simple-object-mapper

Simple object key trasformation utility ~~for OCD~~

The problem

You want to rename the object keys of the data that you retrieved from your server.

This solution

This is a lightweight library to help you rename your object key to the convention that you desire.

Installation

This module is distributed via npm which is bundled with node and should be installed as one of your project's dependencies:

npm install --save simple-object-mapper

Usage

import { generateMapper, TransformType } from 'simple-object-mapper';

const schema = TransformType.camelCase;

const map = generateMapper(schema);

map({
  Id: 5,
  Name: 'SimpleObjectMapper',
  KeyWords: 'Awesome'
});

/* result: 
{
    id: 5,
    name: 'SimpleObjectMapper',
    keyWords: 'Awesome'
}
*/

API

TransformType

TransformType is the built in naming convention, which consists of camelCase TransformType.camelCase and PascalCase TransformType.PascalCase.

generateMapper: (schema: DataSchema) => function

The function you use to generate the mapping function. You need to provide the schema for you data as the input for this function.

(Schema)

In its simplest form, schema can be just the TransformType, e.g. const schema = TransformType.camelCase. However, this only works if your object is a simple key-value object. If your object has nested object/array, then you need to provide the full schema.

A full schema is defined as the following typescript interface. No worries if you are not familiar with typescript, each properties will be explained below.

interface FullSchema {
  transformType: TransformType;
  exclude?: string[];
  include?: string[];
  nestedObjKey?: {
    [key: string]: FullSchema | TransformType;
  };
  nestedArrayKey?: {
    [key: string]: FullSchema | TransformType;
  };
}

transformType: TransformType | required

The transformation convention that you want to apply, can be TransformType.camelCase or TransformType.PascalCase.

exclude: string[] | optional

The keys that you want to exclude from the transformation.

Example:

const oriData = {
  Id: 5,
  FullName: 'My Name'
};

const desiredData = {
  Id: 5,
  fullName: 'My Name'
};

const schemaToUse = {
  transformType: TransformType.camelCase,
  exclude: ['Id']
};

include: string[] | optional

The keys that you want to apply the transformation. include will be ignored if exclude is provided.

nestedObjKey: {[key: string]: Schema} | optional

The keys that has nested data that you wish to apply the transformation.

Example:

const oriData = {
  Id: 5,
  FullName: 'My Name',
  Address: {
    Street: 'Big Street',
    City: 'Kuala Lumpur',
    Country: 'Malaysia'
  }
};

const desiredData = {
  Id: 5,
  fullName: 'My Name',
  address: {
    street: 'Big Street',
    city: 'Kuala Lumpur',
    country: 'Malaysia'
  }
};

const schemaToUse = {
  transformType: TransformType.camelCase,
  exclude: ['Id'],
  nestedObjKey: {
    Address: {
      transformType: TransformType.camelCase
    }
  }
};

nestedArrayKey: {[key: string]: Schema} | optional

The keys that has nested array data that you wish to apply the transformation.

Example:

const oriData = {
  Id: 5,
  FullName: 'My Name',
  Contacts: [
    {
      Type: 'email',
      Value: '[email protected]'
    },
    {
      Type: 'phone',
      Value: '0103349585'
    }
  ]
};

const desiredData = {
  Id: 5,
  fullName: 'My Name',
  contacts: [
    {
      type: 'email',
      value: '[email protected]'
    },
    {
      type: 'phone',
      value: '0103349585'
    }
  ]
};

const schemaToUse = {
  transformType: TransformType.camelCase,
  exclude: ['Id'],
  nestedArrayKey: {
    Contacts: {
      transformType: TransformType.camelCase
    }
  }
};