haraka-notes/index.js

Haraka Notes

class Notes {
  constructor(notes) {
    if (notes && typeof notes === 'object') {
      Object.assign(this, notes)
    }

    Object.defineProperty(this, 'set', {
      configurable: false,
      enumerable: false,
      writable: false,
      value: assignPathValue.bind(this),
    })

    Object.defineProperty(this, 'get', {
      configurable: false,
      enumerable: false,
      writable: false,
      value: getPathValue.bind(this),
    })
  }
}

module.exports = Notes

function getSegments(path) {
  // a dot.delimited.path
  if (typeof path === 'string') return path.split('.')

  // ['one', 'two', 'thr.ee']
  if (Array.isArray(path)) return path
}

function assignPathValue(path, value, onlyWhenUndefined) {
  if (path === undefined || value === undefined) return

  const segments = getSegments(path)
  let dest = this

  while (segments.length > 1) {
    // create any missing paths
    if (!dest[segments[0]]) dest[segments[0]] = {}
    // set dest one path segment deeper
    dest = dest[segments.shift()]
  }
  if (onlyWhenUndefined) {
    if (dest[segments[0]] === undefined) dest[segments[0]] = value
  } else {
    dest[segments[0]] = value
  }
}

function getPathValue(path) {
  if (!path) return
  const segments = getSegments(path)
  return segments.reduce((prev, curr) => {
    return prev ? prev[curr] : undefined
  }, this)
}