COVID19WebServer

This project is a home assignment about creating a simple web server utilizing Covid-19 API.

Requirements / Installation

This project is written in Node.js and was tested on v14.18.1.
To install it on linux machine run the following:

sudo apt install nodejs

Other dependencies:

• map-expire:

  npm install map-expire
  

How to run the server

Simply run the main file, like so:

node main.js <hostname> <port>

Whereas <hostname> is a string of the hostname and <port> is an integer of the listing port.
For example:

node main.js localhost 8080

How to interact with the server (protocol)

As a web server we work with http protocol.

Protocol base:
http://<hostname>:<port>

Daily new confirmed cases in a given country

Click to Expand

• Method: GET.
• Base: /?protocol=daily.
• Required query parameters:
  • country: string of any country name.
  • date: string of the date format DD-MM-YYYY.
• Return: non-negative int.
• Example:
  • Input:

    curl "http://localhost:8080/?protocol=daily&country=France&date=25-10-2021"
    

  • Output:

    1283
    

Register a user

Click to Expand

• Method: POST.
• Base: /.
• Body: JSON.
• Required query parameters:
  • protocol: The following string: addUser.
  • username: string of a username (no spaces, case insensitive).
• Return: none.
• Example:
  • Input:

    curl --header "Content-Type: application/json" \
         --request POST \
         --data '{"protocol": "addUser", "username":"Shimi"}' \
         "http://localhost:8080/"
    

Add a country to user's list

Click to Expand

• Method: POST.
• Base: /.
• Body: JSON.
• Required query parameters:
  • protocol: The following string: addCountry.
  • username: string of a username (no spaces, case insensitive).
  • country: string of any country name.
• Return: none.
• Example:
  • Input:

    curl --header "Content-Type: application/json" \
         --request POST \
         --data '{"protocol": "addCountry", "username":"Shimi", "country":"France"}' \
         "http://localhost:8080/"
    

Remove a country to user's list

Click to Expand

• Method: POST.
• Base: /.
• Body: JSON.
• Required query parameters:
  • protocol: The following string: removeCountry.
  • username: string of a username (no spaces, case insensitive).
  • country: string of any country name.
• Return: none.
• Example:
  • Input:

    curl --header "Content-Type: application/json" \
         --request POST \
         --data '{"protocol": "removeCountry", "username":"Shimi", "country":"France"}' \
         "http://localhost:8080/"
    

Get user's country list

Click to Expand

• Method: GET.
• Base: /?protocol=countryList.
• Required query parameters:
  • username: string of a username (no spaces, case insensitive).
• Return: JSON with array of countries.
• Example:
  • Input:

    curl "http://localhost:8080/?protocol=countryList&username=Shimi"
    

  • Output:

    [
      "France",
      "Germany"
    ]

Get the number of deaths cases for each country in the user's list at a given date range

Click to Expand

• Method: GET.
• Base: /?protocol=numOfDeath.
• Required query parameters:
  • username: string of a username (no spaces, case insensitive).
  • from: string of the date format DD-MM-YYYY.
  • to: string of the date format DD-MM-YYYY.
• Return: JSON with which maps each country to his dates (each date maps to the number of deaths cases).
• Example:
  • Input:

    curl "http://localhost:8080/?protocol=numOfDeath&username=Shimi&from=25-10-2021&to=28-10-2021"
    

  • Output:

    {
      "France": {
        "25-10-2021": 43,
        "26-10-2021": 28,
        "27-10-2021": 33,
        "28-10-2021": 28
      },
      "Germany": {
        "25-10-2021": 27,
        "26-10-2021": 217,
        "27-10-2021": 124,
        "28-10-2021": 33
      }
    }

Get the number of confirmed cases for each country in the user's list at a given date range

Click to Expand

• Method: GET.
• Base: /?protocol=numOfConfirmed.
• Required query parameters:
  • username: string of a username (no spaces, case insensitive).
  • from: string of the date format DD-MM-YYYY.
  • to: string of the date format DD-MM-YYYY.
• Return: JSON with which maps each country to his dates (each date maps to the number of confirmed cases).
• Example:
  • Input:

    curl "http://localhost:8080/?protocol=numOfConfirmed&username=Shimi&from=25-10-2021&to=28-10-2021"
    

  • Output:

    {
      "France": {
        "25-10-2021": 1283,
        "26-10-2021": 6040,
        "27-10-2021": 6528,
        "28-10-2021": 5899
      },
      "Germany": {
        "25-10-2021": 9359,
        "26-10-2021": 31402,
        "27-10-2021": 28826,
        "28-10-2021": 8079
      }
    }

Get the country (from the user's list) with the highest deaths cases relative to the country population

Click to Expand

• Method: GET.
• Base: /?protocol=highestDeaths.
• Required query parameters:
  • username: string of a username (no spaces, case insensitive).
  • from: string of the date format DD-MM-YYYY.
  • to: string of the date format DD-MM-YYYY.
• Return: JSON with which maps each date to his country.
• Example:
  • Input:

    curl "http://localhost:8080/?protocol=highestDeaths&username=Shimi&from=25-10-2021&to=28-10-2021"
    

  • Output:

    {
      "25-10-2021": "France",
      "26-10-2021": "France",
      "27-10-2021": "France",
      "28-10-2021": "France"
    }

Get the country (from the user's list) with the highest confirmed cases relative to the country population

Click to Expand

• Method: GET.
• Base: /?protocol=highestConfirmed.
• Required query parameters:
  • username: string of a username (no spaces, case insensitive).
  • from: string of the date format DD-MM-YYYY.
  • to: string of the date format DD-MM-YYYY.
• Return: JSON with which maps each date to his country.
• Example:
  • Input:

    curl "http://localhost:8080/?protocol=highestConfirmed&username=Shimi&from=25-10-2021&to=28-10-2021"
    

  • Output:

    {
      "25-10-2021": "France",
      "26-10-2021": "France",
      "27-10-2021": "France",
      "28-10-2021": "France"
    }

Further places to expand the project

• Expand the logging system (logger.js). Currently, it's in his bare bones.
  • Move all the error messages to be static in the logger to help with consistency.
• handlers.js is starting to become quit robust.
  • It would help to move the validation functions to a new file.
  • Maybe also the date related functions.
• Create a new module for the server protocol.
  • It will hold functions related to conversion between the protocol and other formats.
  • Keeping statically the protocol properties (like country).
• CovidTempDatabase.js does not merge the data from /history and /cases. It may be more convenient to merge them.
• UserDatabase.js is not persistent between shutdowns, it has the serialize & deserialize functions, but they are not utilized yet.
  • Worth changing this database to a persistent one like SQL, to avoid losing data between crushes.
• The server always works with root (/) path, it would be better to expand it to work with other paths too.
• Create test folder with automatic tests using curl.

Known bugs

• Any query which requires data on ranges of dates, does not work with the today date. It requires performing 2 queries to covid19-API, which it doesn't at the moment.

Credit

This project was written by @github/NineLord.