# Improvement to debugging early errors when loading nodes
**URL:** https://discourse.nodered.org/t/improvement-to-debugging-early-errors-when-loading-nodes/98197
**Category:** Feature Requests
**Created:** [18 July 2025 09:31 UTC](https://discourse.nodered.org/t/improvement-to-debugging-early-errors-when-loading-nodes/98197 "2025-07-18T09:31:12Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)
#### Post date: [18 July 2025 09:31 UTC](https://discourse.nodered.org/t/improvement-to-debugging-early-errors-when-loading-nodes/98197/1 "2025-07-18T09:31:12Z")
Hi, I managed to break something when messing around and I was reminded of an annoying oversight in `loader.js`.
Around lines 78 to 98, there are a couple of try/catch sections but the catch does not really show anything useful.
Here is an example from my recent log:
```auto
Welcome to Node-RED
===================
0|Node-RED |
18 Jul 10:19:34 - [info] Node-RED version: v4.1.0-beta.2
18 Jul 10:19:34 - [info] Node.js version: v22.15.0
18 Jul 10:19:34 - [info] Windows_NT 10.0.26100 x64 LE
18 Jul 10:19:35 - [info] Loading palette nodes
TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received undefined
at Object.dirname (node:path:739:5)
at loadNodeLocales (D:\src\nr\node_modules\@node-red\registry\lib\loader.js:234:35)
at loadPluginConfig (D:\src\nr\node_modules\@node-red\registry\lib\loader.js:331:11)
at loadModuleTypeFiles (D:\src\nr\node_modules\@node-red\registry\lib\loader.js:83:31)
at loadModuleFiles (D:\src\nr\node_modules\@node-red\registry\lib\loader.js:122:60)
at load (D:\src\nr\node_modules\@node-red\registry\lib\loader.js:43:12)
at process.processTicksAndRejections (node:internal/process/task_queues:105:5) {
code: 'ERR_INVALID_ARG_TYPE'
}
18 Jul 10:19:35 - [info] Node-RED Contrib Theme Collection version: v4.0.11
```
As you can see, this does not tell me which node/plugin failed to load.
Thankfully, there is a very easy fix for this:
```js
try {
let promise;
if (type === "nodes") {
promise = loadNodeConfig(things[thingName]);
} else if (type === "plugins") {
promise = loadPluginConfig(things[thingName]);
}
promises.push(
promise.then(
(function() {
const n = thingName;
return function(nodeSet) {
things[n] = nodeSet;
return nodeSet;
}
})()
).catch(err => {console.log(`"${thingName}"`, err)})
);
} catch(err) {
console.log(`"${thingName}"`, err)
}
}
```
Notice the addition of `thingName` to the log output. Which means that we now get to see what node/plugin caused the issue:
```auto
Welcome to Node-RED
===================
0|Node-RED |
18 Jul 10:29:20 - [info] Node-RED version: v4.1.0-beta.2
18 Jul 10:29:20 - [info] Node.js version: v22.15.0
18 Jul 10:29:20 - [info] Windows_NT 10.0.26100 x64 LE
18 Jul 10:29:21 - [info] Loading palette nodes
"ti-dummy-runtime-plugin" TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received undefined
at Object.dirname (node:path:739:5)
at loadNodeLocales (D:\src\nr\node_modules\@node-red\registry\lib\loader.js:234:35)
at loadPluginConfig (D:\src\nr\node_modules\@node-red\registry\lib\loader.js:331:11)
at loadModuleTypeFiles (D:\src\nr\node_modules\@node-red\registry\lib\loader.js:83:31)
at loadModuleFiles (D:\src\nr\node_modules\@node-red\registry\lib\loader.js:122:60)
at load (D:\src\nr\node_modules\@node-red\registry\lib\loader.js:43:12)
at process.processTicksAndRejections (node:internal/process/task_queues:105:5) {
code: 'ERR_INVALID_ARG_TYPE'
}
18 Jul 10:29:22 - [info] Node-RED Contrib Theme Collection version: v4.0.11
```
A nice easy fix. 😃
---
### Author:  [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)
#### Post date: [18 July 2025 10:28 UTC](https://discourse.nodered.org/t/improvement-to-debugging-early-errors-when-loading-nodes/98197/2 "2025-07-18T10:28:00Z")
While debugging all this, I've also found some small bugs in `loader.js`.
I've tested both of the proposed fixes.
## `loadPluginConfig`
This function tries to set both `plugin.file` and `plugin.template`. At least one of these is needed for the call to `loadNodeLocales(plugin)`. This can fail if the plugin js is in a file `*.cjs` rather than `*.js` even though `*.cjs` is a perfectly valid filename.
At the least, I believe `loadPluginConfig` should throw a meaningful error if neither `file` nor `template` properties exist.
Ideally, the `*.js` file check should be expanded to look for `*.cjs` if the first check fails. Possibly also look for `*.mjs` if needed to allow for future use of modules.
