Table of Contents

Status

Current state: Under discussionAccepted - 2.6.0 contains describe and alter functionality, resolve is pending for a future release.

Discussion thread: TODO here

JIRA: KAFKA-7740

Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).

Motivation

Quota management via Admin Client has gone through a couple drafts of proposals (KIP -248, KIP-422). While improvements have been made to the Admin interface for configuration handling, fitting quotas into the API is awkward as they don't fit the natural key-value pairing, nor is the configuration output expressive enough to return all useful information. Therefore, it'd be beneficial to have a quota-native API for managing quotas, which would offer an intuitive and less error-prone interface, convey additional information beyond what the configuration APIs provide, and enable for future extensibility as quotas types are added or evolved.

Background

By default, quotas are defined in terms of a user and client ID, where the user acts as an opaque principal name, and the client ID as a generic group identifier. When setting quotas, an administrator has flexibility in how it specifies the user and client ID for which the quota applies, where the user and client ID may be specifically named, indicated as a default, or omitted entirely. Since quotas have flexible configurations, there is a method for resolving the quotas that apply to a request: a hierarchy structure is used, where the most specific defined quota will be matched to a request's user and client ID.

As represented by the current ZK node structure, the order in which quotas are matched are as follows, in order of from highest priority to lowest (note <user> is a specified user principal, <client-id> is a specified client ID, and <default> is a special default user/client ID that matches to all users or clients IDs):

...

As such, reasoning around quotas can be complex, as it's not immediately obvious which quotas may apply to a given user and/or client ID. Providing descriptive information about how quotas are matched is the first goal of this KIP. Likewise, retrieving and modifying quota values can be done in a more expressive and robust way, which is the second goal of the KIP.

APIs

In order to clearly specify the APIs, let's first disambiguate some terminology: Every client request that is processed is associated with a quota entity, which is a map of entity types to their corresponding entity names for the request. Using the current entity types, an entity is of the form {user=test-user, client-id=test-client}, where user and client-id are the types, and test-user and test-client are the names. However, when specifying a quota configuration entry, only a subset of the entity types need to be provided, which is referred to as an entity match, for example, {user=<default>}.

...

The config-centric mode describes what is exactly specified for the configuration for the given entity match. However, it would also be useful to also be able to determine which matches have configuration values defined, so the presence of a filter is used for gathering information about the entity matches that the administrator is interested in. This is DescribeQuotas DescribeClientQuotas.
The entity-centric mode describes what quotas apply to an entity. Note that an entity may match to various configuration entries depending on how the quotas are specified, e.g. the producer byte rate may be specified for the user, but the consumer byte rate for the client ID. Since it may not be clear how quotas were matched for an entity from the configuration, additional information should be returned to provide more context. This is DescribeEffectiveQuotas ResolveClientQuotas.

Altering quotas only works on a config-centric manner, and therefore doesn't need distinguishing. For a given entity match, the administrator should be able to specify which quotas apply, or alternatively remove existing quotas so they no longer match. This is AlterQuotas AlterClientQuotas.

The quota values are of type Double, which presents a complication in that the RPC protocol doesn't support floating point values. To accommodate this, RPC protocol message type 'double' will be added, which will serialize doubles according to the IEEE 754 floating-point "double format" bit layout.

Types Rationale

While there's two defined entity types in AK, a server-side plugin mechanism allows for further expansion. Likewise, as use cases evolve, finer-grained quota control may be necessary. Therefore, entity types should not be statically bound to publicly defined constants, and instead the API should support flexible entity types by interpreting them as a String identifier. Any entity types that the broker doesn't understand should throw an IllegalArgumentException back to the client.

The quota types (producer byte rate, consumer byte rate, etc.) and units should also be given the same consideration. The possible quota applications may expand in the future, and the API shouldn't lock in which quota types are accessible. Modification of quota types/units that types that are unknown should also fail with error.

Since a fixed set of entity types aren't defined, an entity should be represented by a Map<String, String>, which maps an entity type to the entity name.

Public Interfaces

Admin client calls will be added to correspond to describeQuotas DescribeClientQuotas, describeEffectiveQuotas ResolveClientQuotas, and alterQuotas AlterClientQuotas, with supporting types defined in the common.quotas package.

Common types in package org.apache.kafka.common.quota

...

(2.6.0)

Code Block

language	java

/**
 * Describes a fully-qualified entity client quota entity, which is a mapping of entity types to their names.
 */
public class QuotaEntityClientQuotaEntity {

    /**
     * TypeThe type of an entity entry. Note there may be additional types, these are defined for convenience.
     */
    public static final String USER = ..."user";
    public static final String CLIENT_ID = ..."client-id";

    /**
     * RepresentsConstructs thea defaultquota nameentity for the given antypes entity,and inames.e. theIf entity that's matcheda name is null,
     * when an exact match isn't found then it is mapped to the built-in default entity name.
     */
    public final* static@param String QUOTA_ENTITY_NAME_DEFAULT = ...;

    /**entries maps entity type to its name
     */
 `entries` describes the fully-qualified entity. The key is a {@code Type} string, howeverpublic ClientQuotaEntity(Map<String, String> entries);

    /**
     * there@return maymap alsoof existentity keystype thatto areits notname
 enumerated by {@code Type} that*/
 still apply, e.g.
 public Map<String, String> entries();
}

/**
 * the server may internally associate another type. When querying entities, it's necessaryDescribes a component for applying a client quota filter.
 */
public class ClientQuotaFilterComponent {

     /**
 to return all quota types* becauseConstructs quotaand valuesreturns fora thesefilter typescomponent maythat influenceexactly matches the provided effectiveentity
     * quotaname value.for However,the whenentity alteringtype.
 a quota, any types that aren't specified must be able *
     * to@param entityType bethe inferredentity bytype the server,filter otherwisecomponent an error is returned.applies to
     *
 @param entityName the entity *name For example, {("CLIENT_ID" -> "test-client"),that's matched exactly
     */
    public static ClientQuotaFilterComponent ofEntity(String entityType, String entityName);

