hyperapp-v2-fx.js

const randomEffect = (props, dispatch) => {
  const randomValue = Math.random() * (props.max - props.min) + props.min;
  dispatch(props.action, randomValue)
};

export const Random = ({ action, min = 0, max = 1 }) => ({
  props: {
    action,
    min,
    max
  },
  effect: randomEffect
});

const httpEffect = (props, dispatch) => {
  fetch(props.url, props)
    .then(function(response) {
      if (!response.ok) {
        throw response;
      }
      return response;
    })
    .then(function(response) {
      return response[props.response]();
    })
    .then(function(result) {
      dispatch(props.action, result);
    })
    .catch(function(error) {
      dispatch(props.error, error);
    });
};

export const Http = options => ({
  props: {
    response: "json",
    error: options.action,
    ...options
  },
  effect: httpEffect
});

const webSocketEffect = (props, dispatch) => {
  const socket = new WebSocket(props.url);
  if (props.onOpenMessage) {
    socket.onopen = () => {
      socket.send(props.onOpenMessage);
    };
  }
  socket.onmessage = dispatch.bind(null, props.action);
  return () => {
    socket.close();
  };
};

export const WebSocketClient = props => ({
  props,
  effect: webSocketEffect
});