parseJSONSSE.ts

export const parseJsonSSE = async <T>({
    data,
    onParse,
    onFinish
}: {
    data: ReadableStream
    onParse: (object: T) => void
    onFinish: () => void
}) => {
    const reader = data.getReader()
    const decoder = new TextDecoder()

    let done = false
    let tempState = ""

    while (!done) {
        // eslint-disable-next-line no-await-in-loop
        const { value, done: doneReading } = await reader.read()
        done = doneReading
        const newValue = decoder.decode(value).split("\n\n").filter(Boolean)

        if (tempState) {
            newValue[0] = tempState + newValue[0]
            tempState = ""
        }

        // eslint-disable-next-line @typescript-eslint/no-loop-func
        newValue.forEach((newVal) => {
            try {
                const json = JSON.parse(newVal.replace("data: ", "")) as T

                onParse(json)
            } catch (error) {
                tempState = newVal
            }
        })
    }

    onFinish()
}