    /**
   ("USER" -> "test-user"),
     *         * Constructs and returns a filter component that matches the built-in default entity name
     * for ("GROUP" -> "internal-group")}the entity type.
     */
    public QuotaEntity(Map<String, String> entries);
}

/**
 * Describes quota types.
 */
public class QuotaType {
* @param entityType the entity type the filter component applies to
     */**
    public *static TheClientQuotaFilterComponent type of quota to apply. Note there may be additional types, these are defined for convenience.
     */
    public static final String CONSUMER_BYTE_RATE = ...;ofDefaultEntity(String entityType);

    /**
     * Constructs and returns a filter component that matches any specified name for the
     * entity type.
    public static*
 final String PRODUCER_BYTE_RATE = ...;
* @param entityType the publicentity statictype finalthe Stringfilter REQUEST_PERCENTAGEcomponent = ...;
}

/**applies to
 * Describes a quota entity filter.
 */
public class QuotaFilter {
    public static finalClientQuotaFilterComponent ofEntityType(String RULE_EXACT = ...entityType);

    /**
     * A@return filteringthe rulecomponent's to be applied.entity type
     */
    public * @paramString entityType();

 the entity type the rule applies to /**
     * @param@return rulethe theoptional rulematch tostring, applywhere:
     * @param match the non-null string that's applied by   if present, the rule name that's matched exactly
     */
    public QuotaFilter(QuotaEntity.Type entityType, String rule, String match);
}

DescribeQuotas:

Code Block

language	java

public class DescribeQuotasOptions extends AbstractOptions<DescribeQuotasOptions> {if empty, matches the default name
    // Empty.
}

/**
 * The result of the {@link Admin#describeQuotas(Collection<QuotaFilter>, DescribeQuotasOptions)} call.
 */
public class DescribeQuotasResult {

*         if null, matches any specified name
     */**
    public Optional<String> match();
}

/**
 Maps* anDescribes entitya toclient itsquota configured quota value(s). Note if no value is defined for a quotaentity filter.
 */
public class ClientQuotaFilter {

    /**
     * typeA forfilter thatto entity's config, then it is not included in the resulting value mapbe applied to matching client quotas.
     *
     * @param entitiescomponents the collectioncomponents ofto entities that matched the filterfilter on
     * @param strict whether the filter only includes specified components
     */
    publicprivate DescribeQuotasResultClientQuotaFilter(KafkaFuture<Map<QuotaEntity,Collection<ClientQuotaFilterComponent> Map<Stringcomponents, Long>>>boolean entitiesstrict);

    /**
     * ReturnsConstructs and returns a map from quotaquota filter that matches all provided components. Matching entities
     * with entity totypes that aare futurenot whichspecified canby bea usedcomponent towill checkalso thebe statusincluded ofin the operationresult.
     */
    public KafkaFuture<Map<QuotaEntity, Map<String, Long>>> entities();
}

public interface Admin extends AutoCloseable {
    ...* @param components the components for the filter
     */
    public static ClientQuotaFilter contains(Collection<ClientQuotaFilterComponent> components);

    /**
     * Describes all entities matching all provided filters (logical AND) that have at least one
     * quota value defined Constructs and returns a quota filter that matches all provided components. Matching entities
     * with entity types that are not specified by a component will *not* be included in the result.
     *
     * @param filters filtering rules to apply to matching entitiescomponents the components for the filter
     */
    public * @param options the options to usestatic ClientQuotaFilter containsOnly(Collection<ClientQuotaFilterComponent> components);

    /**
     * @return result containingConstructs and returns a quota filter that matches all matchingconfigured entities.
     */
    DescribeQuotasResultpublic describeQuotas(Collection<QuotaFilter> filters, DescribeQuotasOptions optionsstatic ClientQuotaFilter all();
}

DescribeEffectiveQuotas:

Code Block

language	java

public class DescribeEffectiveQuotasOptions extends AbstractOptions<DescribeEffectiveQuotasOptions> {

    /**
     * Whether@return to exclude the list of overridden values for every quota type in the result.the filter's components
     */
    public Collection<ClientQuotaFilterComponent> components();

    /**
     * @return whether the filter is strict, i.e. only includes specified components
     */
    public DescribeEffectiveQuotasOptionsboolean setOmitOverriddenValuesstrict(boolean omitOverriddenValues);
}

/**
 * The result of the {@link Admin#describeEffectiveQuotas(Collection<QuotaEntity>, DescribeEffectiveQuotasOptions)} call Describes a configuration alteration to be made to a client quota entity.
 */
public class DescribeEffectiveQuotasResultClientQuotaAlteration {

     /**public static class Op {

     * Information about a/**
 specific quota configuration entry.
     */
 @param key the publicquota classtype Entryto {alter
         /*** @param value if set then the existing value is updated,
         * @param source the entity source for the value
      otherwise if null, *the @paramexisting value the non-null valueis cleared
         */
        public EntryOp(QuotaEntityString sourcekey, LongDouble value);

    }

    /**
     * Information about the value* for@return athe quota type.
 to alter
         */
        public class Value {String key();

        /**
         * @param@return entryif theset quotathen entry
the existing value is updated,
     * @param overriddenEntries all values* that are overridden due to being lower in
 otherwise if null, the existing value is cleared
 *        */
        public Double value();
    }

    specificity,private orfinal nullClientQuotaEntity ifentity;
 not requested
  private final Collection<Op> ops;

    /*/*
     * @param entity public Value(Entry entry, List<Entry> overriddenEntries);the entity whose config will be modified
    }

    /** * @param ops the alteration to perform
     */
 Maps a collection ofpublic entities to their effective quota values.ClientQuotaAlteration(ClientQuotaEntity entity, Collection<Op> ops);

     /**
     * @param@return config the quotaentity configurationwhose forconfig thewill requestedbe entitiesmodified
     */
    public DescribeEffectiveQuotasResult(Map<QuotaEntity, KafkaFuture<Map<String, Value>>> configClientQuotaEntity entity();

