I can't seem to find any good example of server sent events.
My goal is to send 2 messages to 2 separate divs but i'm new with javascript so i don't know how to parse these two messages, can anyone point me in right direction?
And if someone can explain me how SSE works, can I run this php script send.php
to push updates to web page or javascript runs script itself?
Here is my PHP code:
<?php
header('Content-Type: text/event-stream');
header('Cache-Control: no-cache');
$message = $row['message'];
$user = $row['user'];
echo "{$message}
";
echo "{$user}
";
flush();
?>
And this is my HTML/Javascript:
<div id="result"></div>
<script>
if(typeof(EventSource)!=="undefined")
{
var source=new EventSource("send.php");
source.onmessage=function(event)
{
document.getElementById("result").innerHTML+=event.data + "<br>";
};
}
else
{
document.getElementById("result").innerHTML="Sorry, your browser does not support server-sent events...";
}
</script>
You can just send the events back to the server as a JSON encoded string and indicate which div should get what message.
$arr = array(
'user' => $row['user'],
'message' => $row['message']
)
echo json_encode($arr);
Then, parse the JSON response from the server and perform logic against it. Let's assume the two divs have an ID of user
and message
source.onmessage=function(event){
var $data = JSON.parse(event.data);
for(key in obj){
if (obj.hasOwnProperty(key)) { //ensure that we're not up in the prototype chain
document.getElementById(key).innerHTML = $data[key];
}
}
}
The relationship here is of course that key
will be either user
or message
. We also expect there to be 2 divs, id="user"
and id="message"
that we can modify the innerHTML for. This is not a requirement, but aids in simplifying the process.