react-static/lib/client/components/PrefetchWhenSeen.js

A progressive static site generator for React

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});

var _regenerator = require('babel-runtime/regenerator');

var _regenerator2 = _interopRequireDefault(_regenerator);

var _extends = Object.assign || function (target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i]; for (var key in source) { if (Object.prototype.hasOwnProperty.call(source, key)) { target[key] = source[key]; } } } return target; };

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

var _react = require('react');

var _react2 = _interopRequireDefault(_react);

var _shared = require('../../utils/shared');

var _methods = require('../methods');

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function _objectWithoutProperties(obj, keys) { var target = {}; for (var i in obj) { if (keys.indexOf(i) >= 0) continue; if (!Object.prototype.hasOwnProperty.call(obj, i)) continue; target[i] = obj[i]; } return target; }

function _asyncToGenerator(fn) { return function () { var gen = fn.apply(this, arguments); return new Promise(function (resolve, reject) { function step(key, arg) { try { var info = gen[key](arg); var value = info.value; } catch (error) { reject(error); return; } if (info.done) { resolve(value); } else { return Promise.resolve(value).then(function (value) { step("next", value); }, function (err) { step("throw", err); }); } } return step("next"); }); }; }

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

function _possibleConstructorReturn(self, call) { if (!self) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return call && (typeof call === "object" || typeof call === "function") ? call : self; }

function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function, not " + typeof superClass); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }

var ioIsSupported = typeof window !== 'undefined' && 'IntersectionObserver' in window;
var handleIntersection = function handleIntersection(element, callback) {
  var io = new window.IntersectionObserver(function (entries) {
    entries.forEach(function (entry) {
      // Edge doesn't support isIntersecting. intersectionRatio > 0 works as a fallback
      if (element === entry.target && (entry.isIntersecting || entry.intersectionRatio > 0)) {
        io.unobserve(element);
        io.disconnect();
        callback();
      }
    });
  });

  io.observe(element);
};

var PrefetchWhenSeen = function (_React$Component) {
  _inherits(PrefetchWhenSeen, _React$Component);

  function PrefetchWhenSeen() {
    var _ref,
        _this2 = this;

    var _temp, _this, _ret;

    _classCallCheck(this, PrefetchWhenSeen);

    for (var _len = arguments.length, args = Array(_len), _key = 0; _key < _len; _key++) {
      args[_key] = arguments[_key];
    }

    return _ret = (_temp = (_this = _possibleConstructorReturn(this, (_ref = PrefetchWhenSeen.__proto__ || Object.getPrototypeOf(PrefetchWhenSeen)).call.apply(_ref, [this].concat(args))), _this), _this.runPrefetch = function () {
      return _asyncToGenerator( /*#__PURE__*/_regenerator2.default.mark(function _callee() {
        var _this$props, path, onLoad, type, cleanedPath, data;

        return _regenerator2.default.wrap(function _callee$(_context) {
          while (1) {
            switch (_context.prev = _context.next) {
              case 0:
                _this$props = _this.props, path = _this$props.path, onLoad = _this$props.onLoad, type = _this$props.type;
                cleanedPath = (0, _shared.cleanPath)(path);
                _context.next = 4;
                return (0, _methods.prefetch)(cleanedPath, { type: type });

              case 4:
                data = _context.sent;

                onLoad(data, cleanedPath);

              case 6:
              case 'end':
                return _context.stop();
            }
          }
        }, _callee, _this2);
      }))();
    }, _this.handleRef = function (ref) {
      if (ioIsSupported && ref) {
        handleIntersection(ref, _this.runPrefetch);
      }
    }, _temp), _possibleConstructorReturn(_this, _ret);
  }

  _createClass(PrefetchWhenSeen, [{
    key: 'componentDidMount',
    value: function componentDidMount() {
      if (!ioIsSupported) {
        this.runPrefetch();
      }
    }
  }, {
    key: 'render',
    value: function render() {
      var _props = this.props,
          component = _props.component,
          render = _props.render,
          children = _props.children,
          rest = _objectWithoutProperties(_props, ['component', 'render', 'children']);

      if (component) {
        return _react2.default.createElement(component, {
          handleRef: this.handleRef
        });
      }
      if (render) {
        return render({ handleRef: this.handleRef });
      }
      return _react2.default.createElement(
        'div',
        _extends({ ref: this.handleRef }, rest),
        children
      );
    }
  }]);

  return PrefetchWhenSeen;
}(_react2.default.Component);

PrefetchWhenSeen.defaultProps = {
  children: null,
  path: null,
  className: null,
  type: null,
  onLoad: function onLoad() {}
};
exports.default = PrefetchWhenSeen;