Madonna Map

Creates a function that validates its arguments via madonna-fp before mapping them to something else. I created this to validate raw json then map it through a class or constructor. Note madonna-map only allows you to map top-level properties. Allowing otherwise would create for unnecessarily complex code.

Tested against

• node 0.10.0 for the (default) es5 version
• node 6.0.0 for es6 @ require('madonna-map/es6')

Table of Contents

• Examples
• API

Examples

const madonnaMap = require('madonna-map');

// creates a function requiring the argument 'name' and maps its value to uppercase
let mapperFn = madonnaMap.createMapper({
  marg: { name: ['require', 'isLadenString'] }
  , argMap: { name: fp.toUpper }
});

mapperFn({ name: 'phil' });
// returns
// { name: 'PHIL' }


mapperFn({ name: {} });
// throws an error
// Invalid Input: The following arguments didn't pass their criterion
// invalid arguments and values: {
//   "name": {}
// }
// failed criterion per argument: {
//   "name": {
//     "flags": [
//       "isLadenString"
//     ]
//   }
// }


// don't mismatch the argMap property names with those declared in marg
mapperFn = madonnaMap.createMapper({
  marg: { name: ['require', 'isLadenString'] }
  , argMap: { notName: fp.toUpper }
});
// throws an error
// Invalid Input: argMap can only contain keys present in schema.
// invalid keys: notName
// keys allowed: name


// a slightly larger example
mapperFn = madonnaMap.createMapper({
  marg: {
    name: ['require', 'isLadenString']
    , age: { betweenI: [0, 120] }
  }
  , argMap: { name: fp.toUpper }
});

mapperFn({
  name: 'phil'
  , age: 28
});
// returns
// { name: 'PHIL', age: 28 }

API

require('madonna-map').createMapper

• Takes the following arguments
  • marg: require isLadenPlainObject
    • marg stands for 'madonna-fp argument'. It is passed to madonna-fp which is used to validate the arguments in calls to the returned function.
  • argMap: require isLadenPlainObject
    • This object can only contain keys found in marg and their values must be functions. Valid input will pass through these functions and returned. Not all properties in marg have to be mapped.
• Returns a function that validates its input against marg. Any properties in argMap will pass through their mappers. All validated arguments will be returned.