How to call agent link without actually opening the page in the browser?

Agent Code
1

I am following the ‘Agent’ tutorial, to make a LED blink by calling an agent URL.
So far everything is working. When you open this link, my green LED will blink:

https://agent.electricimp.com/T____XoF?green=1

This is very cool indeed!
Of course, I don’t want my end users to open an empty HTML page, so I tried calling this URL invisibly by using jQuery.
Sadly this results in the following error:

No ‘Access-Control-Allow-Origin’ header is present on the requested resource.

My code:

$.get( "https://agent.electricimp.com/T____XoF?green=1", function( data ) { alert( "Imp url was called." ); });

Is there a way to call agent urls invisibly, without cross-domain errors?

2

@ElectricEerk, you may want to edit your post to remove the agent URL if (a) it’s genuine and (b) you don’t want the rest of us to access it!

3

You can use PHP CURL method.

I’m not sure how much PHP experience you have, or if you have a normal shared webhost that allows PHP.

I usually use JQuery /AJAX with PHP handling the POST using CURL. This also fits well with JSON as both the imp and PHP make encode/decode rather easy.

There are examples … one of which is the instructable here:

See steps 5 and 6

4
Is there a way to call agent urls invisibly, without cross-domain errors?

This is because of security rules in browsers. If you add an “Access-Control-Allow-Origin” header to the response, you can call it from your webpage:

`function requestHandler(request, response) {
try {

// add access control allow origin so we can make AJAX requests to this endpoint
response.header("access-control-allow-origin", "*");

// check if the user sent led as a query parameter
if ("led" in request.query) {
  // if they did, and led=1.. set our variable to 1
  if (request.query.led == "1" || request.query.led == "0") {
    // convert the led query parameter to an integer
    local ledState = request.query.led.tointeger();

    // send "led" message to device, and send ledState as the data
    device.send("led", ledState); 
  }
}
// send a response back saying everything was OK.
response.send(200, "OK");

} catch (ex) {
response.send(500, "Internal Server Error: " + ex);
}
}

5

Thanks for all the tips, I was able to get my online moodlamp colorpicker working!
I now use the above mentioned PHP script so that the agent link is not visible to the end user.