normalise-request

normalise-request

Normalises API requests

Install

$ npm install --save normalise-request

You can include this module using CommonJS format (require) or ES6 format (import):

const normalise = require('normalise-request');

// or

import normalise from 'normalise-request';

The examples in this README file are in CommonJS format.

Usage

Simple Objects

The most basic usage is normalising a simple object:

const normalise = require('normalise-request');

const request = {
    name: '   Steve   ',
    address: '  The Locksfords   '
};

const normaliser = {
    name: {
        trim: true
    },
    address: {
        trim: true
    }
};

normalise(request, normaliser);

// request.name is now 'Steve'
// request.address is now 'The Locksfords'

Normalisers are applied in declaration order:

// Example One:

const request = {
    name: '      ',
};

const normaliser = {
    name: {
        trim: true,
        undefinedIfEmpty: true
    }
};

normalise(request, normaliser);

// request.name is now undefined

// Example Two:

const request = {
    name: '      ',
};

const normaliser = {
    name: {
        undefinedIfEmpty: true,
        trim: true
    }
};

normalise(request, normaliser);

// request.name is now '' (the empty string)

Nested Objects

const normalise = require('normalise-request');

const request = {
    name: '   Steve   ',
    address: {
        firstLine: '  The Locksfords  ',
        secondLine: ' London '
    }
};

const normaliser = {
    name: {
        trim: true
    },
    address: {
        object: {
            firstLine: { trim: true },
            secondLine: { trim: true }
        }
    }
};

normalise(request, normaliser);

// request.name is now 'Steve'
// request.address.firstLine is now 'The Locksfords'
// request.address.secondLine is now 'London'

Arrays of Primitive Types

const normalise = require('normalise-request');

const request = {
    tags: ['  art  ', '   theatre   ']
};

const normaliser = {
    tags: {
        each: {
            trim: true
        }
    }
};

normalise(request, normaliser);

// request.tags[0] is now 'art'
// request.tags[1] is now 'theatre'

Arrays of Objects

const normalise = require('normalise-request');

const request = {
    tags: [
        { label: '  art  ' },
        { label: '   theatre   '}
    ]
};

const normaliser = {
    tags: {
        each: {
            object: {
                label: {
                    trim: true
                }
            }
        }
    }
};

normalise(request, normaliser);

// request.tags[0].label is now 'art'
// request.tags[1].label is now 'theatre'

Adding a new normaliser

const normalise = require('normalise-request');

const changeToFoo = (param, options) => {
    // param - the value this normaliser is being applied to.
    // options - the object assigned to the normaliser 
    return 'foo';
};

normalise.normalisers.changeToFoo = changeToFoo;

// use it like a built-in normaliser:

const normaliser = {
    name: {
        changeToFoo: { someOption: 'value' }
    }
}

// name will become 'foo'

API

normalise(object, normaliser)

Mutates object to normalise it according to the normaliser.

object

Type: Object

The object to normalise.

normaliser

Type: Object

The normaliser object that specifies the normalisations to apply to the object.

Normalisers

trim

Trims the value to normalise if it is a string.

const normaliser = {
    name: {
        trim: true
    }
};

toUpperCase

Uppercases the value to normalise if it is a string.

const normaliser = {
    name: {
        toUpperCase: true
    }
};

toLowerCase

Lowercases the value to normalise if it is a string.

const normaliser = {
    name: {
        toLowerCase: true
    }
};

undefinedIfEmpty

Sets the value to normalise to undefined if it is a zero-length string or a zero-length array, or if the value is null.

const normaliser = {
    name: {
        undefinedIfEmpty: true
    }
};

collapseWhitespace

Collapses whitespace in the value to normalise if it is a string. Any runs of multiple whitespace characters are each replaced by a single space character. If using this normaliser on a value, you would normally also use the trim normaliser.

const normaliser = {
    name: {
        collapseWhitespace: true
    }
};

replace

Replaces matching strings in the value to normalise, if that value is a string. This normaliser uses the String.replace method to do the replacement, so the arguments to this normaliser and its behaviour correspond to those of that string method:

• pattern can be a string or a regex
• newSubStr is the replacement string

const normaliser = {
    name: {
        replace: { pattern: /H/g, newSubStr: 'Y'}
    }
};

toFloat

Converts the value to normalise to a float number, if that value is a string.

const normaliser = {
    name: {
        toFloat: true
    }
};

toInt

Converts the value to normalise to an integer number, if that value is a string.

const normaliser = {
    name: {
        toInt: true
    }
};

default

Sets the value to normalise to a replacement value, if that value to normalise is null or undefined.

const normaliser = {
    name: {
        default: { value: 'the default value' }
    }
};

// or

const normaliser = {
    name: {
        default: 'the default value'
    }
};

decodeAsUriComponent

Converts the value to normalise using the decodeAsUriComponent global method, if that value is a string.

const normaliser = {
    name: {
        decodeAsUriComponent: true
    }
};

split

Converts the value to normalise using the string.split method, if that value is a string. The argument to the normaliser is the separator string for the split.

const normaliser = {
    name: {
        split: { separator: ',' }
    }
};

// or 

const normaliser = {
    name: {
        split: ','
    }
};

License

MIT

Acknowledgements

This package was influenced by the package Validate.js.