TypeScript NodeJS websocket client

install

npm i websocket @types/websocket

usage

共通化

const websocket = <T>(url: string, onmessage: (t: T) => void, onerror?: (e: any) => void, onclose?: () => void) => {
    const webClient = require("websocket").client
    const client: client = new webClient()
    client.on('connect', (con: connection) => {
        console.log(`connected ${con.connected}`)
        con.on('error', (e: any) => console.error(e))
        con.on('close', () => console.log("websockets closed."))
        con.on('message', (message: Message) => {
            if (message.type === "utf8") {
                const t = JSON.parse(message.utf8Data) as T
                onmessage(t)
            }
        })
        if (onerror) {
            con.on('error', onerror)
        }
        if (onclose) {
            con.on('close', onclose)
        }
    })
    client.connect(url)
}

利用例

この例では、仮想通貨取引所binanceへbtcusdt, xrpusdtの約定データをサブスクライブしている。

interface AggTrade {
    e: string
    E: number
    a: number
    s: string
    p: string
    q: string
    f: number
    l: number
    T: number
    m: boolean
}

function test(){
    websocket<AggTrade>("wss://fstream.binance.com/ws/" + "btcusdt@aggTrade", t => console.log(`Pare:${t.s}`))
    websocket<AggTrade>("wss://fstream.binance.com/ws/" + "xrpusdt@aggTrade", t => console.log(`Pare:${t.s}`))
    return
}
test()

実行結果

Pare:BTCUSDT
Pare:BTCUSDT
Pare:BTCUSDT
Pare:XRPUSDT
Pare:BTCUSDT
Pare:BTCUSDT
Pare:BTCUSDT
Pare:BTCUSDT
Pare:BTCUSDT
Pare:XRPUSDT
Pare:XRPUSDT
Pare:XRPUSDT
Pare:BTCUSDT

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