today has 7 columns:

• Backlog
• Ready for Dev
• In Dev
• Ready for Testing
• In Testing
• Ready for sign off
• Done

Examples can be found here https://leankit.com/learn/kanban/kanban-board/

Users

To trial the new JOI software 5 people from the JOI accounts team have agreed to test the service and share their energy data.

• Sarah - Smart Meter Id: "smart-meter-0", current power supplier: Dr Evil's Dark Energy.
• Peter - Smart Meter Id: "smart-meter-1", current power supplier: The Green Eco.
• Charlie - Smart Meter Id: "smart-meter-2", current power supplier: Dr Evil's Dark Energy.
• Andrea - Smart Meter Id: "smart-meter-3", current power supplier: Power for Everyone.
• Alex - Smart Meter Id: "smart-meter-4", current power supplier: The Green Eco.

Overview

JOI Energy is a new energy company that uses data to ensure customers are able to be on the best price plan for their energy consumption.

API

Below is a list of API endpoints with their respective input and output.

Store Readings

Endpoint

POST
/readings/store

Input

{
    "smartMeterId": <smartMeterId>,
    "electricityReadings": [
        { "time": <UTC-Time>, "reading": <reading> },
        ...
    ]
}

time: UTC time, e.g. 2024-04-13T19:41:26Z reading: kW reading of smart meter at that time, e.g. 0.0503

Get Stored Readings

Endpoint

GET
/readings/read/<smartMeterId>

smartMeterId: A string value, e.g. smart-meter-0

Output

[
    { "time": "2017-09-07T10:37:52.362Z", "reading": 1.3524882598124337 },
    ...
]

View Current Price Plan and Compare Usage Cost Against all Price Plans

Endpoint

GET
/price-plans/compare-all/<smartMeterId>

smartMeterId: A string value, e.g. smart-meter-0

Output

{
   "pricePlanId": "price-plan-2",
   "pricePlanComparisons": { 
       "price-plan-0": 21.78133785680731809,
       ...
   }
}

View Recommended Price Plans for Usage

Endpoint

GET
/price-plans/recommend/<smartMeterId>[?limit=<limit>]

smartMeterId: A string value, e.g. smart-meter-0

limit: Optional limit to display only a number of price plans, e.g. 2

Output

[
    { 
        "price-plan-0": 15.084324881035297
    },
    ...
]

Useful make commands

make run
make test
make lint
make build
make clean
make all
make             # default is make all

This has been created using go modules; to run the tests, just execute:

go test -race -cover -coverprofile=coverage.txt -covermode=atomic ./...

or (using make):

make test

The Makefile also supports other commands, such as:

make lint