GoogleContainerTools/jib · error · GradleException

error running extension '${extensionName}': ${ex.getMessage(

Error message

error running extension '${extensionName}': ${ex.getMessage()}

What it means

When a Jib plugin extension (JibPluginExtensionException) fails during jibBuildTar, BuildTarTask.buildTar rethrows it as a GradleException with the extension class' fully-qualified name and the extension's own message. This means a Jib extension (e.g. jib-spring-boot or a custom build-plan modifier) threw while computing or applying its container build plan.

Source

Thrown at jib-gradle-plugin/src/main/java/com/google/cloud/tools/jib/gradle/BuildTarTask.java:188

    } catch (InvalidFilesModificationTimeException ex) {
      throw new GradleException(
          "container.filesModificationTime should be an ISO 8601 date-time (see "
              + "DateTimeFormatter.ISO_DATE_TIME) or special keyword \"EPOCH_PLUS_SECOND\": "
              + ex.getInvalidFilesModificationTime(),
          ex);

    } catch (InvalidCreationTimeException ex) {
      throw new GradleException(
          "container.creationTime should be an ISO 8601 date-time (see "
              + "DateTimeFormatter.ISO_DATE_TIME) or a special keyword (\"EPOCH\", "
              + "\"USE_CURRENT_TIMESTAMP\"): "
              + ex.getInvalidCreationTime(),
          ex);

    } catch (JibPluginExtensionException ex) {
      String extensionName = ex.getExtensionClass().getName();
      throw new GradleException(
          "error running extension '" + extensionName + "': " + ex.getMessage(), ex);

    } catch (IncompatibleBaseImageJavaVersionException ex) {
      throw new GradleException(
          HelpfulSuggestions.forIncompatibleBaseImageJavaVersionForGradle(
              ex.getBaseImageMajorJavaVersion(), ex.getProjectMajorJavaVersion()),
          ex);

    } catch (InvalidImageReferenceException ex) {
      throw new GradleException(
          HelpfulSuggestions.forInvalidImageReference(ex.getInvalidReference()), ex);

    } catch (ExtraDirectoryNotFoundException ex) {
      throw new GradleException(
          "extraDirectories.paths contain \"from\" directory that doesn't exist locally: "
              + ex.getPath(),
          ex);
    } finally {

View on GitHub (pinned to fb949e2676)

Solutions

1. Read the wrapped extension message in the cause ('Caused by') and fix the project/config issue it describes
2. Remove or disable the pluginExtension configuration if it is not needed (e.g. jib-spring-boot on a non-Boot project)
3. Check the extension's documentation for prerequisites (required tasks, artifacts, Jib API version) and update the extension/Jib to compatible versions

Example fix

// before (non-Boot project with spring-boot extension configured)
jib { pluginExtensions { pluginExtension { implementation = 'com.google.cloud.tools.jib.gradle.extension.springboot.JibSpringBootExtension' } } }
// after: remove the pluginExtension block, or make the project a Spring Boot application so bootJar exists

// Ensure prerequisites exist before running jib with extensions
tasks.named('jibBuildTar') { dependsOn tasks.named('jar') }

try {
  tasks.named('jibBuildTar')
} catch (GradleException e) {
  if (e.message.startsWith('error running extension')) {
    logger.error('Extension failed: ' + e.cause?.message)
    // fall back to a build without the extension or rethrow with context
  } else throw e
}

When it happens

Trigger: Running a jib task with a pluginExtension configured whose extend() implementation (or a Jib-provided extension) throws a JibPluginExtensionException; the exception message is propagated verbatim into 'error running extension <FQCN>: <message>'.

Common situations: Using jib-spring-boot against a project that is not a Spring Boot app (no bootJar artifacts); a third-party extension with a bug or incompatible Jib version; extension fails because the project layout does not match its assumptions.

Related errors

• invalid base image reference: ${buildPlan.getBaseImage()}
• extension ${extension.getClass().getSimpleName()} does not e
• extension crashed: ${ex.getMessage()}
• container.appRoot is not an absolute Unix-style path: ${inva
• invalid value for containerizingMode: ${invalidContainerizin

AI-assisted analysis of GoogleContainerTools/jib@fb949e2676 (2026-09-06). Data as JSON: /api/errors/a400efe48bd3d33c. Report an issue: GitHub.