Example fix:
```js
var jsFile = file.replace(/\.[^.]+$/,".js");
var htmlFile = file.replace(/\.[^.]+$/,".html");
if (fs.existsSync(jsFile)) {
plugin.file = jsFile;
} else {
jsFile = file.replace(/\.[^.]+$/,".cjs")
if (fs.existsSync(jsFile)) {
plugin.file = jsFile;
}
}
if (fs.existsSync(htmlFile)) {
plugin.template = htmlFile;
}
if (!plugin.file && !plugin.template) {
throw new Error(`Plugin file not found: "${file}"`);
}
await loadNodeLocales(plugin)
```
## `loadNodeConfig`
This is a little simpler but fails for a similar but not quite identical issue. In this case, the `file` property is OK but the `template` property fails because, again, the `replace` assumes a source filename in the pattern `*.js`. This is actually an easier fix because we can easily extend the regex.
Old regex: `/\.js$/i`
New regex: `/\.(js|cjs)$/i`
---
### Author:  [@knolleary](https://discourse.nodered.org/u/knolleary)
#### Post date: [18 July 2025 10:44 UTC](https://discourse.nodered.org/t/improvement-to-debugging-early-errors-when-loading-nodes/98197/3 "2025-07-18T10:44:47Z")
Please raise on github - either as an issue, or even a PR given you have proposed specific code changes. The forum isn't the place to report bugs.
---
### Author:  [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)
#### Post date: [18 July 2025 10:47 UTC](https://discourse.nodered.org/t/improvement-to-debugging-early-errors-when-loading-nodes/98197/4 "2025-07-18T10:47:20Z")
I wasn't sure it was a bug - the initial part is an enhancement request rather than a bug report.
However, I will report the bug.
Done:
>
>
> \### Current Behavior
>
> Reference: https://discourse.nodered.org/t/improvement-to-…debugging-early-errors-when-loading-nodes/98197
>
> I've found some small bugs in loader.js.
>
> I've tested both of the proposed fixes.
>
> \## loadPluginConfig
>
> This function tries to set both \`plugin.file\` and \`plugin.template\`. At least one of these is needed for the call to loadNodeLocales(plugin). This can fail if the plugin js is in a file \`\*.cjs\` rather than \`\*.js\` even though \`\*.cjs\` is a perfectly valid filename.
>
> At the least, I believe \`loadPluginConfig\` should throw a meaningful error if neither file nor template properties exist.
>
> Ideally, the \`\*.js\` file check should be expanded to look for \`\*.cjs\` if the first check fails. Possibly also look for \`\*.mjs\` if needed to allow for future use of modules.
>
> Example fix:
>
> \`\`\`js
> var jsFile = file.replace(/\\.\[^.\]+$/,".js");
> var htmlFile = file.replace(/\\.\[^.\]+$/,".html");
> if (fs.existsSync(jsFile)) {
> plugin.file = jsFile;
> } else {
> jsFile = file.replace(/\\.\[^.\]+$/,".cjs")
> if (fs.existsSync(jsFile)) {
> plugin.file = jsFile;
> }
> }
> if (fs.existsSync(htmlFile)) {
> plugin.template = htmlFile;
> }
> if (!plugin.file && !plugin.template) {
> throw new Error(\`Plugin file not found: "${file}"\`);
> }
>
> await loadNodeLocales(plugin)
> \`\`\`
>
> \## loadNodeConfig
>
> This is a little simpler but fails for a similar but not quite identical issue. In this case, the file property is OK but the template property fails because, again, the replace assumes a source filename in the pattern \*.js. This is actually an easier fix because we can easily extend the regex.
>
> Old regex: \`/\\.js$/i\`
> New regex: \`/\\.(js|cjs)$/i\`
>
> \### Expected Behavior
>
> The loader should be able to load both nodes and plugins having a file name \`\*.cjs\` (and possibly also \`\*.mjs\`).
>
> \### Steps To Reproduce
>
> Attempt to load a node or runtime plugin using \`cjs\` as the file extension.
>
> \### Example flow
>
> N/A
>
>
> \### Environment
>
> \- Platform/OS: Windows 11
> \- Browser: N/A
>
> \`\`\`
> 0|Node-RED | 18 Jul 11:26:57 - \[info\] Node-RED version: v4.1.0-beta.2
> 0|Node-RED | 18 Jul 11:26:57 - \[info\] Node.js version: v22.15.0
> 0|Node-RED | 18 Jul 11:26:57 - \[info\] Windows\_NT 10.0.26100 x64 LE
> \`\`\`
---
### Author:  [@system](https://discourse.nodered.org/u/system)
#### Post date: [16 September 2025 10:48 UTC](https://discourse.nodered.org/t/improvement-to-debugging-early-errors-when-loading-nodes/98197/5 "2025-09-16T10:48:10Z")
This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.