Managing Multi Tenant Node-RED Instances

Over the last series of posts I’ve outlined how to build all the components that are needed for a Multi Tenant Node-RED service. What’s missing is a way to automate the spinning up of new instances.

One option would be to do this with Node-RED it’s self, you can drive docker using the node-red-contrib-dockerode, but for this I’ve decided to create a dedicated application.

I’ve written a small Express app that uses dockerode directly and also will populate the Users collection in the MongoDB with the admin password for the editor and then spin up a new instance.

docker.createContainer({
  Image: "custom-node-red",
  name: req.body.appname,
  Env: [
    "VIRTUAL_HOST=" + req.body.appname + "." + settings.rootDomain,
    "APP_NAME="+ req.body.appname,
    "MONGO_URL=mongodb://mongodb/nodered"
  ],
  AttachStdin: false,
  AttachStdout: false,
  AttachStderr: false,
  HostConfig: {
    Links: [
      "mongodb:mongodb"
    ]
  }
})
.then(container => {
  console.log("created");
  cont = container;
  return container.start()
})
.then(() => {
  res.status(201).send({started: true, url: "http://" + req.body.appname + "." + settings.rootDomain});
})

It’s pretty basic but it does just enough to get started. It is being exposed using the same nginx-proxy that exposes the Node-RED instances, so the management interface is available on the manger.docker-pi.local domain. If it was being deployed in a production environment it should probably not be internet facing and should have some basic access control to prevent anybody from being able to stand up a new Node-RED instance.

When the app has completed creating a new instance a link to that instance is displayed.

You can also Start/Stop/Remove the instance as well as streaming the logs via a websocket.

Thanks to Dave Conway-Jones (@ceejay) for help with making my very utilitarian UI look a lot better.

The code for the management app is on github here