Filters

Filter out the required content from an array of objects based on a set of conditions with the help of a single function.

Getting Started

A single function is to be used to search for objects in an array of objects in which a key that is to be found exists or has a value that matches a certain criteria.

Note: The algorithm will not only search for a matching condition in the main object but also the nested objects.

Syntax

filter({key,value}<Object>, operation<string>, data<Array<Object>>);

Usage

There are three categories of filters that are being used based on the data type for which the filtering is to be done.

• Number Filters
• String Filters
• Date Filters

Below is the syntax of how to use the filter function for different data types.

1. Number Filters

   • Equality

       filter({key: x<string>, value: y<number>}, 'eq', data<Array<Object>>);
   

   • Less than

       filter({key: x<string>, value: y<number>}, 'lt', data<Array<Object>>);
   

   • Less than or equal

       filter({key: x<string>, value: y<number>}, 'lte', data<Array<Object>>);
   

   • Greater than

       filter({key: x<string>, value: y<number>}, 'gt', data<Array<Object>>);
   

   • Greater than or equal

       filter({key: x<string>, value: y<number>}, 'gte', data<Array<Object>>);
   

   • Between

       filter({key: x<string>, min: y<number>, max: z<number>}, 'between', data<Array<Object>>);
   

2. String Filters

   • Equality

       filter({key: x<string>, value: y<string>}, 'eq', data<Array<Object>>);
   

   • Contain Exactly

       filter({key: x<string>, value: y<string>}, 'ce', data<Array<Object>>);
   

   • Not Contain Exactly

       filter({key: x<string>, value: y<string>}, 'nce', data<Array<Object>>);
   

   • Is any of - key has a value which is equal to any of the values given as an input.

       filter({key: x<string>, value: y<Array<string>>}, 'anyof', data<Array<Object>>);
   

   • Is none of - key has a value which is equal to none of the values given as an input.

       filter({key: x<string>, value: y<Array<string>>}, 'noneof', data<Array<Object>>);
   

3. Date Filters

   • Equality

       filter({key: x<string>, value: y<string>}, 'eq', data<Array<Object>>);
   

   • Before

       filter({key: x<string>, value: y<string>}, 'before', data<Array<Object>>);
   

   • After

       filter({key: x<string>, value: y<string>}, 'after', data<Array<Object>>);
   

   • Between

       filter({key: x<string>, min: y<string>, max: z<string>}, 'between', data<Array<Object>>);
   

4. Boolean Filters

   • Equality

       filter({key: x<string>, value: y<boolean>}, 'eq', data<Array<Object>>);
   

5. Generic Filters

   • Known

       filter({key: x<string>}, 'known', data<Array<Object>>);
   

   • Unknown

       filter({key: x<string>}, 'unknown', data<Array<Object>>);
   
   

Built With

• Nodejs

Testing

For testing, open the terminal in the directory where the index file is and run the following command.

npm run test-watch

Authors

• Suyash Awasthi - Initial work - Filters

Guided by Praveen Bisht