elastic/elasticsearch · error · InvalidUserDataException

No signatures were added to task; use properties 'signatures

Error message

No signatures were added to task; use properties 'signatures', 'bundledSignatures', 'signaturesURLs', and/or 'signaturesFiles' to define those!

What it means

Thrown after signature parsing when checker.hasNoSignatures() is true AND checker.noSignaturesFilesParsed() — meaning the task was configured with no signature sources at all (no 'signatures', 'bundledSignatures', 'signaturesURLs', or 'signaturesFiles'). The task refuses to run because a forbidden-apis check with zero rules would silently pass on everything, hiding violations.

Source

Thrown at build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/precommit/CheckForbiddenApisTask.java:524

                        checker.parseSignaturesFile(f);
                    }
                    final List<String> signatures = getParameters().getSignatures().get();
                    if ((signatures != null) && !signatures.isEmpty()) {
                        final StringBuilder sb = new StringBuilder();
                        for (String line : signatures) {
                            sb.append(line).append(NL);
                        }
                        checker.parseSignaturesString(sb.toString());
                    }
                } catch (IOException ioe) {
                    throw new GradleException("IO problem while reading files with API signatures.", ioe);
                } catch (ParseException pe) {
                    throw new InvalidUserDataException("Parsing signatures failed: " + pe.getMessage(), pe);
                }

                if (checker.hasNoSignatures()) {
                    if (checker.noSignaturesFilesParsed()) {
                        throw new InvalidUserDataException(
                            "No signatures were added to task; use properties 'signatures', 'bundledSignatures', 'signaturesURLs', and/or 'signaturesFiles' to define those!"
                        );
                    } else {
                        logger.info("Skipping execution because no API signatures are available.");
                        return;
                    }
                }

                try {
                    checker.addClassesToCheck(getParameters().getClassFiles());
                } catch (IOException ioe) {
                    throw new GradleException("Failed to load one of the given class files.", ioe);
                }
                checker.run();
                writeMarker(getParameters().getSuccessMarker().getAsFile().get());
            } catch (ForbiddenApiException e) {
                throw new VerificationException("Forbidden API verification failed", e);
            } catch (Exception e) {

View on GitHub (pinned to db6a809a66)

Solutions

1. Add at least one signature source, most commonly bundledSignatures: task.bundledSignatures = ['jdk-system-out', 'jdk-unsafe'].
2. Or add signaturesFiles / signatures / signaturesURLs as appropriate.
3. If the task is intentionally a no-op, remove the task registration rather than leaving an empty one.

Example fix

// before
tasks.named('forbiddenApisMain', CheckForbiddenApisTask) {
  // no signatures
}

// after
tasks.named('forbiddenApisMain', CheckForbiddenApisTask) {
  bundledSignatures = ['jdk-system-out', 'jdk-unsafe', 'jdk-deprecated']
}

// Assert at configuration time that at least one signature source is set
boolean hasAny = (bundledSignatures != null && !bundledSignatures.isEmpty())
             || (signatures != null && !signatures.isEmpty())
             || (signaturesFiles != null && !signaturesFiles.isEmpty())
             || (signaturesURLs != null && !signaturesURLs.isEmpty());
if (!hasAny) throw new InvalidUserDataException("forbidden-apis task needs at least one signature source");

When it happens

Trigger: A CheckForbiddenApisTask registration where none of the four signature-supplying properties were set, or all were set to empty.

Common situations: Registering a forbidden-apis task as a placeholder and forgetting to add bundledSignatures; a refactor that removed the signatures block; copying a task config and dropping the bundledSignatures line.

Related errors

• IO problem while reading files with API signatures.
• Parsing signatures failed: {}
• Missing 'classesDirs' or 'classpath' property.
• Failed to load one of the given class files.
• Forbidden API verification failed

AI-assisted analysis of elastic/elasticsearch@db6a809a66 (2026-08-12). Data as JSON: /api/errors/73b81b68995b2dfa. Report an issue: GitHub.