Next Perpendicular Moonlanding

    secret-door

    1.1.2 • Public • Published

    secret-door

    secret-door is an RPC implementation on top of window.postMessage for cross context communication in the browser. It can be used, for example, to call functions in a cross domain iframe.

    secret-door returns promises when executing remote functions and therefore assumes that window.Promise is available.

    Install

    npm install --save secret-door

    Usage

    In parent window.

    var Channel = require("secret-door");
     
    var channel = new Channel({
      targetWindow: document.querySelectorAll(".some-iframe")[0].contentWindow
    }).setHandler({
      foo: function () {},
      bar: function () {}
    }, this);
     
    // set an additional handler
    channel.setHandler("getAnswer", function (arg1, arg2) {
      // we can return a promise
      return new Promise(function (resolve) {
        return doSomething(arg1 + arg2);
      })
    }, this)
     
    // set a catch all handler
    channel.setHandler("*", function (command, arg1, arg2, arg3) {
      // all remote command calls that don't have a registered
      // named handler can be handled here
    });
     
    // unset a handler
    channel.clearHandler("bar");
     
    //call a function within the iframe
    channel.execute("getURL").then(function (url) {
      console.log(url);
    });

    In an iframe.

    var channel = new Channel({
      targetWindow: window.parent
    }).setHandler({
      getURL: function () {
        return window.location.href;
      }
    });
    channel.execute("getAnswer", 2, 5).then(function (answer) {
      console.log(answer);
    });

    API

    var channel = new Channel(options)

    • options.targetWindow - The window to send messages to (e.g. iframeEl.contentWindow, window.parent)
    • options.targetOrigin - What the origin of the other window must be for sending messages
    • options.namespace - Allows using multiple instances of secret door on the same page
    • options.filterIncoming - A function that can reject an incoming message by inspecting parsed data and raw messageEvent

    channel.setHandler()

    channel.setHandler(name, fn, context);
    channel.setHandler(obj, context);

    Set the handler for incoming commands.

    The handler can be named via the first argument. e.g. channel.setHandler('foo', function () {});

    The handler can also be an object mapping names to functions. e.g. channel.setHandler({foo: function () {}, bar: function () {}});

    Both can be used in combination. Further calls to either will extend the list of channel's handlers.

    If a handler with that name already exists, it will be overwritten with the new one.

    The last argument can be used to pass the context that the handler functions will be applied in.

    To handle all incoming commands for which a named handler is not available, register a handler with name "". e.g. channel.setHandler('', function (command, arg1) { console.log('handling all commands')} );

    Handlers can return promises.

    channel.execute(fnName, ...args)

    Execute a function on the other side of the channel. First argument is the name of the remote function. The rest of the arguments will be passed as arguments to the remote function.

    channel.clearHandler(name)

    Remove a handler.

    channel.clearAllHandlers(name)

    Remove all handlers.

    Returns a promise.

    channel.tap(fn)

    Listen in on all requests/responses going through this channel. The callback will be called with 1 object describing the request or response. Only messages that actually go via the channel will be tapped, in other words if the message is in the wrong namespace, wrong origin or is filtered by filterIncoming it won't show up in the tap.

    channel.destroy()

    Remove handler references and stop listening to events.

    Test

    npm test
    

    Release

    npm run release
    

    Follow semver rules when specifying a new version.

    Keywords

    none

    Install

    npm i secret-door

    DownloadsWeekly Downloads

    2

    Version

    1.1.2

    License

    none

    Last publish

    Collaborators

    • qubit
    • oliverwoodings
    • alz