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    flatley

    5.2.0 • Public • Published

    flatley Build Status

    Take a nested Javascript object and flatten it, or unflatten an object with delimited keys.

    Credits

    Based on 'flat' by Hugh Kennedy (http://hughskennedy.com)

    Installation

    $ npm install flatley

    Methods

    flatten(original, options)

    Flattens the object - it'll return an object one level deep, regardless of how nested the original object was:

    var flatten = require('flatley')
     
    flatten({
        key1: {
            keyA: 'valueI'
        },
        key2: {
            keyB: 'valueII'
        },
        key3: { a: { b: { c: 2 } } }
    })
     
    // {
    //   'key1.keyA': 'valueI',
    //   'key2.keyB': 'valueII',
    //   'key3.a.b.c': 2
    // }

    unflatten(original, options)

    Flattening is reversible too, you can call flatten.unflatten() on an object:

    var unflatten = require('flatley').unflatten
     
    unflatten({
        'three.levels.deep': 42,
        'three.levels': {
            nested: true
        }
    })
     
    // {
    //     three: {
    //         levels: {
    //             deep: 42,
    //             nested: true
    //         }
    //     }
    // }

    Options

    delimiter

    Use a custom delimiter for (un)flattening your objects, instead of ..

    safe

    When enabled, both flat and unflatten will preserve arrays and their contents. This is disabled by default.

    var flatten = require('flatley')
     
    flatten({
        this: [
            { contains: 'arrays' },
            { preserving: {
                  them: 'for you'
            }}
        ]
    }, {
        safe: true
    })
     
    // {
    //     'this': [
    //         { contains: 'arrays' },
    //         { preserving: {
    //             them: 'for you'
    //         }}
    //     ]
    // }

    object

    When enabled, arrays will not be created automatically when calling unflatten, like so:

    unflatten({
        'hello.you.0': 'ipsum',
        'hello.you.1': 'lorem',
        'hello.other.world': 'foo'
    }, { object: true })
     
    // hello: {
    //     you: {
    //         0: 'ipsum',
    //         1: 'lorem',
    //     },
    //     other: { world: 'foo' }
    // }

    overwrite

    When enabled, existing keys in the unflattened object may be overwritten if they cannot hold a newly encountered nested value:

    unflatten({
        'TRAVIS': 'true',
        'TRAVIS_DIR': '/home/travis/build/kvz/environmental'
    }, { overwrite: true })
     
    // TRAVIS: {
    //     DIR: '/home/travis/build/kvz/environmental'
    // }

    Without overwrite set to true, the TRAVIS key would already have been set to a string, thus could not accept the nested DIR element.

    This only makes sense on ordered arrays, and since we're overwriting data, should be used with care.

    maxDepth

    Maximum number of nested objects to flatten.

    var flatten = require('flatley')
     
    flatten({
        key1: {
            keyA: 'valueI'
        },
        key2: {
            keyB: 'valueII'
        },
        key3: { a: { b: { c: 2 } } }
    }, { maxDepth: 2 })
     
    // {
    //   'key1.keyA': 'valueI',
    //   'key2.keyB': 'valueII',
    //   'key3.a': { b: { c: 2 } }
    // }

    coercion

    Optionally run a test/set of tests on your incoming key/value(s) and transform the resulting value if it matches.

    This is particularly useful in the case of transforming https://www.npmjs.com/package/mongoose ObjectIds

    var ObjectId = mongoose.Types.ObjectId
     
    var coercion = [{
        test: function (key, value) { return key === '_id' && ObjectId.isValid(value) }
        transform: function (value) { return value.valueOf() }
    }]
    var options = { coercion: coercion }
     
    flatten({
        group1: {
            prop1: ObjectId('aaabbbcccdddeee')
        }
    }, options)
     
    // {
    //    'group1.prop1': 'aaabbbcccdddeee'
    // }

    filtering

    Optionally run a test/set of tests on your incoming key/value(s) and don't transform this key's children if it matches.

     
    const someObject = {
        prop1: 'abc',
        prop2: 'def'
    }
     
    var filters = [{
        test: function (key, value) { return value.prop1 === 'abc' }
    }]
    var options = { filters: filters }
     
    flatten({
        group1: {
            someObject: someObject
        }
    }, options)
     
    // {
    //    'group1.someObject': {
    //      'prop1': 'abc',
    //      'prop2': 'def'
    //    }
    // }

    Install

    npm i flatley

    DownloadsWeekly Downloads

    2,318

    Version

    5.2.0

    License

    BSD-3-Clause

    Unpacked Size

    25.5 kB

    Total Files

    6

    Last publish

    Collaborators

    • antony