Microservice to tracks real-time events.

The application was built using Typescript + node.js using express.js to expose REST methods. For persists the data, the microservice uses their own MYSQL database and typeORM for manage the persistence layer.

1. I assume to group all events for each hour. This means that every event track will count for the rounded-down time that happens.
2. For sake of simplicity, I assume that the count events will be a positive number.

I deployed the the application in Heroku cloud, so you will be able to execute microservice through the following URL:

http://infinite-mountain-00334.herokuapp.com/api/events

The REST API provides the following endpoints (Table 1) to satisfy requirements:

Table 1: summary of the REST API endpoints

Response content-Type: application/json This endpoint could return:

• HTTP 200
• HTTP 403: in case not provide the required param.
• HTTP 500: in case of an application error, i. e. error during the database communication.

Response content-Type: application/json This endpoint could return:

• HTTP 200
• HTTP 403: in case not provide the required param.
• HTTP 500 in case of application error, i. e. error during the database communication.

Response content-Type: application/json This endpoint could return:

• HTTP 200
• HTTP 403: in case you not provide the required params start_date and end_date, or in case the end_date won't be greather than the start_date.
• HTTP 500: in case of application error, i. e. error during the database communication.

Response content-Type: application/json This endpoint could return:

• HTTP 200
• HTTP 500: in case of application error, i. e. error during the database communication.

Response content-Type: image/png This endpoint could return:

• HTTP 200
• HTTP 500: in case of application error, i. e. error during the database communication.

All of the above mentioned returns the following response format:

• In case a succesfull response, the data field will have the required data, and the error will be null:

{
    "data": [ "..." ],
    "error": null
}

• In case a error response, the data field will be null, and the error will have a description of what hapenned:

{
    "data": null,
    "error": "..."
}

This excludes the histogram endpoint, which only returns this response format in case of error. Otherwise will return the png file