    /**
     * Returns@return athe mapalteration fromto quotaperform
 entity to a future which*/
  can be usedpublic to check the status of the operation.Collection<Op> ops();
}

DescribeClientQuotas (2.6.0)

Code Block

language	java

public class DescribeClientQuotasOptions extends AbstractOptions<DescribeClientQuotasOptions> {
    // */
    public Map<QuotaEntity, KafkaFuture<Map<String, Value>>> config();Empty.
}

/**
 * The result of the {@link Admin#describeClientQuotas(Collection, DescribeClientQuotasOptions)} call.
 */
public class DescribeClientQuotasResult {

    /**
     * ReturnsMaps aan futureentity whichto succeedsits onlyconfigured if all quota descriptions succeed.
     */
    public KafkaFuture<Void> all();
}

public interface Admin extends AutoCloseable {
    ...

    /**
     * Describes the effective quotas for the provided entitiesvalue(s). Note if no value is defined for a quota
     * type for that entity's config, then it is not included in the resulting value map.
     *
     * @param entities future for the collection of entities tothat describematched the effective quotas forfilter
     */
 @param options the options to use public DescribeClientQuotasResult(KafkaFuture<Map<ClientQuotaEntity, Map<String, Double>>> entities);

    /**
     * @return Returns a map from quota entity to a future which can be used to check the effectivestatus quotasof for the entitiesoperation.
     */
    DescribeEffectiveQuotasResult describeEffectiveQuotas(Collection<QuotaEntity> entitiespublic KafkaFuture<Map<ClientQuotaEntity, Map<String, DescribeEffectiveQuotasOptionsDouble>>> optionsentities();
}

AlterQuotas

Code Block

language	java
title	AlterQuotas

public class AlterQuotasEntry

public interface Admin extends AutoCloseable {
    public...

 class Op {
        /**
     * Describes all entities * @parammatching key the quotaprovided typefilter andthat unitshave toat alter
least one client quota configuration
     * @param value ifdefined.
 set then the existing value is updated,
  * <p>
       * The following exceptions can be anticipated when calling {@code get()} on the future otherwise if null, the existing value is cleared
    from the
     * returned {@link DescribeClientQuotasResult}:
     */ <ul>
     *   public Op(String type, Long value);
    }

<li>{@link org.apache.kafka.common.errors.ClusterAuthorizationException}
     /**
   If the *authenticated @paramuser entitydidn't thehave entitydescribe whoseaccess configto will be modifiedthe cluster.</li>
     * @param ops the alteration to perform - if value is set, then the existing value is updated,
     *      <li>{@link org.apache.kafka.common.errors.InvalidRequestException}
     *   If the request details are invalid. e.g., an invalid entity type was specified.</li>
     *   <li>{@link org.apache.kafka.common.errors.TimeoutException}
     * otherwise if null,If the existingrequest valuetimed isout cleared
before the describe could  *finish.</li>
    public AlterQuotasEntry(QuotaEntity entity, Collection<Op> ops);
}

public class AlterQuotasOptions extends AbstractOptions<AlterQuotasOptions> {
    /*** </ul>
     * <p>
     * SetsThis whetheroperation theis requestsupported shouldby bebrokers validatedwith without altering the configsversion 2.6.0 or higher.
     */
    public AlterQuotasOptions validateOnly(boolean validateOnly);
}

/**
 *@param Thefilter resultthe offilter theto {@link Admin#alterQuotas(Collection<AlterQuotasEntry>, AlterQuotasOptions)} call.
 *
 * The API of this class is evolving, see {@link Admin} for details.
 */
public class AlterQuotasResult {
    public AlterQuotasResult(Map<QuotaEntity, KafkaFuture<Void>> futures);

    /**
     * Returns a map from quota entity to a future which can be used to check the status of the operation.
     */
    public Map<QuotaEntity, KafkaFuture<Void>> values()apply to match entities
     * @param options the options to use
     * @return the DescribeClientQuotasResult containing the result
     */
    DescribeClientQuotasResult describeClientQuotas(ClientQuotaFilter filter, DescribeClientQuotasOptions options);
}

ResolveClientQuotas (pending future release)

Code Block

language	java

public class ResolveClientQuotasOptions extends AbstractOptions<ResolveClientQuotasOptions> {
    // Empty.
}

/**
 * The result of the {@link Admin#resolveClientQuotas(Collection, ResolveClientQuotasOptions)} call.
 */
public class ResolveClientQuotasResult {;

    /**
     * ReturnsInformation about a future which succeeds only if all specific quota alterationsconfiguration succeedentry.
     */
    public KafkaFuture<Void> all();
}

public interface Admin extends AutoCloseableclass Entry {
    ...

    /**
         * Alters@param source the quotasentity as specifiedsource for the entries.value
     *
     * @param alterationsvalue the alterations to performnon-null value
     * @return the result of the alterations */
     */
   public AlterQuotasResult alterQuotasEntry(Collection<AlterQuotasEntry>QuotaEntity entriessource, AlterQuotasOptionsDouble optionsvalue);
}

kafka-quotas.sh/QuotasCommand:

A QuotasCommand would be constructed with an associated bin/kafka-quotas.sh script for managing quotas via command line, and would have three modes of operation, roughly correlating to each of the API calls:

List: Lists the quota entities for the given entity specification and their corresponding quota values, as explicitly specified in the configuration. The user may provide explicit entity types+names, or a pattern to apply to an entity type find matching entity names. If an entity type is omitted from the input, it is treated as a wildcard.
Describe: Describes the effective quotas for an entity, including contextual information about how those quotas were derived. This includes what configuration entries matched to the entity and, if requested, the overridden, less-specific matches for the entity.
Alter: Modifies a quota configuration entry in an incremental manner, i.e. specify which entries to add, update, and/or remove.

Flags

Various flags will be used to accomplish these operations.

