How to emit empty data

[BenLocal]

in js socketio can emit only event id data , like .emit("init-room"), then will send package like 42["init-room"]. but in socketioxide must send a serde_json::Value data. how can i emit be like js send a empty data

[Totodore]

Interesting, I didn't think about this.
As you can see in some examples you have to put your data in an array/tuple if you want to match the multi argument pattern in the js lib. More concretely something like this in js:
socket.emit("event", "arg1", "arg2") correspond to this with socketioxide socket.emit("event", ("arg1, "arg2")).

If you want to send nothing you can try to put an empty tuple () or an empty array [].

[BenLocal]

I am try send tuple () or an empty array [],but all not get expect package.
eg:
emit("init-room", ()) => ["init-room", null]
emit("init-room", [(); 0]) => ["init-room", []]

If bin(bytes).emit("init-room", ()) or bin(bytes).emit("init-room", [(); 0]) are sent together, the order in which the client obtains parameters may change.
eg in js socketio server: .emit("init-room", bytes), js can send package ["init-room",{"_placeholder":true,"num":0}]
and client can get args like: on("init-room", (bytes) => { ... })

[BenLocal]

I think the data type in packet::PacketData::Event and packet::BinaryPacket can change from Value to Option<Value>
If Option::None is emit, and skip json serialize it

[tausifcreates]

This sounds like a Good idea to me. Let's see what Theo thinks about this.

[Totodore]

If bin(bytes).emit("init-room", ()) or bin(bytes).emit("init-room", [(); 0]) are sent together, the order in which the client obtains parameters may change. eg in js socketio server: .emit("init-room", bytes), js can send package ["init-room",{"_placeholder":true,"num":0}] and client can get args like: on("init-room", (bytes) => { ... })

It is not very clear, it may help you to know that binary packets are always pushed at the end of the payload. If someone would like to add this info to the doc feel free to make a PR :).

I am try send tuple () or an empty array [],but all not get expect package.
eg:
emit("init-room", [(); 0]) => ["init-room", []]

It is not possible to change from Value to Option<Value> to because the emit fn take a Serializable arg so it would force anyone to do Some(data) for each call.
The only solution would be to switch from this emit("init-room", [(); 0]) => ["init-room", []] to this emit("init-room", [(); 0]) => ["init-room"] which is completely doable but then it would become impossible to put empty arrays. A better thing to do would be to replace this one emit("init-room", ()) => ["init-room", null] to emit("init-room", ()) => ["init-room"].

In any case someone is going to complain that null / undefined / [] is not supported.

[tausifcreates]

The last line had me rolling 🤣