[QUESTION]: websocket usage for data updates #1590
Description
Hi there,
I’m experiencing an issue when trying to use the new WebSocket option in FUXA to update data more frequently than the 1-second interval provided by the WebAPI.
Here’s what I’ve done:
- Switched my WebAPI connection to an “internal” connection to retain the tags.
- Created a server-side script to fetch the initial data using the WebAPI.
- Set up the WebSocket connection to handle subsequent updates.
However, the behavior isn’t as expected. When fetching tag data by ID using $getTag(), it always returns null.
Example API Response:
From my WebAPI:
{
"t_8f60fd-f8073b": "1",
"t_cb52db-724556": "3",
"t_a2d094-5596cc": "1"
}
The WebSocket returns the following:
42/fuxa,
[
"fuxa-data",
{
"tagId": "t_9bece6-11c1c5",
"data": "-21.2713623046875"
}
]
When I try to then setTag(tagId, data) I always get setValue not supported!
Despite successfully retaining tag IDs and verifying their values using the template function $getTag(), attempting to access tags via $getTag('t_8f60fd-f8073b') consistently returns null.
console.log($getTag('t_8f60fd-f8073b' /* stHMIInterface - iCurrentUnit */));
Environment:
FUXA Version: 1.2.3
Expected Behavior:
- Only have an internal device with tags.
$setTagto set the data to a internal device tag to get rid of the webapi connection
Please let me know if I’m missing something in the setup or if this is a bug. Any guidance would be much appreciated!
Thank you!
Script that I configured as 1s startup delay on server:
const readDataFromWebsocket = () => {
// Handle successful connection
ws.on('open', () => {
console.log('WebSocket connection established');
ws.send('40/fuxa');
});
ws.on('message', (message) => {
try {
const messageStr = message.toString();
if (messageStr.startsWith('42/fuxa,')) {
const parsedData = JSON.parse(messageStr.slice(8)); // Strip off the socket prefix "42/fuxa"
const tagId = parsedData[1].tagId;
const value = parsedData[1].data;
console.log('tagId', tagId);
console.log('value', value);
$setTag(tagId, value);
} else {
console.log('Raw message:', messageStr);
}
} catch (error) {
console.log('Error processing message from WebSocket server:', error);
}
});
ws.on('error', (error) => {
console.log('WebSocket error:', error);
});
ws.on('close', () => {
console.log('WebSocket connection closed');
//TODO: Attempt to reconnect after a delay if the connection is closed
});
}
const getInitialFetchData = () => {
const options = {
hostname: hostname,
port: port,
path: getPath,
method: 'GET',
};
const req = http.request(options, (res) => {
let responseData = '';
res.on('data', (chunk) => {
responseData += chunk;
});
res.on('end', () => {
const data = JSON.parse(responseData);
if (data) {
Object.entries(data).forEach(([tagId, value]) => {
$setTag(tagId, value);
});
readDataFromWebsocket()
} else {
console.log('empty data');
}
});
});
req.on('error', (error) => {
console.log('Error');
console.log(JSON.stringify(error));
});
req.end();
}
getInitialFetchData()