Common flags:
--bootstrap-server: The standard bootstrap server.
--command-config: Property file for the Admin client.

Operations (mutually exclusive):
--list: Lists the entities that match the given specification, and prints out their configuration values.
--describe: Describes the effective quota values for an entity.
--alter: Alters the configuration for the given specification.

Entity specification flags (common to all):
--names: Comma-separated list of type=name pairs, e.g. "user=some-user,client-id=some-client-id"
--defaults: Comma-separated list of entity types with the default name, e.g. "defaults=user,client-id" (Note a separate flag is necessary since names are opaque.)

Exclusive to --list:
--prefix: Comma-separated prefix=name pairs, e.g. "user=test-".

Exclusive to --describe:
--show-overridden: Whether to show overridden config entries.

Exclusive to --alter:
--add: Comma-separated list of entries to add or update to the configuration, in format "name:unit=value".
--delete: Comma-separated list of entries to remove from the configuration, in format "name:unit".
--validate-only: If set, validates the alteration but doesn't perform it.

Output

In general, the output of the entities will be of the form: {entity-type=entity-name, ...}, where entity-name is sanitized for output since it is an opaque string. When displaying configuration values, the form: quota-name:quota-unit=quota-value.

List:

Code Block

$./bin/kafka-quotas.sh --bootstrap-server localhost:9092 --list \
                       --names=client-id=my-client

{user=user-two, client-id=my-client}
consumer_byte_rate_shares=200
producer_byte_rate=10000000

{user=user-one, client-id=my-client}
producer_byte_rate_broker_bps=2000000

{user=<default>, client-id=my-client}
consumer_byte_rate_shares=100
producer_byte_rate_broker_bps=500000

$./bin/kafka-quotas.sh --bootstrap-server localhost:9092 --list \
                       --prefix=user=user-

{user=user-two, client-id=my-client}
consumer_byte_rate_shares=200
producer_byte_rate=10000000

{user=user-one, client-id=my-client}
producer_byte_rate_broker_bps=2000000

Describe:

Code Block

$./bin/kafka-quotas.sh --bootstrap-server localhost:9092 --describe \
                       --names=user=user-one,client-id=my-client

consumer_byte_rate_shares=200 {user=user-one, client-id=my-client}
producer_byte_rate=10000000 {user=user-one, client-id=my-client}
producer_byte_rate_broker_bps=500000 {user=<default>, client-id=my-client}

$./bin/kafka-quotas.sh --bootstrap-server localhost:9092 --describe \
                       --names=user=user-two,client-id=my-client    \
                       --show-overridden

consumer_byte_rate_shares=100 {user=<default>, client-id=my-client}
producer_byte_rate_broker_bps=2000000 {user=user-two, client-id=my-client}
*producer_byte_rate_broker_bps=500000 {user=<default>, client-id=my-client}

Alter:

Code Block

$./bin/kafka-quotas.sh --bootstrap-server localhost:9092 --describe \
                       --names=client-id=my-client --defaults=user  \
                       --add=producer_byte_rate_shares=100          \
                       --delete=producer_byte_rate_broker_bps

<no output on success>

$./bin/kafka-quotas.sh --bootstrap-server localhost:9092 --list     \
                       --names=client-id=my-client --defaults=user

{user=<default>, client-id=my-client}
consumer_byte_rate_shares=100
producer_byte_rate_shares=100

...

    }

    /**
     * Information about the value for a quota type.
     *
     * NOTE: We maintain a `Value` class because additional information may be added, e.g.,
     *       a list of overridden entries.
     */
    public class Value {
        /**
         * @param entry the quota entry
         */
        public Value(Entry entry);
    }

    /**
     * Maps a collection of entities to their resolved quota values.
     *
     * @param config the quota configuration for the requested entities
     */
    public ResolveClientQuotasResult(Map<QuotaEntity, KafkaFuture<Map<String, Value>>> config);

    /**
     * Returns a map from quota entity to a future which can be used to check the status of the operation.
     */
    public Map<QuotaEntity, KafkaFuture<Map<String, Value>>> config();

    /**
     * Returns a future which succeeds only if all quota descriptions succeed.
     */
    public KafkaFuture<Void> all();
}

public interface Admin extends AutoCloseable {
    ...

    /**
     * Resolves the effective quota values for the provided entities.
     *
     * @param entities the entities to describe the resolved quotas for
     * @param options the options to use
     * @return the resolved quotas for the entities
     */
    ResolveClientQuotasResult resolveClientQuotas(Collection<QuotaEntity> entities, ResolveClientQuotasOptions options);
}

AlterClientQuotas (2.6.0)

Code Block

language	java
title	AlterQuotas

/**
 * Options for {@link Admin#alterClientQuotas(Collection, AlterClientQuotasOptions)}.
 *
 * The API of this class is evolving, see {@link Admin} for details.
 */
public class AlterClientQuotasOptions extends AbstractOptions<AlterClientQuotasOptions> {

    /**
     * Returns whether the request should be validated without altering the configs.
     */
    public boolean validateOnly();

    /**
     * Sets whether the request should be validated without altering the configs.
     */
    public AlterClientQuotasOptions validateOnly(boolean validateOnly);
}

/**
 * The result of the {@link Admin#alterClientQuotas(Collection, AlterClientQuotasOptions)} call.
 *
 * The API of this class is evolving, see {@link Admin} for details.
 */
@InterfaceStability.Evolving
public class AlterClientQuotasResult {

    /**
     * Maps an entity to its alteration result.
     *
     * @param futures maps entity to its alteration result
     */
    public AlterClientQuotasResult(Map<ClientQuotaEntity, KafkaFuture<Void>> futures);

    /**
     * Returns a map from quota entity to a future which can be used to check the status of the operation.
     */
    public Map<ClientQuotaEntity, KafkaFuture<Void>> values();

    /**
     * Returns a future which succeeds only if all quota alterations succeed.
     */
    public KafkaFuture<Void> all();
}

public interface Admin extends AutoCloseable {
    ...

