pentaho/pentaho-kettle · error · RuntimeException

An error was detected in the step attributes' definition…

Error message

An error was detected in the step attributes' definition: the parent was not found for attribute {0}

What it means

Thrown by BaseStepMeta.getStepInjectionMetadataEntries when building the step injection metadata tree. Each KettleAttribute may declare a parent attribute key; if the parent's entry cannot be found among the entries already built, the attribute hierarchy is inconsistent. This is a bug in the step metadata definition, not a user configuration error.

Solutions

Check the custom step's attribute definitions and ensure every parentId/key references an attribute that exists in the list before the child.
Fix typos in the parent key string or remove the stale parentId from the child attribute.
Ensure the parent attribute is registered/added before its children so findParentEntry can locate it.
If loading from a JSON step attributes file, verify the file contains the parent attribute definition.

Example fix

// before
new KettleAttribute("rows_limit", "ROWS_LIMIT", null, "Row limit", "", ValueMetaInterface.TYPE_INTEGER, findParent(attributes, "row_lmit"));
// after
new KettleAttribute("rows_limit", "ROWS_LIMIT", null, "Row limit", "", ValueMetaInterface.TYPE_INTEGER, findParent(attributes, "row_limit"));

Defensive patterns

Strategy: validation

Validate before calling

// Validate attribute hierarchy before building injection entries
for (KettleAttribute attr : attributes) {
  if (attr.getParent() != null) {
    boolean found = attributes.stream().anyMatch(a -> a.getKey().equals(attr.getParent().getKey()));
    if (!found) throw new IllegalStateException("Missing parent for attribute " + attr.getKey());
  }
}

Try / catch

try { entries = meta.getStepInjectionMetadataEntries(); } catch (RuntimeException e) { if (e.getMessage().contains("parent was not found")) { log.error("Broken attribute hierarchy in step meta: " + e.getMessage()); } else { throw e; } }

Prevention

Always register the parent attribute before its children
Extract parent key strings into constants to avoid typos
Add a unit test that builds injection metadata entries for every custom step meta

When it happens

Trigger: Calling getStepInjectionMetadataEntries() on a step meta whose KettleAttribute list references a parent key that is not present in the attributes list, or whose parent entry appears after the child in iteration order so findParentEntry() misses it.

Common situations: Custom step plugin developers define a KettleAttribute with a parentId that was never registered (typo in the key, parent attribute removed during refactoring, or attributes loaded from an incomplete STEP_ATTRIBUTES_FILE).

Understand the failure class

Background: "Not found" and "does not exist" errors: why "Task not found", "No such folder", and "Can't find" fire when a lookup comes back empty — this error's family across 14 libraries.

Related errors

AI-assisted analysis of pentaho/pentaho-kettle@f3058517a1 (2026-09-13). Data as JSON: /api/errors/2862d5342fc4d11d. Report an issue: GitHub.

Appendix: source

Thrown at engine/src/main/java/org/pentaho/di/trans/step/BaseStepMeta.java:927

  protected StepInjectionMetaEntry createEntry( KettleAttributeInterface attr, Class<?> PKG ) {
    return new StepInjectionMetaEntry( attr.getKey(), attr.getType(), BaseMessages.getString( PKG, attr
      .getDescription() ) );
  }

  /**
   * Describe the metadata attributes that can be injected into this step metadata object.
   */
  public List<StepInjectionMetaEntry> getStepInjectionMetadataEntries( Class<?> PKG ) {
    List<StepInjectionMetaEntry> entries = new ArrayList<StepInjectionMetaEntry>();

    for ( KettleAttributeInterface attr : attributes ) {
      if ( attr.getParent() == null ) {
        entries.add( createEntry( attr, PKG ) );
      } else {
        StepInjectionMetaEntry entry = createEntry( attr, PKG );
        StepInjectionMetaEntry parentEntry = findParentEntry( entries, attr.getParent().getKey() );
        if ( parentEntry == null ) {
          throw new RuntimeException(
            "An error was detected in the step attributes' definition: the parent was not found for attribute "
              + attr );
        }
        parentEntry.getDetails().add( entry );
      }
    }

    return entries;
  }

  /**
   * Load step attributes.
   *
   * @throws KettleException the kettle exception
   */
  protected void loadStepAttributes() throws KettleException {
    try ( InputStream inputStream = getClass().getResourceAsStream( STEP_ATTRIBUTES_FILE ) ) {
      if ( inputStream != null ) {

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