GoogleContainerTools/jib · error · MojoExecutionException

<container><filesModificationTime> should be an ISO 8601 dat

Error message

<container><filesModificationTime> should be an ISO 8601 date-time (see DateTimeFormatter.ISO_DATE_TIME) or special keyword "EPOCH_PLUS_SECOND": <invalidFilesModificationTime>

What it means

Thrown as a MojoExecutionException from BuildTarMojo.execute when the <container><filesModificationTime> configuration value (or its jib.container.filesModificationTime property) is neither a valid ISO 8601 date-time parseable by DateTimeFormatter.ISO_DATE_TIME nor the special keyword EPOCH_PLUS_SECOND. Jib validates this value when building the container's file timestamps and fails fast with the invalid value included in the message.

Source

Thrown at jib-maven-plugin/src/main/java/com/google/cloud/tools/jib/maven/BuildTarMojo.java:123

    } catch (InvalidWorkingDirectoryException ex) {
      throw new MojoExecutionException(
          "<container><workingDirectory> is not an absolute Unix-style path: "
              + ex.getInvalidPathValue(),
          ex);
    } catch (InvalidPlatformException ex) {
      throw new MojoExecutionException(
          "<from><platforms> contains a platform configuration that is missing required values or has invalid values: "
              + ex.getMessage()
              + ": "
              + ex.getInvalidPlatform(),
          ex);
    } catch (InvalidContainerVolumeException ex) {
      throw new MojoExecutionException(
          "<container><volumes> is not an absolute Unix-style path: " + ex.getInvalidVolume(), ex);

    } catch (InvalidFilesModificationTimeException ex) {
      throw new MojoExecutionException(
          "<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 MojoExecutionException(
          "<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 MojoExecutionException(
          "error running extension '" + extensionName + "': " + ex.getMessage(), ex);

View on GitHub (pinned to fb949e2676)

Solutions

Change <filesModificationTime> to an ISO 8601 date-time such as 2021-07-28T10:15:30Z or 2021-07-28T10:15:30+02:00.
If reproducible epoch timestamps are wanted, use the literal keyword EPOCH_PLUS_SECOND exactly (no quotes/extra spaces in the XML value).
If overriding via a Maven property (-Djib.container.filesModificationTime=...), check the value for typos, surrounding whitespace, or shell-added quotes.
If the value is generated dynamically (e.g. ${maven.build.timestamp}), ensure the timestamp format property is ISO 8601, e.g. -Dmaven.build.timestamp.format=yyyy-MM-dd'T'HH:mm:ss'Z'.

Example fix

<!-- before -->
<filesModificationTime>07/28/2021 10:15</filesModificationTime>
<!-- after -->
<filesModificationTime>2021-07-28T10:15:30Z</filesModificationTime>

Defensive patterns

Strategy: validation

Validate before calling

// before running mvn, verify the configured value
String t = System.getProperty("jib.container.filesModificationTime", pomValue);
if (t != null && !t.equals("EPOCH_PLUS_SECOND")) {
  java.time.format.DateTimeFormatter.ISO_DATE_TIME.parse(t); // throws if invalid
}

Prevention

Always use ISO 8601 (yyyy-MM-dd'T'HH:mm:ss[.SSS]Z) for filesModificationTime.
Use EPOCH_PLUS_SECOND keyword for reproducible builds instead of hand-written dates.
If injecting via ${maven.build.timestamp}, set maven.build.timestamp.format=yyyy-MM-dd'T'HH:mm:ss'Z'.
Avoid shell/CI quoting that adds whitespace or quotes around the value.

When it happens

Trigger: Running `mvn jib:buildTar` (or any goal sharing this mojo error handling) with <filesModificationTime> set to a string like '2021/07/28', 'yesterday', '2021-13-45T00:00:00Z', or a typo'd keyword such as 'EPOCH_PLUS_SECOND ' with trailing whitespace/typo variants like 'EPOCH_PLUS_SEC'.

Common situations: Developers copy a human-readable date format from other tools, use a locale-dependent format, or try relative-time expressions that Jib does not support; also common when property overrides via -Djib.container.filesModificationTime carry stray whitespace or quotes.

Related errors

AI-assisted analysis of GoogleContainerTools/jib@fb949e2676 (2026-09-06). Data as JSON: /api/errors/c444d39e6499675f. Report an issue: GitHub.