How to get session from an App Extension (Bulk action link)

Shopify Apps
1

Hi,

I have a Node.js app created with the Shopify CLI. I added an app extension for the bulk actions on the order page, however once I receive the request. I get the information but I cannot load the the current session to then access the Graphql API.

app.get("/extension/orders/bulk", async(req, res) => {
    console.log(req.query);
// Outputs
// {
    //   ┃   hmac: '111a4...',
    //   ┃   host: 'dGVz...',
    //   ┃   ids: ['4381574332601', '4381574070457', '4381573873849'],
    //   ┃   locale: 'en-CA',
    //   ┃   session:'2a1f891...',
    //   ┃   shop: 'tester12auth.myshopify.com',
    //   ┃   timestamp: '1650849240'
    //   ┃
    // }

    res.redirect(`/?shop=${req.query.shop}&host=${req.query.host}`);
    const session = await Shopify.Utils.loadCurrentSession(req, res, true);
    console.log(session); // Undefined

  })

How can I get the current session from an App extension call. There is no session token in the headers.

Thanks