io.confluent.license

Class LicenseManager

java.lang.Object

io.confluent.license.LicenseManager

public class LicenseManager
extends Object

A license manager that can validate and store Confluent licenses in a topic in one Kafka cluster.

This manager is supplied configurations for an admin client to create the topic if necessary, a consumer to read the contents of that topic, and a producer to store the updated license information, if such is supplied when registering and validating licenses. Additional admin client configurations can be provided for Kafka clusters that the license manager should consider when validating a license.

Types of Licenses

This license manager deal with three types of licenses:

1. Enterprise License is a license that is generated by Confluent for enterprise customers, and which expires after a specfied period of time. Customers can renew their license, and the new license should be stored in the topic, either by updating a component with that license or by directly writing it.
2. 30 Day Trial License allows users to download and evaluate Confluent products by for up to 30 days before the license expires and the components stop working.
3. Free Forever Single Node Cluster License allows users to download and evaluate Confluent products for an unlimited time as long as they run at most one broker in their Kafka clusters. This type of license only applies if there is not already another type of license stored in the topic (even if expired), and is considered valid only when the clusters have only one broker.

Usage

To use the LicenseManager, instantiate it with the correct configurations for the primary Kafka cluster where the license topic exists. If the licensed component uses more than one Kafka cluster, also supply admin client configurations for the additional cluster(s) so that the license manager can ensure that the restrictions of the Free Forever license are followed, if that license is used.

The next step is to read the license information from the component's configuration, or use a blank string if the user did not provide a license, and call registerOrValidateLicense(String) to register the new license or, if it is blank, attempt to read a previously-stored license. This method will thrown an InvalidLicenseException if the license is not valid or has expired. Otherwise, a valid license exists and is returned for use by the application.

Note that the registerOrValidateLicense(String) logs information about the license, either at WARN level if the license expires within 10 days, or at INFO level otherwise. The message includes the type of license, the number of days until the license expires, and the expiration date.

Finally, when the application stops, call stop() so the LicenseManager can release any resources it might have created.

Here is an example:

   // Read the license string from the application or component's configuration
   String licenseStr = ...

   // Start the license manager
   String topicName = ...
   Map<String, Object> producerConfig = ...
   Map<String, Object> consumerConfig = ...
   Map<String, Object> adminConfig = ...

   LicenseManager licenseMgr = new LicenseManager(
       producerConfig,
       consumerConfig,
       adminConfig);
   License license = licenseMgr.registerOrValidateLicense(licenseStr);

   // At some point stop the license manager
   licenseMgr.stop();
 

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	LicenseManager.BasicClusterClient
protected static interface	LicenseManager.ClusterClient
protected static class	LicenseManager.LicenseChangedEvent
static class	LicenseManager.LicenseStatus License status enumeration for license validation operations

Field Summary

Fields

Modifier and Type	Field and Description
protected static long	WARN_THRESHOLD_DAYS

Constructor Summary

Constructors

Modifier	Constructor and Description
	LicenseManager(ConfluentLicenseStore licenseStore, String configuredLicenseStr)
	LicenseManager(ConfluentLicenseStore licenseStore, String configuredLicenseStr, LicenseAutoGenerationPolicy licenseAutoGenerationPolicy)
	LicenseManager(ConfluentLicenseStore licenseStore, String configuredLicenseStr, LicenseManagerPurpose licenseManagerPurpose)
	LicenseManager(ConfluentLicenseStore licenseStore, String configuredLicenseStr, LicenseManagerPurpose licenseManagerPurpose, org.apache.kafka.common.utils.Time time)
	LicenseManager(ConfluentLicenseStore licenseStore, String configuredLicenseStr, LicenseManagerPurpose licenseManagerPurpose, org.apache.kafka.common.utils.Time time, LicenseAutoGenerationPolicy licenseAutoGenerationPolicy)
protected	LicenseManager(LicenseManager.ClusterClient primaryClusterClient, LicenseStore licenseStore, org.apache.kafka.common.utils.Time time)
protected	LicenseManager(LicenseManager.ClusterClient primaryClusterClient, LicenseStore licenseStore, org.apache.kafka.common.utils.Time time, LicenseManagerPurpose licenseManagerPurpose)
protected	LicenseManager(LicenseManager.ClusterClient primaryClusterClient, LicenseStore licenseStore, org.apache.kafka.common.utils.Time time, String configuredLicenseStr, boolean startStore, boolean allowInvalidLicenseToRun)
protected	LicenseManager(LicenseManager.ClusterClient primaryClusterClient, LicenseStore licenseStore, org.apache.kafka.common.utils.Time time, String configuredLicenseStr, boolean startStore, boolean allowInvalidLicenseToRun, LicenseManagerPurpose licenseManagerPurpose)
	LicenseManager(Map<String,Object> topicConfig, LicenseStore licenseStore, String configuredLicense, boolean startStore)
	LicenseManager(Map<String,Object> topicConfig, LicenseStore licenseStore, String configuredLicense, boolean startStore, boolean allowInvalidLicenseToRun)
	LicenseManager(String topic, Map<String,Object> producerConfig, Map<String,Object> consumerConfig, Map<String,Object> topicConfig) Create a new license manager that uses the specified topic for licenses, configurations for an admin client, producer, and consumer to create, write to, and read from that topic in a primary Kafka cluster.
	LicenseManager(String topic, Map<String,Object> producerConfig, Map<String,Object> consumerConfig, Map<String,Object> topicConfig, Duration topicCreateTimeout, Duration retryBackoffMinMs, Duration retryBackoffMaxMs)
	LicenseManager(String topic, Map<String,Object> producerConfig, Map<String,Object> consumerConfig, Map<String,Object> topicConfig, LicenseManagerPurpose licenseManagerPurpose)

