Server-Sent Events|A server-sent event is when a web page automatically gets updates from a server for construct3
This was also possible before, but the web page would have to ask if any updates were available. With server-sent events, the updates come automatically.
Examples: Facebook/Twitter updates, stock price updates, news feeds, sport results, etc. ///////////////////////////////////////////// construct3
conditions: onerror:When an error occurs onopen:When a connection to the server is opened onmessage:When a message is received
actions: connect:Server-Sent Events(SSE) connect to url Support:check browser support for server-sent events(SSE)
expressions: data:data callback url error:error ////////////////////////////////////////////////// server
For the example above to work, you need a server capable of sending data updates.
The server-side event stream syntax is simple. Set the "Content-Type" header to "text/event-stream". Now you can start sending event streams. Example:
php code:
header('Content-Type: text/event-stream');
header('Cache-Control: no-cache');
$time = date('r');
echo "data: The server time is: {$time}\n\n";
Controlling the Reconnection-timeout The browser attempts to reconnect to the source roughly 3 seconds after each connection is closed. You can change that timeout by including a line beginning with "retry:", followed by the number of milliseconds to wait before trying to reconnect.
The following example attempts a reconnect after 10 seconds:
php code:
retry: 10000\n
Example:
php code:
header('Access-Control-Allow-Origin: *');
header('Content-Type: text/event-stream');
echo "retry: 10000\n";
$time = date('r');
echo "data: The server time is: {$time}\n\n";