openapi-generator "Can't load config class ... unsupported generator name" in CI

By Daniel Zoghalchali·Latchkey

The -g flag selects a generator by name (for example typescript-axios, go, spring). When the name is misspelled or not present in the installed version, OpenAPI Generator fails with "Can't load config class with name ..." and lists what it could not find.

What this error means

openapi-generator-cli fails with "Can't load config class with name <name>. Available options: ..." and exits before generating.

Exception in thread "main" java.lang.RuntimeException:
Can't load config class with name ".//typescript-axious"
Available options:
aspnetcore
...

Common causes

The generator name is misspelled

A typo like typescript-axious does not match any registered generator, so the loader cannot find a config class.

The generator is not in the installed version

The name belongs to a newer (or a plugin) generator not bundled in the version of openapi-generator pinned in CI.

How to fix it

List generators and use the exact name

1. Run openapi-generator-cli list to see available names.
2. Replace -g with the exact, correctly spelled generator name.
3. Re-run generation.

openapi-generator-cli list
openapi-generator-cli generate -i openapi.yaml -g typescript-axios -o ./client

Pin a version that includes the generator

If the generator is newer, pin the CLI to a version that ships it so the name resolves.

# openapitools.json
{
  "generator-cli": { "version": "7.5.0" }
}

How to prevent it

• Use openapi-generator-cli list to confirm generator names.
• Pin the generator CLI version in openapitools.json.
• Keep the generator name in one place (a script) to avoid typos.

Frequently asked questions

Related guides

References

• GitHub Actions documentation