what data type is your info lane (String or Value)? Based on the name I am guessing that you have a Value lane but are sending a String. If you are sending to a Value lane, then use
valuelane.set(swim.Value.fromAny("john")) instead. This will convert your string to a Swim Value.
let oldvalue = valueLane.get();
valueLane.set("john");
console.log(oldvalue);
oldvalue = valueLane.get();
console.log(oldvalue);Absent and then "john".
valueLane.get() returns the current value of that valueLane()
@ajay-gov got it. what im trying to achieve is, to get the old and new value on the client side.
on the server side,
@SwimLane("info")
ValueLane<String> info = this.<String>valueLane()
.didSet((newValue, oldValue) -> {
logMessage("`info` set to " + newValue + " from " + oldValue);
});this prints the old and new value every time i set a new value. like this, [/welcome/user]infoset to hello from world
but on client side,
.didSet((newValue, oldValue) => {
console.log("link watched info change to " + newValue + " from " + oldValue);
})this always comes as absent.
Maybe I'm understanding the purpose of value lane incorrectly?
@vishnuprasad73_twitter
const client = new swim.WarpClient();
let valueLane = client.downlinkValue()
.hostUri("warp://localhost:9001").nodeUri("/welcome/user").laneUri("info")
.didSet((newValue, oldValue) => {
console.log("link watched info change to " + newValue + " from " + oldValue);
})
.open();is all you need. Whenever the "info" lane for the node "/welcome/user" gets updated on the server then the didSet callback in the valueLane reference in the client should get invoked with the oldValue and the newValue. Are you not seeing this?
@ajay-gov i tried that. but when i set a new value, the callback im getting on the client side is,link watched info change to john from Value.absent()
i have the same callback on server side, which works correctly.
@SwimLane("info")
ValueLane<String> info = this.<String>valueLane()
.didSet((newValue, oldValue) -> {
logMessage("`info` set to " + newValue + " from " + oldValue);
});which logs out put as below,
[/welcome/user] `info` set to doe from john
i tried setting the value as @scottswim mentioned above,
valuelane.set(swim.Value.fromAny("john")) still it shows as absent on client side though
@ajay-gov
Sure, glad to hear that it works. A bit more detail- when you open a downlink the swim client establishes a connection to the server. The data is streamed from the server to the client using that connection. You may open multiple downlinks i.e to other nodes/lanes on the same host and the swim client will use the same connection to stream data to the different downlinks. However when you call
client.close the connection to the server is closed and all downlinks will stop getting the data from the server.
@vishnuprasad73_twitter we work with customer related data for our enterprise apps. We have built a couple of sample apps that use public data sources.
- Swim Transit (Repo for code here: https://github.com/swimos/transit) is a real-time application that uses bus location information from multiple cities in the US. The bus location is sent from sensors on these buses. The docs for their API is here: https://gist.github.com/grantland/7cf4097dd9cdf0dfed14. You can look at the https://github.com/swimos/transit code to see how you can create web-agents from it and then build a real-time streaming web application using those web agents from a REST API data source.
- Swim Flight Tracker is a real-time application that uses flight location information. The flight location information is available here: https://opensky-network.org/apidoc/
@vishnuprasad73_twitter We are working on moving the swim-core into Rust. Since Rust will run natively, we plan on supporting other language bindings into Rust. At that point you could use other languages on the server-side
@vishnuprasad73_twitter Glad you like swim! Please do spread the word.
you can find the source for the Flight Tracker demo here https://github.com/swimos/flight-tracker. It demos using both 3rd party APIs (OpenSky) as well as static CSV files. The project itself is split into 2 parts. The main webapp and a data simulator. The data simulator takes data from the APIs and CSV files and sends data into the main app in a timed way using swim command lanes. This allows for starting/stopping/replaying the data in the main app.
We also have a simpler demo where we use NodeJS to bridge sensor data from an Arduino into Swim. The code for that demo is here: https://github.com/swimos/plant-monitor
anyway, it's not a major issue, Chrome works fine
that is another good thing to add to the list however.
mobile support should be fairly easy to add.
if it can be of any help: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes#Browser_compatibility
really this is where things like babel are perfect, however i am not using it in the project because i wanted to keep things as simple as possible.
@Pasvaz thanks for pointing the issue with the flight tracker. traffic (https://github.com/swimos/traffic), transit (https://github.com/swimos/transit) work on safari and on android.
https://traffic.swim.ai/ and https://transit.swim.ai/ are the hosted versions of those repos respectively
just pushed some quick fixes for safari to github and the live demo site.