    /**
     * Alters client quota configurations with the specified alterations.
     * <p>
     * Alterations for a single entity are atomic, but across entities is not guaranteed. The resulting
     * per-entity error code should be evaluated to resolve the success or failure of all updates.
     * <p>
     * The following exceptions can be anticipated when calling {@code get()} on the futures obtained from
     * the returned {@link AlterClientQuotasResult}:
     * <ul>
     *   <li>{@link org.apache.kafka.common.errors.ClusterAuthorizationException}
     *   If the authenticated user didn't have alter access to the cluster.</li>
     *   <li>{@link org.apache.kafka.common.errors.InvalidRequestException}
     *   If the request details are invalid. e.g., a configuration key was specified more than once for an entity.</li>
     *   <li>{@link org.apache.kafka.common.errors.TimeoutException}
     *   If the request timed out before the alterations could finish. It cannot be guaranteed whether the update
     *   succeed or not.</li>
     * </ul>
     * <p>
     * This operation is supported by brokers with version 2.6.0 or higher.
     *
     * @param entries the alterations to perform
     * @return the AlterClientQuotasResult containing the result
     */
    AlterClientQuotasResult alterClientQuotas(Collection<ClientQuotaAlteration> entries, AlterClientQuotasOptions options);
}

kafka-configs.sh/ConfigCommand (2.6.0)

As a result of introducing the APIs, the ConfigCommand will be updated to support the users and clients entity types when using the --bootstrap-server option. The modification to ConfigCommand was adopted in KIP-543, and usage will remain unchanged from the original --zookeeper functionality.

kafka-client-quotas.sh/ClientQuotasCommand (pending future release)

A ClientQuotasCommand would be constructed with an associated bin/kafka-client-quotas.sh script for managing quotas via command line, and would have three modes of operation, roughly correlating to each of the API calls:

Describe: Describes the quota entities for the given entity specification and their corresponding quota values, as explicitly specified in the configuration. The user may provide explicit entity types+names, or a pattern to apply to an entity type find matching entity names. If an entity type is omitted from the input, it is treated as a wildcard.
Resolve: Resolves the effective quotas for an entity, including contextual information about how those quotas were derived. This includes what configuration entries matched to the entity.
Alter: Modifies a quota configuration entry in an incremental manner, i.e. specify which entries to add, update, and/or remove.

Flags

Various flags will be used to accomplish these operations.

Common flags:
--bootstrap-server: The standard bootstrap server.
--command-config: Property file for the Admin client.

Operations (mutually exclusive):
--describe: Describes the entities that match the given specification, and prints out their configuration values.
--resolve: Resolves the effective quota values for an entity.
--alter: Alters the configuration for the given specification.

Entity specification flags (common to all):
--names: Comma-separated list of type=name pairs, e.g. "user=some-user,client-id=some-client-id"
--defaults: Comma-separated list of entity types with the default name, e.g. "defaults=user,client-id" (Note a separate flag is necessary since names are opaque.)

Exclusive to --describe: None.

Exclusive to --resolve: None.

Exclusive to --alter:
--add: Comma-separated list of entries to add or update to the configuration, in format "name=value".
--delete: Comma-separated list of entries to remove from the configuration, in format "name".
--validate-only: If set, validates the alteration but doesn't perform it.

Input

When specifying configuration entries, the form: quota-name[=quota-value] is used.

Output

In general, the output of the entities will be of the form: {entity-type=entity-name, ...}, where entity-name is sanitized for output since it is an opaque string. When displaying configuration values, the form: quota-name=quota-value.

Describe:

Code Block

$./bin/kafka-client-quotas.sh --bootstrap-server localhost:9092 --describe \
                              --names=client-id=my-client

{user=user-one, client-id=my-client}
consumer_byte_rate=4000000
producer_byte_rate=1000000

{user=user-two, client-id=my-client}
producer_byte_rate=2000000

{user=<default>, client-id=my-client}
consumer_byte_rate=1000000
producer_byte_rate=500000

Resolve:

Code Block

$./bin/kafka-client-quotas.sh --bootstrap-server localhost:9092 --resolve \
                              --names=user=user-two,client-id=my-client

consumer_byte_rate=2000000 {user=user-two, client-id=my-client}
producer_byte_rate=500000 {user=<default>, client-id=my-client}

Alter:

Code Block

$./bin/kafka-client-quotas.sh --bootstrap-server localhost:9092 --alter   \
                              --names=client-id=my-client --defaults=user \
                              --add=consumer_byte_rate=2000000            \
                              --delete=producer_byte_rate

<no output on success>

$./bin/kafka-client-quotas.sh --bootstrap-server localhost:9092 --describe \
                              --names=client-id=my-client --defaults=user

{user=<default>, client-id=my-client}
consumer_byte_rate=2000000

Proposed Changes

In addition to the API changes above, the following write protocol would be implemented:

DescribeClientQuotas (2.6.0)

Code Block
{ "apiKey": 48, "type": "request", "name": "DescribeClientQuotasRequest", "validVersions": "

In addition to the API changes above, the following write protocol would be implemented:

DescribeQuotas:

Code Block

{
  "apiKey": 48,
  "type": "request",
  "name": "DescribeQuotasRequest",
  "validVersions": "0",
  "flexibleVersions": "none",
  "fields": [
    { "name": "Filter", "type": "[]QuotaFilterData", "versions": "0+",
      "about": "Filters to apply to quota entities.", "fields": [
      { "name": "EntityType", "type": "string", "versions": "0+",
        "about": "The entity type that the filter applies to." },
      { "name": "Rule", "type": "string", "versions": "0+",
        "about": "The rule the filter performs." },
      { "name": "Match", "type": "string", "versions": "0+",
        "about": "The string to apply the rule against." }
    ]}
  ]
}

