dataloader-example.js

const Dataloader = require("dataloader")
const fakeAsync = (content, t) => new Promise(res => setTimeout(_ => {
    console.log("content:", content)
    content = content.map(c => c + 1)
    res(content)
}, t))

async function start() {
    const testLoader = new Dataloader(async (keys) => {
        console.log("batched by dataloader: ", keys)
        let res = await fakeAsync(keys)
        return res.map(r => Promise.resolve(r))
    })

    // 1,2,3 should be batch
    testLoader.load(1).then(t => console.log("1 got ", t))
    testLoader.loadMany([2, 3]).then(t => console.log("[2,3] got ", t))

    // 4 should be seperate
    setTimeout(() => {
        testLoader.load(4)
    })
    Promise.resolve().then(()=>{
        testLoader.load(5)
    })
}

start()