flowable/flowable-engine · error · FlowableIllegalArgumentException

modelId is null

Error message

modelId is null

What it means

Identical guard to GetModelEditorSourceCmd but for the extra editor source: GetModelEditorSourceExtraCmd.execute throws FlowableIllegalArgumentException('modelId is null') when invoked without a model id. The command retrieves the auxiliary source bytes (e.g. extra JSON) attached to a model, which requires a valid id. Fail-fast validation before any entity lookup.

Solutions

1. Null-check the id before the call and raise a domain-specific error
2. Verify the model exists via repositoryService.createModelQuery() before fetching extra source
3. Validate incoming REST/model parameters before invoking the repository API
4. Debug the upstream code path that produced a null id (usually a null singleResult)

Example fix

// before
byte[] extra = repositoryService.getModelEditorSourceExtra(modelId);
// after
if (modelId == null) {
    throw new IllegalArgumentException("modelId required to fetch editor source extra");
}
byte[] extra = repositoryService.getModelEditorSourceExtra(modelId);

if (modelId == null || modelId.trim().isEmpty()) {
  throw new IllegalArgumentException("modelId must be provided before fetching extra source");
}

boolean validModelId(String id) { return id != null && !id.trim().isEmpty(); }

try {
  byte[] extra = repositoryService.getModelEditorSourceExtra(modelId);
} catch (FlowableIllegalArgumentException e) {
  throw new IllegalArgumentException("model id required", e);
}

When it happens

Trigger: Calling RepositoryService.getModelEditorSourceExtra(null); commonly the id was never set because an earlier model query returned null or the caller passed a variable that was never initialized.

Common situations: REST endpoints where the modelId path variable is missing/empty; unit tests constructing the command directly with a null constructor arg; code moved from one model object to another losing the id in between.

Related errors

• modelId is null
• appsDefinitionIds is null
• at least one of userId or groups must be provided
• Business status is null
• Candidate user is null

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/2b80baf1710d1da5. Report an issue: GitHub.

Appendix: source

Thrown at modules/flowable-engine/src/main/java/org/flowable/engine/impl/cmd/GetModelEditorSourceExtraCmd.java:37

import org.flowable.common.engine.impl.interceptor.CommandContext;
import org.flowable.engine.impl.util.CommandContextUtil;

/**
 * @author Tijs Rademakers
 */
public class GetModelEditorSourceExtraCmd implements Command<byte[]>, Serializable {

    private static final long serialVersionUID = 1L;
    protected String modelId;

    public GetModelEditorSourceExtraCmd(String modelId) {
        this.modelId = modelId;
    }

    @Override
    public byte[] execute(CommandContext commandContext) {
        if (modelId == null) {
            throw new FlowableIllegalArgumentException("modelId is null");
        }

        byte[] bytes = CommandContextUtil.getModelEntityManager(commandContext).findEditorSourceExtraByModelId(modelId);

        return bytes;
    }

}

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