Spring Cloud Components

• Service Discovery and Registration
• Distributed Configuration
• Control Bus
• Cluster primitives (Leader election, locks)

Spring Cloud: Angel

• Netflix Eureka
• Spring Cloud Config
• Spring Cloud Bus AMQP (Rabbitmq)
• No Cluster Implementation

Spring Cloud: Brixton

Adds

• Hashicorp Consul
• Apache Zookeeper
• Sleuth (Tracing)
• Cluster
• CoreOS etcd (Incubator)

Eureka

• Netflix OSS
• Highly Available (prefers stale data vs
  no data, AP in CAP)
• Long thresholds for registraion and
  cache refresh (30s)
• Battle tested at Netflix

Config Server and Client

• Greenfield
• HTTP API similar to Netflix Config Server
• Backed by VCS (git initially, then svn added)
• Stateless
• Uses spring-boot configuration files & semantics
• Auto-configured client

Spring Cloud Bus AMQP

• Backed by Rabbitmq
• Distributed actuator
• Post messages via /bus/* actuator endpoints
• /bus/refresh and /bus/env

Apache Zookeeper

• Consistent Distributed Coordination
  server (CP in CAP)
• Started life as a Hadoop sub-project (2007?)
• Mature, used in many companies

Spring Cloud Zookeeper Config

• Uses Apache Curator library
• Uses zookeeper to store hierarchical configuration
• Mimics Spring Cloud Config Server loading order
• Use a supervisory process like Netflix Exhibitor

Spring Cloud Zookeeper Discovery

• Uses Apache Curator Service Discovery Recipe
• Requires ephemeral nodes
  (client must maintain active connection)
• Significant contribution from 4finance
• No Bus implementation

DEMO

Consul

• From Mitchell Hashimoto, creator of Vagrant
• Multi-datacenter aware
• peer-to-peer gossip system
• By default CP, but tunable
• Agent runs as a sidecar, connects to server cluster
• Web based UI

Spring Cloud Consul Config

• Uses consul Key/Value (K/V) HTTP API to store hierarchical properties
• Mimics Spring Cloud Config Server loading order

Spring Cloud Consul Discovery

• Full blown consul discovery service implementation
• HTTP API and DNS interface
• Rich health check system (HTTP, TCP or anything)

Spring Cloud Consul Bus

• Uses Consul Event HTTP API
• Non-persistent control plane messages
• Uses Spring Integration

Spring Cloud Consul

• Polyglot
• All-in-one (Discovery, config, bus, cluster)
  • localhost:8500
• Legacy support via DNS

DEMO

CoreOS Etcd

• Incubator Project
  (Not part of a release, yet)
• Distributed key/value store
• CP in CAP
• nice cli and HTTP API
• Many language bindings

Spring Cloud Etcd Config

• Uses etcd Key/Value (K/V) HTTP API to store hierarchical properties
• Mimics Spring Cloud Config Server loading order

Spring Cloud Etcd Discovery

• Bespoke implementation
  • creates value with TTL
• Uses HTTP API
• Spring @Scheduled heartbeat resets TTL

DEMO

Spring Cloud Lattice Discovery

• http://lattice.cf
• Single tenant cloudfoundry--
• Read Only
  • Lattice does registration
• Uses CF Diego Receptor API
• Connectors for: redis, mysql & rabbitmq

Spring Cloud Cluster

• Brixton
• Distributed Locks
• Leader election

Spring Cloud Cluster

• Hazelcast
• Redis
• Zookeeper
• Future: Consul
• Future: Etcd

Questions

@spencerbgibb sgibb@pivotal.io

http://spencer.gibb.us/preso

• Simplicity Itself: Service Discovery Overview
• Knewton: Eureka vs Zookeeper
• Stackshare: Service Discovery Comparison
• Consul.io vs Zookeeper
• Tech. Conversations: Zookeeper vs etcd vs Consul
• https://zookeeper.apache.org
• https://coreos.com/etcd