Apache Helix

aid: apache-helix
name: Apache Helix
description: Apache Helix is a generic cluster management framework for partitioned and replicated distributed resources.
  It automates partition management, replication, fault tolerance, and cluster expansion for distributed systems, providing
  a REST API for cluster administration and a Java API for participant, spectator, and controller roles.
type: Index
position: Consumer
access: 3rd-Party
image: https://kinlane-productions2.s3.amazonaws.com/apis-json/apis-json-logo.jpg
tags:
- Apache
- Cluster Management
- Distributed Systems
- Open Source
- Partitioning
- Replication
created: '2026-03-16'
modified: '2026-05-19'
url: https://raw.githubusercontent.com/api-evangelist/apache-helix/refs/heads/main/apis.yml
specificationVersion: '0.19'
apis:
- aid: apache-helix:apache-helix-rest-api
  name: Apache Helix REST API
  description: REST API for managing Apache Helix clusters, instances, resources, and partition state assignments, including
    ideal state queries and external view inspection.
  humanURL: https://helix.apache.org/0.9.9-docs/tutorial_admin.html
  baseURL: http://localhost:9100
  tags:
  - Cluster Management
  - Instances
  - Partitions
  - REST
  - Resources
  properties:
  - type: Documentation
    url: https://helix.apache.org/0.9.9-docs/tutorial_admin.html
  - type: OpenAPI
    url: openapi/apache-helix-rest-openapi.yml
  - type: JSONSchema
    url: json-schema/helix-rest-cluster-schema.json
  - type: JSONLD
    url: json-ld/apache-helix-rest-context.jsonld
  - type: NaftikoCapability
    url: capabilities/rest-clusters.yaml
  - type: NaftikoCapability
    url: capabilities/rest-instances.yaml
  - type: NaftikoCapability
    url: capabilities/rest-resources.yaml
  - type: NaftikoCapability
    url: capabilities/rest-state.yaml
- aid: apache-helix:apache-helix-java-api
  name: Apache Helix Java API
  description: Java API for implementing Helix participant, spectator, and controller roles, with APIs for resource management,
    task execution, and state machine definitions.
  humanURL: https://helix.apache.org/0.9.9-docs/tutorial_participant.html
  tags:
  - Java
  - SDK
  - State Machine
  properties:
  - type: Documentation
    url: https://helix.apache.org/0.9.9-docs/tutorial_participant.html
  - type: SDK
    url: https://search.maven.org/artifact/org.apache.helix/helix-core
    title: Java SDK (Maven Central)
common:
- type: Documentation
  url: https://helix.apache.org/
- type: GettingStarted
  url: https://helix.apache.org/0.9.9-docs/Quickstart.html
- type: GitHubOrganization
  url: https://github.com/apache
- type: GitHubRepository
  url: https://github.com/apache/helix
- type: SpectralRules
  url: rules/apache-helix-spectral-rules.yml
- type: Vocabulary
  url: vocabulary/apache-helix-vocabulary.yaml
- type: Features
  data:
  - name: Automatic Partition Management
    description: Automatically assign and balance partitions across cluster nodes using pluggable rebalancer algorithms.
  - name: State Machine Framework
    description: Define custom resource state machines (e.g., Master-Slave, Leader-Standby) for any distributed service.
  - name: Fault Tolerance
    description: Detect node failures and automatically reassign partitions to maintain replication targets.
  - name: REST API
    description: HTTP REST API for cluster administration, resource management, and state inspection.
  - name: Task Framework
    description: Distributed task scheduling framework for batch jobs and recurring workflows with failure handling.
  - name: ZooKeeper Integration
    description: Uses Apache ZooKeeper as the distributed coordination backend for cluster state storage.
  - name: Spectator API
    description: Read-only API for external services to observe resource state and routing decisions.
  - name: Cloud-Aware Rebalancing
    description: Rack and zone-aware partition placement for fault-domain isolation in cloud environments.
- type: UseCases
  data:
  - name: Distributed Database Cluster Management
    description: Manage shard assignment and replication for distributed databases like DistributedLog or Espresso.
  - name: Search Index Partition Management
    description: Automatically balance and assign search index shards across a cluster of query servers.
  - name: Distributed Task Scheduling
    description: Schedule and execute distributed batch tasks with automatic retry and failure recovery.
  - name: Microservices Load Balancing
    description: Use Helix spectator API to implement client-side load balancing based on partition state.
  - name: Stateful Service Migration
    description: Perform rolling upgrades and partition migrations without service downtime.
- type: Integrations
  data:
  - name: Apache ZooKeeper
    description: ZooKeeper is the required coordination backend for Helix cluster state management.
  - name: Apache Kafka
    description: Helix is used internally by some Kafka ecosystem projects for partition management.
  - name: LinkedIn Pinot
    description: Apache Pinot uses Helix for real-time OLAP cluster partition and segment management.
  - name: LinkedIn Venice
    description: Venice feature store uses Helix for managing data store partition assignments.
maintainers:
- FN: Kin Lane
  email: [email protected]