{
  "apiKey": 48,
  "type": "response",
  "name": "DescribeQuotasResponse",
  "validVersions": "0",
  "flexibleVersions": "none",
  "fields": [
    { "name": "ThrottleTimeMs", "type": "int32", "versions": "0+",
      "about": "The duration in milliseconds for which the request was throttled due to a quota violation, or zero if the request did not violate any quota." },
    { "name": "Entry", "type": "[]EntryData", "versions": "0+",
      "about": "A result entry.", "fields": [
      { "name": "ErrorCode", "type": "int16", "versions": "0+",
        "about": "The error code, or `0` if the quota description succeeded." },
      { "name": "ErrorMessage", "type": "string", "versions": "0+", "nullableVersions": "0+",
        "about": "The error message, or `null` if the quota description succeeded." },
      { "name": "Entity", "type": "[]QuotaEntityData", "versions": "0+",
        "about": "The quota entity description.", "fields": [
        { "name": "EntityType", "type": "string", "versions": "0+",
          "about": "The entity type." },
        { "name": "EntityName", "type": "string", "versions": "0+",
          "about": "The entity name." }
      ]},
      { "name": "Type", "type": "string", "versions": "0+",
        "about": "The quota type." },
      { "name": "Value", "type": "int64", "versions": "0+",
        "about": "The quota value." }
    ]}
  ]
}

DescribeEffectiveQuotas:

Code Block

{
  "apiKey": 49,
  "type": "request",
  "name": "DescribeEffectiveQuotasRequest",
  "validVersions": "0",
  "flexibleVersions": "none",
  "fields": [
    { "name": "Entity", "type": "[]QuotaEntityData", "versions": "0+",
      "about": "The quota entity description.", "fields": [
      { "name": "EntityType", "type": "string", "versions": "0+",
        "about": "The entity type." },
      { "name": "EntityName", "type": "string", "versions": "0+",
        "about": "The entity name." }
    ]},
    { "name": "OmitOverriddenValues", "type": "bool", "versions": "0+",
      "about": "Whether to exclude the list of overridden values for every quota type." }
  ]
}

{
  "apiKey": 49,
  "type": "response",
  "name": "DescribeEffectiveQuotasResponse",
  "validVersions": "0",
  "flexibleVersions": "none",
  "fields": [
    { "name": "ThrottleTimeMsComponents", "type": "int32[]ComponentData", "versions": "0+",
      "about": "TheFilter durationcomponents in milliseconds for which the request was throttled due to a quota violation, or zero if the request did not violate any quota." },
    to apply to quota entities.", "fields": [
      { "name": "EntryEntityType", "type": "[]QuotaEntryDatastring", "versions": "0+",
        "about": "EffectiveThe quota entries.", "fields": [
      entity type that the filter component applies to." },
      { "name": "ErrorCodeMatchType", "type": "int16int8", "versions": "0+",
        "about": "The error code, or `0` if the effective quota description succeededHow to match the entity {0 = exact name, 1 = default name, 2 = any specified name}." },
      { "name": "ErrorMessageMatch", "type": "string", "versions": "0+", "nullableVersions": "0+",
        "about": "The string errorto match messageagainst, or `null`null if theunused effectivefor quotathe descriptionmatch succeededtype." },
    ]},
    { "name": "QuotaEntityStrict", "type": "[]QuotaEntitybool", "versions": "0+",
        "about": "EffectiveWhether quota entries.", "fields": [
        { "name": "EntityType",the match is strict, i.e. should exclude entities with unspecified entity types." }
  ]
}

{
  "apiKey": 48,
  "type": "stringresponse",
  "versionsname": "0+DescribeClientQuotasResponse",
  "validVersions": "0",
       "aboutflexibleVersions": "The entity type." }none",
    "fields": [
    { "name": "EntityNameThrottleTimeMs", "type": "stringint32", "versions": "0+",
          "about": "The entityduration name." }
      ]},
      { "in milliseconds for which the request was throttled due to a quota violation, or zero if the request did not violate any quota." },
    { "name": "QuotaValuesErrorCode", "type": "[]QuotaValueDataint16", "versions": "0+",
        "about": "QuotaThe configurationerror values."code, "fields": [
    or `0` if the quota description succeeded." },
    { "name": "TypeErrorMessage", "type": "string", "versions": "0+",
   "nullableVersions": "0+",
       "about": "The error message, or `null` if the quota description typesucceeded." },
        { "name": "EntryEntries", "type": "[]ValueEntryDataEntryData", "versions": "0+",
   "nullableVersions": "0+",
       "about": "QuotaA valueresult entriesentry.", "fields": [
          { "name": "QuotaEntityEntity", "type": "[]ValueQuotaEntityEntityData", "versions": "0+",
            "about": "EffectiveThe quota entriesentity description.", "fields": [
            { "name": "EntityType", "type": "string", "versions": "0+",
              "about": "The entity type." },
            { "name": "EntityName", "type": "string", "versions": "0+",
 "nullableVersions": "0+",
            "about": "The entity name, or null if the default." }
          ]},
          { "name": "ValueValues", "type": "int64[]ValueData", "versions": "0+",
            	"about": "The quota configuration valuevalues for the entity." }, "fields": [
        ]}
      ]}{ "name": "Key", "type": "string", "versions": "0+",
    ]}
    ]
}

AlterQuotas:

Code Block

{
  "apiKeyabout": 50,
  "type": "request""The quota configuration key." },
        { "name": "AlterQuotasRequestValue",
  "validVersionstype": "0float64",
  "flexibleVersionsversions": "none0+",
  "fields": [
        "about": "The quota configuration value." }
      ]}
    ]}
  ]
}

ResolveClientQuotas (pending future release)

