GoogleContainerTools/jib · error · IllegalArgumentException

'${entry}' is not a valid key-value pair

Error message

'${entry}' is not a valid key-value pair

What it means

ConfigurationPropertyValidator.parseMapProperty parses plugin configuration properties given as comma-separated key=value entries (e.g. jib.container.environment). Each entry must match the KEY_VALUE_PATTERN (name=value); if an entry lacks the '=' separator or is malformed, an IllegalArgumentException is thrown telling you which entry is invalid.

Source

Thrown at jib-plugins-common/src/main/java/com/google/cloud/tools/jib/plugins/common/ConfigurationPropertyValidator.java:146

    }
  }

  /**
   * Parses a string in the form of "key1=value1,key2=value2,..." into a map.
   *
   * @param property the map string to parse, with entries separated by "," and key-value pairs
   *     separated by "="
   * @return the map of parsed values
   */
  public static Map<String, String> parseMapProperty(String property) {
    Map<String, String> result = new LinkedHashMap<>(); // LinkedHashMap to keep insertion order

    // Split on non-escaped commas
    List<String> entries = parseListProperty(property);
    for (String entry : entries) {
      Matcher matcher = KEY_VALUE_PATTERN.matcher(entry);
      if (!matcher.matches()) {
        throw new IllegalArgumentException("'" + entry + "' is not a valid key-value pair");
      }
      result.put(matcher.group("name"), matcher.group("value"));
    }
    return result;
  }

  /**
   * Parses a comma-separated string into a list. Ignores commas escaped with "\".
   *
   * @param property the comma-separated string
   * @return the list of parsed values
   */
  public static List<String> parseListProperty(String property) {
    List<String> items = new ArrayList<>();
    StringBuilder token = new StringBuilder();
    for (int i = 0; i < property.length(); i++) {
      if (property.charAt(i) == ',') {
        // Split on non-escaped comma

View on GitHub (pinned to fb949e2676)

Solutions

  1. Give every entry a `key=value` form: `-Djib.container.environment=DEBUG=1`.
  2. Escape literal commas inside values with a backslash (`key=a\,b`) or move the config to pom.xml/build.gradle where lists are structured.
  3. Remove empty entries caused by trailing/duplicate commas.
  4. Check the plugin docs for the exact property format before using the CLI flag form.

Example fix

// before
mvn jib:build -Djib.container.environment=DEBUG
// after
mvn jib:build -Djib.container.environment=DEBUG=1
Defensive patterns

Strategy: validation

Validate before calling

// validate every entry has a key=value form before invoking Jib
const entries = prop.split(/(?<!\\),/);
const bad = entries.filter(e => !/^[^=]+=/.test(e));
if (bad.length) throw new Error('Not key=value: ' + bad.join(', '));

Try / catch

try { jibBuild() } catch (IllegalArgumentException e) {
  if (e.message.contains('is not a valid key-value pair')) {
    // fix the named entry in the message: add '=value' or escape commas
  }
}

Prevention

When it happens

Trigger: Passing a map-like plugin property (e.g. `jib.container.environment=FOO` or `jib.container.labels=foo,bar=baz`) where an entry has no `name=value` form, e.g. a bare key without '=' or an empty entry from a stray comma.

Common situations: Maven command-line `-Djib.container.environment=DEBUG` (missing =VALUE); Gradle `jib.container.labels 'someLabel'`; a typo'd entry in pom.xml/build.gradle; commas inside values without escaping.

Understand the failure class

Background: "Invalid ... format", "must be in format X", "does not look like a ..." — invalid argument format errors across CLI tools and libraries — this error's family across 17 libraries.

Related errors

AI-assisted analysis of GoogleContainerTools/jib@fb949e2676 (2026-09-06). Data as JSON: /api/errors/948d2203942d7e01. Report an issue: GitHub.