apeman-app-json/lib/create.js

apeman app to serve dynamic json.

/**
 * @function apemanAppJson
 * @param {object} [options] - Optional settings.
 * @param {number} [options.spaces=2] - JSON spaces
 * @param {string} [options.contentType='application/json charset=UTF-8'] - Content type for header
 * @param {string} [options.name='json'] - Property name of response to set the function.
 * @returns {function} - Defined app function.
 */

'use strict'

/** @lends create */
function create (options = {}) {
  let spaces = options.spaces || 2
  let contentType = options.contentType || 'application/json charset=UTF-8'
  let name = options.name || 'json'

  function json (data) {
    if (typeof data === 'string') {
      data = JSON.parse(data)
    }
    const res = this
    let body = JSON.stringify(data, null, spaces)
    res.setHeader('Content-Length', Buffer.byteLength(body))
    res.setHeader('Content-Type', contentType)
    res.end(body)
  }

  /**
   * Defined app.
   * @function app
   * @param {object} req - Request object.
   * @param {object} res - Response object.
   * @param {function} next - Pass to next handler.
   */
  function app (req, res, next) {
    res[ name ] = res[ name ] || json
    next()
  }

  Object.assign(app, {
    // Description of this app.
    $desc: 'Define json response function.'
  })
  return app
}

module.exports = create