3.js

// backend/server.js:15
const streamClient = new StreamChat(
  process.env.STREAM_API_KEY,
  process.env.STREAM_API_SECRET
);

// ...

// backend/server.js:57
app.post("/stream-chat-credentials", async (req, res) => {
  const { username } = req.body;
  try {
    let user = { id: username, name: username, role: 'user' };

    await streamClient.upsertUsers([user]);
    const channel = streamClient.channel('messaging', username, {
      name: 'Sales Chat',
      created_by_id: 'sales-admin'
    });

    await channel.create();
    await channel.addMembers([username]);

    const token = streamClient.createToken(user.id);

    res.send({
      userId: user.id,
      userName: user.name,
      channelId: channel.id,
      token,
      apiKey: process.env.STREAM_API_KEY
    });
  } catch (err) {
    console.log(err);
  }
});