Method Summary

Modifier and Type	Method and Description
void	addCluster(String key, LicenseManager.ClusterClient client) Add another Kafka cluster to be considered when validating a license.
void	addCluster(String key, Map<String,Object> adminConfig) Add another Kafka cluster to be considered when validating a license.
boolean	addListener(Consumer<LicenseChanged> listener) Add a listener for subsequent license changes.
License	configuredLicense()
protected void	doStart()
protected void	doStop()
protected License	generateLicense(long now)
protected boolean	hasOnlySingleNodeClusters()
static PublicKey	loadPublicKey()
protected void	notifyLicense(License newLicense, License oldLicense, List<License> finalInstalledLicense, String reason)
protected License	readLicense(PublicKey publicKey, String licenseStr, boolean stored)
License	registerOrValidateAddOnLicense(String license) Validate the supplied license, or if blank register a new trial license.
License	registerOrValidateLicense(String license) Validates a supplied CP or 'CP for CC' license and persists it in LicenseStore.
List<License>	registerOrValidateMultiLicense(String license, boolean skipTrialLicenseGeneration) Validates a supplied CP or 'CP for CC' license, persists it in LicenseStore.
boolean	removeCluster(String key) Remove the Kafka cluster client with the specific name from being considered when validating a license.
boolean	removeListener(Consumer<LicenseChanged> listener) Remove a previously registered license change listener.
void	setSchedulingStrategy(Function<List<License>,License> selectionFunction)
void	start() Begin running this license manager's check on a daily schedule, or more frequently if the license is expired or has less than 1 day remaining.
void	start(long initialDelay, long period, TimeUnit timeUnit) Begin running this license manager's check with a configurable initial delay and period.
void	stop() Stop this license manager, close any resources, and remove any scheduled license checks.
long	timeUntilLicenseExpirationMs()
void	timeUntilLicenseExpirationMs(long timeMs)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

WARN_THRESHOLD_DAYS

protected static final long WARN_THRESHOLD_DAYS

See Also:

Constant Field Values

Constructor Detail

LicenseManager

public LicenseManager(String topic,
                      Map<String,Object> producerConfig,
                      Map<String,Object> consumerConfig,
                      Map<String,Object> topicConfig)

Create a new license manager that uses the specified topic for licenses, configurations for an admin client, producer, and consumer to create, write to, and read from that topic in a primary Kafka cluster.

Parameters:

topic - the name of the topic where licenses are persisted; may not be null

producerConfig - the configuration for the producer used to write to the license topic; may not be null

consumerConfig - the configuration for the consumer used to read from the license topic; may not be null

topicConfig - the configuration for the admin client to create the license topic if required; may not be null

LicenseManager

public LicenseManager(String topic,
                      Map<String,Object> producerConfig,
                      Map<String,Object> consumerConfig,
                      Map<String,Object> topicConfig,
                      LicenseManagerPurpose licenseManagerPurpose)

LicenseManager

public LicenseManager(String topic,
                      Map<String,Object> producerConfig,
                      Map<String,Object> consumerConfig,
                      Map<String,Object> topicConfig,
                      Duration topicCreateTimeout,
                      Duration retryBackoffMinMs,
                      Duration retryBackoffMaxMs)

LicenseManager

public LicenseManager(Map<String,Object> topicConfig,
                      LicenseStore licenseStore,
                      String configuredLicense,
                      boolean startStore)

