Opening Hours

The code in this repository contains a simple REST API that receives JSON data as input and returns a human readable output as response. The data received is structured JSON of opening hours for a restaurant and this information gets coerced into a text understood by humans.

Preamble

We will write an endpoint that accepts JSON-formatted opening hours of a restaurant as an input and returns the rendered human readable format as a text output.

Input JSON consists of keys indicating days of a week and corresponding opening hours as values. One JSON file includes data for one restaurant.

{
    <dayofweek>: <opening hours>
    <dayofweek>: <opening hours>
    ...
}

<dayofweek>: monday / tuesday / wednesday / thursday / friday / saturday / sunday
<opening hours>: an array of objects containing opening hours. Each object consist of two keys:

• type: open or close
• value: opening / closing time as UNIX time (1.1.1970 as a date),
  e.g. 32400 = 9 AM, 37800 = 10.30 AM,
  max value is 86399 = 11.59:59 PM

Example: on Mondays a restaurant is open from 9 AM to 8 PM

{
    "monday" : [
        {
            "type" : "open",
            "value" : 32400
        },
        {
            "type" : "close",
            "value" : 72000
        }
    ],
    ...
}

Special cases

• If a restaurant is closed the whole day, an array of opening hours is empty.
  • “tuesday”: [] means a restaurant is closed on Tuesdays
• A restaurant can be opened and closed multiple times during the same day,
  • E.g. on Mondays from 9 AM - 11 AM and from 1 PM to 5 PM
• A restaurant might not be closed during the same day
  • A restaurant can be opened e.g. on a Friday evening and closed early Saturday morning. In that case friday-object includes only the opening time. Closing time is part of the saturday-object.
  • When printing opening hours which span between multiple days, closing time is always a part of the day when a restaurant was opened (e.g. Friday 8 PM - 1 AM)

{
    "friday" : [
        {
            "type" : "open",
            "value" : 64800
        }
    ],
    “saturday”: [
        {
            "type" : "close",
            "value" : 3600
        },
        {
            "type" : "open",
            "value" : 32400
        },
        {                        # A restaurant is open:
            "type" : "close",    # Friday: 6 PM - 1 AM
            "value" : 39600      # Saturday: 9 AM -11 AM, 4 PM - 11 PM
        },
        {
            "type" : "open",
            "value" : 57600
        },
        {
            "type" : "close",
            "value" : 82800
        }
    ]
}

Running and testing the solution

In order to run this basic example you would need to have the following installed

• Java Development Kit 11 and setup JAVA_HOME (Download for your platform)
• cURL
• Gradle (Optional)

Steps to follow

The steps listed below assume you are running from a linux shell (Bash), adapt the instructions for your platform.

1. Clone this repository opening-hours

2. Navigate to the opening-hours directory

   > cd ./opening-hours

   At the root of this directory, you should find a file build.gradle.kts.

3. Execute the gradle task to start a Netty server

   > ./gradlew bootRun

4. From a different shell make an HTTP request

   > curl --location --request POST 'http://localhost:8080/opening-hours' \
   --header 'Content-Type: application/json' \
   --data-raw '{
       "tuesday": [
           {
               "type": "open",
               "value": 36000
           },
           {
               "type": "close",
               "value": 64800
           }
       ],
       "wednesday": [],
       "monday": [],
       "thursday": [
           {
               "type": "open",
               "value": 37800
           },
           {
               "type": "close",
               "value": 64800
           }
       ],
       "friday": [
           {
               "type": "open",
               "value": 36000
           }
       ],
       "saturday": [
           {
               "type": "close",
               "value": 3600
           },
           {
               "type": "open",
               "value": 36000
           }
       ],
       "sunday": [
           {
               "type": "close",
               "value": 3600
           },
           {
               "type": "open",
               "value": 43200
           },
           {
               "type": "close",
               "value": 75600
           }
       ]
   }'

   You should get the following output

   > Monday: Closed
     Tuesday: 10 AM - 6 PM
     Wednesday: Closed
     Thursday: 10:30 AM - 6 PM
     Friday: 10 AM - 1 AM
     Saturday: 10 AM - 1 AM
     Sunday: 12 PM - 9 PM

Next steps: Try adjusting your payload and view the output for different inputs