Code Block

{
  "apiKey": 50,
  "type": "request",
  "{ "name": "Entry", "type": "[]EntryData", "versions": "0+",
      "about": "The quota configuration entries to alter.", "fields": [
      { "name": "QuotaEntity", "type": "[]QuotaEntity", "versions": "0+",
        "about": "The quota entity to alter.", "fields": [
        { "name": "EntityType", "type": "string", "versions": "0+",
          "about": "The entity type." },
        { "name": "EntityName", "type": "string", "versions": "0+",
          "about": "The name of the entity." }
      ]},
      { "name": "Op", "type": "[]OpData", "versions": "0+",
        "about": "An individual quota configuration entry to alter.", "fields": [
        { "name": "Type", "type": "string", "versions": "0+",
          "about": "The quota type." },
        { "name": "Value", "type": "int64", "versions": "0+",ResolveClientQuotasRequest",
  "validVersions": "0",
  "flexibleVersions": "none",
  "fields": [
    { "name": "Entity", "type": "[]QuotaEntityData", "versions": "0+",
      "about": "The quota entity description.", "fields": [
      { "name": "EntityType", "type": "string", "versions": "0+",
        "about": "The entity type." },
      { "name": "EntityName", "type": "string", "versions": "0+",
        "about": "The entity name." }
    ]}
  ]
}

{
  "apiKey": 50,
  "type": "response",
  "name": "ResolveClientQuotasResponse",
  "validVersions": "0",
  "flexibleVersions": "none",
  "fields": [
    { "name": "ThrottleTimeMs", "type": "int32", "versions": "0+",
      "about": "The duration in milliseconds for which the request was throttled due to a quota violation, or zero if the request did not violate any quota." },
    { "name": "Entry", "type": "[]QuotaEntryData", "versions": "0+",
      "about": "Resolved quota entries.", "fields": [
      { "name": "ErrorCode", "type": "int16", "versions": "0+",
        "about": "The error code, or `0` if the resolved quota description succeeded." },
      { "name": "ErrorMessage", "type": "string", "versions": "0+", "nullableVersions": "0+",
        "about": "The error message, or `null` if the resolved quota description succeeded." },
      { "name": "QuotaEntity", "type": "[]QuotaEntity", "versions": "0+",
        "about": "Resolved quota entries.", "fields": [
        { "name": "EntityType", "type": "string", "versions": "0+",
          "about": "The entity type." },
        { "name": "EntityName", "type": "string", "versions": "0+",
          "about": "The entity name." }
      ]},
      { "name": "QuotaValues", "type": "[]QuotaValueData", "versions": "0+",
        "about": "Quota configuration values.", "fields": [
        { "name": "Type", "type": "string", "versions": "0+",
          "about": "The quota type." },
        { "name": "Entry", "type": "[]ValueEntryData", "versions": "0+",
          "about": "Quota value entries.", "fields": [
          { "name": "QuotaEntity", "type": "[]ValueQuotaEntity", "versions": "0+",
            "about": "Resolved quota entries.", "fields": [
            { "name": "EntityType", "type": "string", "versions": "0+",
              "about": "The entity type." },
            { "name": "EntityName", "type": "string", "versions": "0+",
              "about": "The entity name." }
          ]},
          { "name": "Value", "type": "double", "versions": "0+",
            "about": "The quota configuration value." }
        ]}
      ]}
    ]}
  ]
}

AlterClientQuotas (2.6.0)

Code Block

{
  "apiKey": 49,
  "type": "request",
  "name": "AlterClientQuotasRequest",
  "validVersions": "0",
  "flexibleVersions": "none",
  "fields": [
    { "name": "Entries", "type": "[]EntryData", "versions": "0+",
      "about": "The quota configuration entries to alter.", "fields": [
      { "name": "Entity", "type": "[]EntityData", "versions": "0+",
        "about": "The quota entity to alter.", "fields": [
        { "name": "EntityType", "type": "string", "versions": "0+",
          "about": "The entity type." },
        { "name": "EntityName", "type": "string", "versions": "0+", "nullableVersions": "0+",
          "about": "The name of the entity, or null if the default." }
      ]},
      { "name": "Ops", "type": "[]OpData", "versions": "0+",
        "about": "An individual quota configuration entry to alter.", "fields": [
        { "name": "Key", "type": "string", "versions": "0+",
          "about": "The quota configuration key." },
        { "name": "Value", "type": "float64", "versions": "0+",
          "about": "The value to set, otherwise ignored if the value is to be removed." },
        { "name": "Remove", "type": "bool", "versions": "0+",
          "about": "Whether the quota configuration value should be removed, otherwise set." }
      ]}
    ]},
    { "name": "ValidateOnly", "type": "bool", "versions": "0+",
      "about": "Whether the alteration should be validated, but not performed." }
  ]
}

{
  "apiKey": 49,
  "type": "response",
  "name": "AlterClientQuotasResponse",
  "validVersions": "0",
  "flexibleVersions": "none",
  "fields": [
    { "name": "ThrottleTimeMs", "type": "int32", "versions": "0+",
      "about": "The duration in milliseconds for which the request was throttled due to a quota violation, or zero if the request did not violate any quota." },
    { "name": "Entries", "type": "[]EntryData", "versions": "0+",
      "about": "The quota configuration entries to alter.", "fields": [
      { "name": "ErrorCode", "type": "int16", "versions": "0+",
        "about": "The error code, or `0` if the quota alteration succeeded." },
      { "name": "ErrorMessage", "type": "string", "versions": "0+", "nullableVersions": "0+",
        "about": "The error message, or `null` if the quota alteration succeeded." },
      { "name": "Entity", "type": "[]EntityData", "versions": "0+",
        "about": "The quota entity to alter.", "fields": [
        { "name": "EntityType", "type": "string", "versions": "0+",
          "about": "The entity type." },
        { "name": "EntityName", "type": "string", "versions": "0+", "nullableVersions": "0+",
          "about": "The name of the entity, or null if the default." }
      ]}
    ]}
  ]
}

Kafka RPC 'double' support (2.6.0)

Note that, while the ByteBuffer natively supports serializing a Double, the format in which the value is serialized is not strongly specified, so the preference is to explicitly ensure a standard representation of double-precision 64-bit IEEE 754 format. This is achieved in Java using Double.doubleToRawLongBits() and Double.longBitsToDouble() and should be easily portable to other languages.

