next.js/examples/with-temporal/pages/api/orders/index.ts

import { NextApiRequest, NextApiResponse } from "next";
import { WorkflowClient } from "@temporalio/client";
import { order } from "../../../temporal/src/workflows";

export type Data = {
  result: string;
};

function getUserId(token?: string): string {
  // TODO if the token is a JWT, decode & verify it. If it's a session ID,
  // look up the user's ID in the session store.
  return "user-id-123";
}

export default async function handler(
  req: NextApiRequest,
  res: NextApiResponse<Data>,
) {
  if (req.method !== "POST") {
    res.send({ result: "Error code 405: use POST" });
    return;
  }

  const userId: string = getUserId(req.headers.authorization);
  const { itemId, quantity } = JSON.parse(req.body);

  // Connect to our Temporal Server running locally in Docker
  const client = new WorkflowClient();

  // Execute the order Workflow and wait for it to finish
  const result = await client.execute(order, {
    taskQueue: "my-nextjs-project",
    workflowId: "my-business-id",
    args: [userId, itemId, quantity],
  });

  return res.status(200).json({ result });
}