dash-core-components/lib/components/Download.react.js

Core component suite for Dash

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;
var _propTypes = _interopRequireDefault(require("prop-types"));
var _react = require("react");
var _base64Js = require("base64-js");
var _fileSaver = require("file-saver");
function _interopRequireDefault(e) { return e && e.__esModule ? e : { default: e }; }
var getValue = (src, fallback, key) => key in src ? src[key] : fallback[key];

/**
 * The Download component opens a download dialog when the data property changes.
 */
class Download extends _react.Component {
  componentDidUpdate(prevProps) {
    var data = this.props.data;
    // If the data hasn't changed, do nothing.
    if (!data || data === prevProps.data) {
      return;
    }
    // Extract options from data if provided, fallback to props.
    var type = getValue(data, this.props, 'type');
    var base64 = getValue(data, this.props, 'base64');
    // Invoke the download using a Blob.
    var content = base64 ? (0, _base64Js.toByteArray)(data.content) : data.content;
    var blob = new Blob([content], {
      type: type
    });
    (0, _fileSaver.saveAs)(blob, data.filename);
  }
  render() {
    return null;
  }
}
exports.default = Download;
Download.propTypes = {
  /**
   * The ID of this component, used to identify dash components in callbacks.
   */
  id: _propTypes.default.string,
  /**
   * On change, a download is invoked.
   */
  data: _propTypes.default.exact({
    /**
     * Suggested filename in the download dialogue.
     */
    filename: _propTypes.default.string.isRequired,
    /**
     * File content.
     */
    content: _propTypes.default.string.isRequired,
    /**
     * Set to true, when data is base64 encoded.
     */
    base64: _propTypes.default.bool,
    /**
     * Blob type, usually a MIME-type.
     */
    type: _propTypes.default.string
  }),
  /**
   * Default value for base64, used when not set as part of the data property.
   */
  base64: _propTypes.default.bool,
  /**
   * Default value for type, used when not set as part of the data property.
   */
  type: _propTypes.default.string,
  /**
   * Dash-supplied function for updating props.
   */
  setProps: _propTypes.default.func
};
Download.defaultProps = {
  type: 'text/plain',
  base64: false
};