Code Block

title	clients/src/main/java/org/apache/kafka/common/utils/ByteUtils.java

    /**
     * Read a double-precision 64-bit format IEEE 754 value.
     *
     * @param buffer The buffer to read from
     * @return The long value read
     */
    public static double readDouble(ByteBuffer buffer) {
        return Double.longBitsToDouble(buffer.getLong());
    }

    /**
     * Write the given double following the double-precision 64-bit format IEEE 754 value into the buffer.
     *
     * @param value The value to write
     * @param buffer The buffer to write to
     */
    public static void writeDouble(double value, ByteBuffer buffer) {
        buffer.putLong(Double.doubleToRawLongBits(value));
    }

The protocol type definition:

Code Block

title	clients/src/main/java/org/apache/kafka/common/protocol/types/Type.java

    public static final DocumentedType DOUBLE = new DocumentedType() {
        @Override
        public void write(ByteBuffer buffer, Object o) {
          "about": "The value to set, otherwise ignored if the value is to be removed." },
 ByteUtils.writeDouble((Double) o, buffer);
        }

        @Override
   { "name": "Remove", "type": "bool", "versions": "0+",    public Object read(ByteBuffer buffer) {
          "about": "Whether the quota configuration value should be removed, otherwise set." }
return ByteUtils.readDouble(buffer);
        }

       ]} @Override
     ]},
   public { "name": "ValidateOnly", "type": "bool", "versions": "0+",
int sizeOf(Object o) {
         "about": "Whether the alterationreturn should8;
 be validated, but not performed." }
  ]
}

{
    "apiKey": 50,
  "type": "response", @Override
  "name": "AlterQuotasResponse",
  "validVersions": "0",
  "flexibleVersions": "none",
  "fields": [
      public String typeName() {
       { "name": "ThrottleTimeMs", "type": "int32", "versions": return "0+DOUBLE",;
       "about": "The duration in milliseconds for which the request was throttled due to a quota violation, or zero if the request did not violate any quota." },
    { "name": "Entry", "type": "[]EntryData", "versions": "0+", }

        @Override
        public Double validate(Object item) {
            if (item instanceof Double)
      "about": "The quota configuration entries to alter.", "fields": [          return (Double) item;
      { "name": "ErrorCode", "type": "int16", "versions": "0+", else
        "about": "The error code, or `0` if the quotathrow alteration succeeded." },
      { "name": "ErrorMessage", "type": "string", "versions": "0+", "nullableVersions": "0+",new SchemaException(item + " is not a Double.");
        }

        "about": "The error message, or `null` if the quota alteration succeeded." },@Override
        public String documentation() {
      {  "name": "QuotaEntity", "type": "[]QuotaEntity", "versions": "0+",
        "about": "The quota entity to alter.", "fields": [
 return "Represents a double-precision 64-bit format IEEE 754 value. " +
             { "name": "EntityType", "type": "string", "versions": "0+",
          "about": "The entity type." },
        { "name": "EntityName", "type": "string", "versions": "0+",
          "about": "The name of the entity." }
      ]}
    ]}
  ]
}     "The values are encoded using eight bytes in network byte order (big-endian).";
        }
    };

In generator/src/main/java/org/apache/kafka/message/MessageGenerator.java, the following operations will be used (code omitted for brevity):

Code Block

title	generator/src/main/java/org/apache/kafka/message/MessageGenerator.java

Hash code: Double.hashCode(value)

Empty value: (double) 0

Parsing a default value string: Double.parseDouble(defaultValue)

Compatibility, Deprecation, and Migration Plan

All changes would be are forward-compatible, and no migration plan is necessary. It's outside the scope of this KIP to deprecate any functionality.

Rejected Alternatives

Use existing describeConfigs/incrementalAlterConfigs for quota functionality. This falls short for a couple reasons. First, quotas entity names are more dynamic than brokers and tasks which makes them awkward to fit into generic tools which expect a single unique, distinct key, e.g. ConfigCommand. Second, there's no tool that expresses a way to get the effective quota resolved quota for an entity without some heavy engineering on the client side, which lacks extensibility and is more expensive to perform, especially over large collection of entities. Therefore, it makes sense to approach quotas as a standalone set of APIs that provide more targeted information and can properly support future extensibility.

...

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Old Version 41

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Key

Status

Motivation

Background

APIs

Types Rationale

Public Interfaces

Common types in package org.apache.kafka.common.quota

(2.6.0)

DescribeEffectiveQuotas:

DescribeClientQuotas (2.6.0)

AlterQuotas

ResolveClientQuotas (pending future release)

Flags

Output

AlterClientQuotas (2.6.0)

kafka-configs.sh/ConfigCommand (2.6.0)

kafka-client-quotas.sh/ClientQuotasCommand (pending future release)

Flags

Input

Output

Proposed Changes

DescribeClientQuotas (2.6.0)

ResolveClientQuotas (pending future release)

AlterClientQuotas (2.6.0)

Kafka RPC 'double' support (2.6.0)

Compatibility, Deprecation, and Migration Plan

Rejected Alternatives

Space shortcuts

Child pages

Page History

Versions Compared

Old Version 41

New Version Current

Key

Status

Motivation

Background

APIs

Types Rationale

Public Interfaces

Common types in package org.apache.kafka.common.quota

(2.6.0)

DescribeEffectiveQuotas:

DescribeClientQuotas (2.6.0)

AlterQuotas

ResolveClientQuotas (pending future release)

Flags

Output

AlterClientQuotas (2.6.0)

kafka-configs.sh/ConfigCommand (2.6.0)

kafka-client-quotas.sh/ClientQuotasCommand (pending future release)

Flags

Input

Output

Proposed Changes

DescribeClientQuotas (2.6.0)

ResolveClientQuotas (pending future release)

AlterClientQuotas (2.6.0)

Kafka RPC 'double' support (2.6.0)

Compatibility, Deprecation, and Migration Plan

Rejected Alternatives