LicenseManager

public LicenseManager(Map<String,Object> topicConfig,
                      LicenseStore licenseStore,
                      String configuredLicense,
                      boolean startStore,
                      boolean allowInvalidLicenseToRun)

LicenseManager

protected LicenseManager(LicenseManager.ClusterClient primaryClusterClient,
                         LicenseStore licenseStore,
                         org.apache.kafka.common.utils.Time time)

LicenseManager

protected LicenseManager(LicenseManager.ClusterClient primaryClusterClient,
                         LicenseStore licenseStore,
                         org.apache.kafka.common.utils.Time time,
                         LicenseManagerPurpose licenseManagerPurpose)

LicenseManager

protected LicenseManager(LicenseManager.ClusterClient primaryClusterClient,
                         LicenseStore licenseStore,
                         org.apache.kafka.common.utils.Time time,
                         String configuredLicenseStr,
                         boolean startStore,
                         boolean allowInvalidLicenseToRun)

LicenseManager

protected LicenseManager(LicenseManager.ClusterClient primaryClusterClient,
                         LicenseStore licenseStore,
                         org.apache.kafka.common.utils.Time time,
                         String configuredLicenseStr,
                         boolean startStore,
                         boolean allowInvalidLicenseToRun,
                         LicenseManagerPurpose licenseManagerPurpose)

LicenseManager

public LicenseManager(ConfluentLicenseStore licenseStore,
                      String configuredLicenseStr)

LicenseManager

public LicenseManager(ConfluentLicenseStore licenseStore,
                      String configuredLicenseStr,
                      LicenseAutoGenerationPolicy licenseAutoGenerationPolicy)

LicenseManager

public LicenseManager(ConfluentLicenseStore licenseStore,
                      String configuredLicenseStr,
                      LicenseManagerPurpose licenseManagerPurpose)

LicenseManager

public LicenseManager(ConfluentLicenseStore licenseStore,
                      String configuredLicenseStr,
                      LicenseManagerPurpose licenseManagerPurpose,
                      org.apache.kafka.common.utils.Time time)

LicenseManager

public LicenseManager(ConfluentLicenseStore licenseStore,
                      String configuredLicenseStr,
                      LicenseManagerPurpose licenseManagerPurpose,
                      org.apache.kafka.common.utils.Time time,
                      LicenseAutoGenerationPolicy licenseAutoGenerationPolicy)

Method Detail

addCluster

public void addCluster(String key,
                       Map<String,Object> adminConfig)

Add another Kafka cluster to be considered when validating a license. The cluster is defined with the AdminClientConfig for the cluster, and the principal requires privilege to read the cluster metadata.

This method is safe to be called whether or not the license manager is running.

Parameters:

adminConfig - the admin client configurations for another Kafka clusters that should be considered during license validation; may be null or empty

addCluster

public void addCluster(String key,
                       LicenseManager.ClusterClient client)

Add another Kafka cluster to be considered when validating a license. The cluster is defined with the supplied LicenseManager.ClusterClient function, allowing callers to fully control how the license manager determines the size of a cluster.

This method is safe to be called whether or not the license manager is running.

Parameters:

key - the unique key for the cluster client; may not be null

client - the cluster client function that should be used to determine the size of a cluster during license validation; may be null or empty

removeCluster

public boolean removeCluster(String key)

Remove the Kafka cluster client with the specific name from being considered when validating a license.

This method is safe to be called whether or not the license manager is running.

Returns:

true if the admin config was removed, or false otherwise

addListener

public boolean addListener(Consumer<LicenseChanged> listener)

Add a listener for subsequent license changes.

Parameters:

listener - the function that is to be called when license changes are detected

Returns:

true if the listener was added, or false if the listener was null or was already a listener

See Also:

removeListener(Consumer)

removeListener

public boolean removeListener(Consumer<LicenseChanged> listener)

Remove a previously registered license change listener.

Parameters:

listener - the function that is no longer to be called when license changes are detected

Returns:

true if the listener was removed, or false if the listener was not previously registered

See Also:

addListener(Consumer)

start

public void start()

Begin running this license manager's check on a daily schedule, or more frequently if the license is expired or has less than 1 day remaining. The first check will be scheduled for 24 hours after this method is called, since the calling application is expected to explicitly check the license once upon startup before this method is called.

This is useful for automatically detecting changes in the license and notifying the listeners.

