JSPM

  • ESM via JSPM
  • ES Module Entrypoint
  • Export Map
  • Keywords
  • License
  • Repository URL
  • TypeScript Types
  • README
  • Created
  • Published
  • Downloads 1625
  • Score
    100M100P100Q111034F
  • License MIT

convert json object into a new formatted json object

Package Exports

  • json-mapper-json

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (json-mapper-json) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

json-mapper-json

Simple library to convert a json object into a new json object formatted by a template.

Installation

Install via npm:

$ npm install json-mapper-json

Documentation

Usage

const jsonMapper = require('json-mapper-json');

jsonMapper(json<Object>, template<Object>) => Promise

Template Syntax Explanations

{
  newFieldName1: {
    path: <String>, // required
    required: <Boolean> // not required, default `true`
    formatting: <Function> // optional (ex: function(value) {return value + '_formatted';})
    defaultValue: <AnyType> // optional
    type: <NativeType> // optional (ex: String, Number, Boolean, ...) (not supported yet)
    nested: { <Object> // optional
      newNestedFieldName: <String>,
      required: <Boolean> // not required, default `true`
      formatting: <Function> // optional
      defaultValue: <AnyType> // optional
      type: <NativeType> // optional (ex: String, Number, Boolean, ...) (not supported yet)
      nested: { <Object> // optional
        ...
      },
    },
  },
  newFieldName2: <String> // (it's the path, syntactic sugar for {path: ''})
  ...
}

Path Key Words

  • $root: give possibility to access the root given object in a nested path.
  • $item: give possibility to access of the all item of an array in a nested path.
  • $empty: give possibility to create skip path, to create empty object to be able to merge paths (see example).

Example

Basic

jsonMapper({
  field: 'value',
}, {
  'new_field': {
    path: 'field',
  },
}).then((result) => {
  /*
  result === {
    'new_field': 'value',
  }
  */
});

Basic with required

jsonMapper({
  field1: 'value1',
}, {
  'new_field1': {
    path: 'field1',
  },
  'new_field2': {
    path: 'field2',
    required: false,
  },
}).then((result) => {
  /*
  result === {
    'new_field1': 'value1',
  }
  */
});

Basic with defaultValue

jsonMapper({
  field1: 'value1',
}, {
  'new_field1': {
    path: 'field1',
  },
  'new_field2': {
    path: 'field2',
    defaultValue: 'default_value',
  },
}).then((result) => {
  /*
  result === {
    'new_field1': 'value1',
    'new_field2': 'default_value',
  }
  */
});
jsonMapper({
  field1: 'value1',
  nested: {
    field3: 'value3',  
  },
}, {
  'new_field1': {
    path: 'field1',
  },
  'new_field2': {
    path: 'field2',
  },
}).then((result) => {
  /*
  throw Error: Invalid path nested.field2 (field2)
  */
});

Basic with nested

jsonMapper({
  field1: {
    field2: {
      field3: 'value',
      field4: 'value4',
    },
  },
}, {
  'new_field': {
    path: 'field1.field2',
    nested: {
      'nested_field1': {
        path: 'field3',
      },
      'nested_field2': {
        path: 'field4',
      },
    },
  },
}).then((result) => {
  /*
  result === {
    'new_field': {
      'nested_field1': 'value',
      'nested_field2': 'value4',
    }
  }
  */
});

Basic with formatting

jsonMapper({
  field1: {
    field2: {
      field3: 'value',
    },
  },
}, {
  'new_field': {
    path: 'field1.field2.field3',
    formatting: (value) => {return value + '_formatted';},
  },
}).then((result) => {
  /*
  result === {
    'new_field': 'value_formatted',
  }
  */
});

Array

jsonMapper([{
  field: 'value1',
}, {
  field: 'value2',
}, {
  field: 'value3',
},
], {
  'new_field': {
    path: 'field',
  },
}).then((result) => {
  /*
  result === [
    {'new_field': 'value1'},
    {'new_field': 'value2'},
    {'new_field': 'value3'},
  ]
  */
});

Array with formatting

jsonMapper([{
  field: 'value1',
}, {
  field: 'value2',
}, {
  field: 'value3',
},
], {
  'new_field': {
    path: 'field',
    formatting: (value, index) => (`${value}_formatted_${index}`),
  },
}).then((result) => {
  /*
  result === [
    {'new_field': 'value1_formatted_0'},
    {'new_field': 'value2_formatted_1'},
    {'new_field': 'value3_formatted_2'},
  ]
  */
});

Usage of the syntactic sugar for path

jsonMapper({
  field: 'value',
}, {
  'new_field': 'field',
}).then((result) => {
  /*
  result === {
    'new_field': 'value',
  }
  */
});

Array with nested and path syntactic sugar

jsonMapper([{
  field: {'nested_field': 'value1'},
}, {
  field: {'nested_field': 'value2'},
}, {
  field: {'nested_field': 'value3'},
},
], {
  'new_field': {
    path: 'field',
    nested: {
      'new_nested_field': 'nested_field',
    },
  },
}).then((result) => {
  /*
  result === [
    {'new_field': {'new_nested_field': 'value1'}},
    {'new_field': {'new_nested_field': 'value2'}},
    {'new_field': {'new_nested_field': 'value3'}},
  ]
  */
});

Usage of the key word $root for path

jsonMapper({
  'content': {
    'result': [
      {
        'courseStatisticsDto': {
          'times': 3,
          'persons': 1,
          'courseCode': '',
        },
        'courseAddressDto': {},
        'endDate': 1460590552000,
        'startDate': 1460590552000,
        'name': 'Example Course',
      },
    ],
    'type': 'offline',
  },
}, {
  data: {
    path: 'content.result',
    nested: {
      name: 'name',
      code: 'courseStatisticsDto.courseCode',
      type: '$root.content.type',
    },
  },
}).then((result) => {
/*
  result === {
    'data': [{
      'name': 'Example Course',
      'code': '',
      'type': 'offline',
    }],
  }
*/
});

Usage of the key word $item for path

jsonMapper({
    hits: {
        total: 1,
        hits: [{
            _index: 'some_index',
            _type: 'some_type',
            _id: '123456',
            _score: 1,
            _source: {
                id: 123456
            },
        }],
    },
}, {
    hits: {
        path: 'hits.hits',
        nested: {
            id: '_source.id',
            type: {
                path: '$item',
                formatting: (value, index) => (`${value._index}/${value._type}/${index}`),
            },
        },
    },
}).then((result) => {
/*
  result === {
    'hits': [{
      'id': 123456,
      'type': 'some_index/some_type/0',
    }],
  }
*/
});

Usage of the key word $empty for path

jsonMapper({
  field1: {
    field2: {
      field3: 0
    },
    field4: {
      field5: ['value1', 'value2'],
    },
  },
}, {
  'new_field1': {
    path: 'field1',
    nested: {
      'new_field2': {
        path: '$empty',
        nested: {
          new_field3: {
            path: 'field2.field3'
          },
          new_field4: {
            path: 'field4.field5',
          },
        },
      },
    },
  },
}).then((result) => {
  /*
  {
    new_field1: {
      new_field2: {
        new_field3: 0,
        new_field4: ['value1', 'value2'],
      },
    },
  }
  */
});

## Note

this library is very usefull when you have well design models and have to communicate with horrible webservices.

## TODO

* manage `type` property

## Contributing

This project is a work in progress and subject to API changes, please feel free to contribute