plotly/plotly.js · error · Error

Invalid module was attempted to be registered!

Error message

Invalid module was attempted to be registered!

What it means

Per-item guard inside Plotly.register's loop over the modules array. After the argument is normalized to an array, each entry must be a truthy, well-formed module object (with a valid moduleType and matching fields). The throw fires when a falsy entry — usually an undefined slot from a failed import or a sparse array — is encountered, so a broken module is registered instead of silently ignored.

Source

Thrown at src/registry.js:72

 *  A valid `moduleType: 'apiMethod'` module has fields:
 *  - name {string} : the api method name.
 *  - fn {function} : the api method called with Register.call();
 *
 */
exports.register = function register(_modules) {
    exports.collectableSubplotTypes = null;

    if(!_modules) {
        throw new Error('No argument passed to Plotly.register.');
    } else if(_modules && !Array.isArray(_modules)) {
        _modules = [_modules];
    }

    for(var i = 0; i < _modules.length; i++) {
        var newModule = _modules[i];

        if(!newModule) {
            throw new Error('Invalid module was attempted to be registered!');
        }

        switch(newModule.moduleType) {
            case 'trace':
                registerTraceModule(newModule);
                break;
            case 'component':
                registerComponentModule(newModule);
                break;
            case 'locale':
                registerLocale(newModule);
                break;
            case 'apiMethod':
                var name = newModule.name;
                exports.apiMethodRegistry[name] = newModule.fn;
                break;
            default:
                throw new Error('Invalid module was attempted to be registered!');

View on GitHub (pinned to 1d090e0b5f)

Solutions

1. Check each entry passed to Plotly.register is a module object imported successfully.
2. Log the array contents before registering to find the undefined element.
3. Verify the module file path/name in the partial bundle import (e.g. plotly.js/lib/scatter) is correct.
4. Filter out empty entries before calling register.

When it happens

Trigger: Thrown at src/registry.js:72 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of plotly/plotly.js@1d090e0b5f (2026-09-02). Data as JSON: /api/errors/ec5db2eeba2da667. Report an issue: GitHub.