See Also:

addListener(Consumer), removeListener(Consumer)

setSchedulingStrategy

public void setSchedulingStrategy(Function<List<License>,License> selectionFunction)

start

public void start(long initialDelay,
                  long period,
                  TimeUnit timeUnit)

Begin running this license manager's check with a configurable initial delay and period.

Parameters:

initialDelay - the initial delay period for the first check

period - the frequency of the following checks

timeUnit - the timeunit used for the initialDelay and the period

stop

public void stop()

Stop this license manager, close any resources, and remove any scheduled license checks. It is safe to call this method if this license manager was not started.

See Also:

start()

doStart

protected void doStart()

doStop

protected void doStop()

configuredLicense

public License configuredLicense()

registerOrValidateAddOnLicense

public License registerOrValidateAddOnLicense(String license)
                                       throws InvalidLicenseException

Validate the supplied license, or if blank register a new trial license. It is intended to be used by AddonLicenseManager or licenseManager licensePurpose is not PRIMARY.

Parameters:

license - the new license string to be persisted in the topic; may be empty if there is no updated license

Returns:

the summary of the current license; never null

Throws:

ExpiredLicenseException - if the supplied or stored license has expired

InvalidLicenseException - if the supplied or stored license is not valid

registerOrValidateLicense

public License registerOrValidateLicense(String license)
                                  throws InvalidLicenseException

Validates a supplied CP or 'CP for CC' license and persists it in LicenseStore. If no input is provided, selects a valid stored license or generates a TRIAL/DEV CP license if allowed. When input is provided: - Valid CP → stored under CP if have greater expiry (does not overwrite 'CP for CC'); used as active. - Valid 'CP for CC' → stored under 'CP for CC' if have greater expiry (does not overwrite CP); used as active. - Invalid → throws InvalidLicenseException, which can occur due to: - input JWT claims is invalid - input signed JWT with invalid expiry format → falls back to stored licenses; if none active, throws InvalidLicenseException. - Returns the valid stored CP license; otherwise the valid stored 'CP for CC' license. When input is not provided: - Returns the valid stored CP license; otherwise the valid stored 'CP for CC' license. - If neither exists and no CP license was ever stored, generates and persists a TRIAL/DEV CP license, then returns it.

Parameters:

license - CP or CP for CC license string; may be blank

Returns:

The active primary license to use, preferring CP over 'CP for CC'; never null

Throws:

ExpiredLicenseException - if the no active license provided and all stored licenses are expired

InvalidLicenseException - if the license is invalid or all stored licenses are invalid

registerOrValidateMultiLicense

public List<License> registerOrValidateMultiLicense(String license,
                                                    boolean skipTrialLicenseGeneration)
                                             throws InvalidLicenseException

Validates a supplied CP or 'CP for CC' license, persists it in LicenseStore. and returns all active primary licenses. Optionally skips TRIAL/DEV license generation. Verification and storage: - Accepts CP or 'CP for CC' license; validates and stores under its scope. - Invalid input → throws InvalidLicenseException. - Signed JWT with invalid expiry format → falls back to stored licenses; if none active, throws InvalidLicenseException. Trial/Dev generation: - Generates and persists a TRIAL/DEV CP license only when skipTrialLicenseGeneration is false, and no CP license was ever stored, and no active CP license is configured. Return: - Immutable list of active primary licenses: CP only, CP for CC only, or both. It will never be empty. It will throw an InvalidLicenseException if no active license found.

Parameters:

license - CP or 'CP for CC' license; may be blank

skipTrialLicenseGeneration - when true, never generates a TRIAL/DEV license

Returns:

immutable list of active primary licenses; never null or empty list

Throws:

ExpiredLicenseException - if Stored CP license is expired and no other active license is available.

InvalidLicenseException - if the configured license is invalid, or Stored CP license is invalid and no other active license is available.

readLicense

protected final License readLicense(PublicKey publicKey,
                                    String licenseStr,
                                    boolean stored)
                             throws InvalidLicenseException

Throws:

InvalidLicenseException

generateLicense

protected License generateLicense(long now)
                           throws InvalidLicenseException

Throws:

InvalidLicenseException

hasOnlySingleNodeClusters

protected boolean hasOnlySingleNodeClusters()

notifyLicense

protected final void notifyLicense(License newLicense,
                                   License oldLicense,
                                   List<License> finalInstalledLicense,
                                   String reason)

loadPublicKey

public static PublicKey loadPublicKey()

timeUntilLicenseExpirationMs

public void timeUntilLicenseExpirationMs(long timeMs)

timeUntilLicenseExpirationMs

public long timeUntilLicenseExpirationMs()