This little php script can be installed on a local webserver to forward http POST requests with JSON payload to a vdcd daemon which has a TCP socket JSON API.
To simplify testing, simple JSON requests that only consist of an object containing some fields (and no nested arrays or objects) can also be created as GET request with CGI style parameters in the URI.
(Note however that http GET requests are considered being safe or even idempotent, which means the browser may retry them, so even if the API forwarder would allow using GET requests for example to execute a callScene method call, this can lead to unexpected side effects when repeated and therefore POST should be used for any call that modifies properties or other state.)
Just install it on a webserver and make sure line 9 and 10 point to a running vdcd instance.