postmanSessionAuth.js

const URL = "http://localhost:8000/"
const USERNAME = "client"
const PASSWORD = "client"
let AUTH = false
 
 
const cookieJar = pm.cookies.jar();
 
const getCSRFToken = () => {
    pm.sendRequest("http://localhost:8000/login/", (error, response) => {
    })
}
 
const auth = () => {
    cookieJar.get(URL, "csrftoken", (error, cookie) => {
        const creds = {
            password: PASSWORD,
            username: USERNAME,
        }
        const postRequest = {
            url: "http://localhost:8000/api/signin/",
            method: 'POST',
            body: JSON.stringify(creds),
            header: {
                'Content-Type': 'application/json',
                'X-CSRFToken': cookie
            }
        };
 
        pm.sendRequest(postRequest, (error, response) => {
            console.log(error ? error : response.code);
        });
    })
}
 
const checkAuth = () => {
    const callback = (error, cookies) => {
        names = cookies.map(cookie => cookie.name)
        AUTH = ['csrftoken', 'sessionid'].some(name => names.includes(name))
    }
 
    cookieJar.getAll(URL, callback);
}
 
const isAuthorized = () => {
    if (AUTH) return true
    getCSRFToken()
}
 
const interval = setInterval(() => {}, Number.MAX_SAFE_INTEGER)
 
const delay_fn = (...params) => (
    new Promise((resolve, reject) => {
        setTimeout(() => resolve(params), 50)
    })
)
 
// главная логика
const run = async () => {
    checkAuth()
    let arr1 = await delay_fn(1)
    if (!isAuthorized()) {
        let arr2 = await delay_fn(2)
        auth()
    }
}
 
(async () => {
    try {
        await run()
    } finally {
        clearInterval(interval)
    }
})()