Async registerType callback?

TotallyInformation · 15 May 2025 15:07

I might be a bit thick today but I don't seem to be able to find any magic to allow the RED.nodes.registerType callback function to be an async function?

I have a function call in it that I would ideally like to await and that has to be async.

The only other approach is a major re-write to push all of the follow-up processing into a promise .then() which is fairly horrible and hard to follow.

Anyone have any other ideas?

TotallyInformation · 15 May 2025 15:14

Sheesh! And isn't that typical. Immediately after I posted this, I worked it out!

You simply add an IIFE wrapper.

// ...
(async () => {
    try {
        await someAsyncPromisesFn()
    } catch (e) {
        log.error('It failed you numpty!`, e)
    }
})()
// ...

I've been trying to work that out for ages!

Of course, the outer function keeps going and doesn't wait - but in this case, that is fine as everything will be complete before the instance setup completes.

marcus-j-davies · 15 May 2025 15:17

You numpty!!

TotallyInformation · 15 May 2025 15:18

Yup, that's how I feel right now!

TotallyInformation · 15 May 2025 15:25

I'm trying to dig myself out of a different hole I created when I set up uibuilder's templating system.

I allowed for external templates but I didn't allow for a "standard" template to be external, only internal. Over time that has come back to haunt me as some of the templates are examples of using front-end frameworks.

As we know, FE frameworks drift over time and now, trying to maintain them within the uibuilder module has become increasingly burdensome. So I want to dump them out but I still want to have a list people can refer to.

That means firstly - simplifying the template setup. Then adapting the setup function. It has to be async because the external part relies on degit which is purely async.

Once I can do this, I can easily update the more complex templates and have even more readily available showing more complex examples and including more integrated build tools and the like.

AllanOricil · 15 May 2025 19:38

Can you share your solution? I did not see any registerType with a callback yet

Client registration:

github.com/AllanOricil/node-red-vue-inputs-experiments

src%2Findex.client.ts

main

// NOTE: this module is optional and it is generated by nrg when client.build.entryPoint isn't provided. Use this if you need to control the order nodes are registered in the editor.
import remoteServer from "./nodes/remote-server/client";
import yourNode from "./nodes/your-node/client";
import { registerType } from "./core/client";

// TODO: is there a use case for controlling the order nodes in the editor are registered?
export default async function () {
  try {
    await Promise.all([
      registerType("remote-server", remoteServer),
      registerType("your-node", yourNode),
    ]);
    console.log("All node types registered in parallel");
  } catch (error) {
    console.error("Error registering node types:", error);
  }
}

Server registration:

github.com/AllanOricil/node-red-vue-inputs-experiments

src%2Findex.server.ts

main

// NOTE: this module is optional and it is generated by nrg when server.build.entryPoint isn't provided. Use this if you need to control the order nodes are registered in the server.
import YourNode from "./nodes/your-node/server";
import RemoteServerConfigNode from "./nodes/remote-server/server";
import { registerType } from "./core/server";

// NOTE: this root module can be used to manually control the order nodes are registered
// TODO: define RED type
export default async function (RED: any) {
  try {
    // TODO: the order nodes are registered will be defined in nrg.config.ts. If not provided, it will be registered alphabetically based on the folder names
    // TODO: investigate if it is possible to run Khan's algorithm to determine the registration order
    await registerType(RED, "remote-server", RemoteServerConfigNode);
    await registerType(RED, "your-node", YourNode);

    // TODO: add the order in the message
    console.log("All node types registered in series");
  } catch (error) {
    console.error("Error registering node types:", error);
  }
}

TotallyInformation · 15 May 2025 19:51

github.com/TotallyInformation/node-red-contrib-uibuilder

nodes/uibuilder/uibuilder.js

main


      
              })
          } // ==== End of Uib ==== //
          
          /** 1a) All of the initialisation of the Node
           * This is only run once no matter how many uib node instances are added to a flow
           */
          function runtimeSetup() {
              if ( uib.RED === null ) return
              const RED = uib.RED
          
              // Check that the Node-RED userDir folder is writable - completely error if not
              try {
                  fslib.accessSync( RED.settings.userDir, 'rw' ) // try to access read/write
                  RED.log.trace(`🌐[uibuilder:runtimeSetup] uibRoot folder is read/write accessible. ${RED.settings.userDir}`)
              } catch (e) {
                  throw new Error(`🌐🛑[uibuilder:runtimeSetup] UIBUILDER cannot be configured,\n  Node-RED userDir folder "${RED.settings.userDir}" is not writable.`, e)
              }
          
              // Add list all uibuilder apps function to RED.util so it can be used inside function nodes
              // NOTE: Only add things here that require uibuilder configuration data or libraries which won't be available
              //       until after plugins are defined. Most things should be added in the the runtime plugin.

All of my nodes follow the same format. The 2nd parameter of RED.nodes.registerType references a function and it is that function that I wanted to make async. But if I try, the node won't load. It is that function that is run when an instance of your node is deployed in a flow.

I've worked around the issue by using an IIFE wrapped around an async section because I didn't actually need the whole fn to be async in the end.

AllanOricil · 15 May 2025 20:16

What is the goal with this pattern? You want to have the construction of all instances of the same node type running in series?

TotallyInformation · 15 May 2025 20:21

Sorry, not sure what you mean?

Every instance of a node MUST have its own settings and processing separate from every other node. Behind that independent instance process you have a common set of data and processes.

If you don't have an equivalent of what I call nodeInstance but many nodes have as an embedded function (which really isn't good practice), you can never have more than one set of settings shared between all instances of a node type.

In my nodes, I flatten the functional structure to make it easier to follow and to reduce the need for implied data inheritence.

My testbed node module is probably easiest to follow:

system · 14 July 2025 20:22

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Async registerType callback?

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