Introduction to Spring Cloud - S1P 2020

Spring Cloud provides tools for developers to quickly build and deploy cloud native apps using common patterns in distributed systems, such as distributed configuration, client-side load-balancers, circuit breakers, API gateway, and service discovery. In this session, we’ll showcase the various Spring Cloud projects and how they overcome various distributed systems challenges like network errors, topology changes, API management, and more. We’ll also show how to start your own projects using the different Spring Cloud modules.

Transcript

1. Introduction to
   Spring Cloud
   Slack: #session-introduction-to-spring-cloud
   Olga Maciaszek-Sharma @olga_maciaszek
   Spencer Gibb @spencerbgibb
   

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2. Safe Harbor Statement
   The following is intended to outline the general direction of VMware's offerings. It is intended for
   information purposes only and may not be incorporated into any contract. Any information regarding
   pre-release of VMware offerings, future updates or other planned modifications is subject to ongoing
   evaluation by VMware and is subject to change. This information is provided without warranty or any kind,
   express or implied, and is not a commitment to deliver any material, code, or functionality, and should not
   be relied upon in making purchasing decisions regarding VMware's offerings. These purchasing decisions
   should only be based on features currently available. The development, release, and timing of any features
   or functionality described for VMware's offerings in this presentation remain at the sole discretion of
   VMware. VMware has no obligation to update forward looking information in this presentation.
   

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3. Agenda
   • Cloud Native
   • Sample Architecture
   • Spring Cloud Components
   • Revisit Sample Architecture
   • Demo
   3
   
   

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4. Cloud Native
   • Distributed
   • Scalable
   • Resilient
   • Automated
   • Organizational (Conway’s Law)
   • Replaceable
   4
   
   

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5. Fallacies of Distributed Computing
   • The network is reliable.
   • Latency is zero.
   • Bandwidth is infinite.
   • The network is secure.
   • Topology doesn't change.
   • There is one administrator.
   • Transport cost is zero.
   • The network is homogeneous.
   https://web.archive.org/web/20071223073932/http://java.sys-con.com/read/38665.htm 5
   
   

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6. 12 Factor Apps https://12factor.net
   1.Code in VCS
   2.Dependencies
   3.Config in environment
   4.Backing Services
   5.Build, release, run
   6.Process
   6
   
   7.Port binding
   8.Concurrency
   9.Disposability
   10.Dev/prod parity
   11.Logs
   12.Admin processes
   See also the 1 Factor App and 15 Factor Apps
   

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7. User Service
   Sample Architecture
   API Gateway Metrics
   Service
   Discovery
   Fraud
   Verifier
   Configuration
   Card Application
   Service
   

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8. Distributed Configuration
   Service
   A
   Config Server
   Service
   B
   

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9. Spring Cloud Config Server
   ● Pluggable
   ○ Git
   ○ Vault
   ○ Credhub
   ○ JDBC
   ○ IaaS resource (S3, etc…)
   ● Retry
   ● Spring Boot compatible client
   9
   

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10. Spring Cloud Consul Config
    ● Bring your own Consul
    ● Uses key-value store
    ● Can be on value per key or a file per key
    ● Can be auto-refreshed
    ● Spring Boot compatible client
    1
    0
    

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11. Others
    ● Spring Cloud Vault
    ● Spring Cloud Zookeeper Config
    ● Direct to IaaS
    ○ Spring Cloud Alibaba
    ○ Spring Cloud AWS
    ○ Spring Cloud Azure
    ○ Spring Cloud GCP
    ● Platform
    ○ K8s config maps
    1
    1
    

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12. Service
    A
    Service
    A
    Service Registration and Discovery
    Service
    A
    Service
    Registry
    Service
    B
    1. Registers 2. Query for Service A instances
    3. Connect
    

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13. Netflix Eureka
    ● Provided by Spring Cloud Netflix
    ● Highly Available
    ● Eventually Consistent
    ● Netflix uses Spring Cloud Netflix!
    http://techblog.netflix.com/2012/09/eureka.html
    1
    3
    

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14. Consul by Hashicorp
    ● Integration by Spring Cloud Consul
    ● Bring your own Consul Servers
    ● Can be strongly consistent
    ● Uses Services API
    ● Supports consul health checks
    ● Spring Boot compatible client
    1
    4
    

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15. Others
    ● Spring Cloud Zookeeper Discovery
    ● Spring Cloud Alibaba (Nacos)
    1
    5
    

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16. Client Side Load-balancer
    Service
    A
    Service
    A
    Service
    A
    Service
    Registry
    Service
    B
    1. Query service A
    instances 2. Select the service A instance to
    send the request to
    Service
    A
    Service
    A
    Service
    A
    

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17. Spring Cloud LoadBalancer
    ● Replaces Netflix Ribbon
    ● Pluggable algorithm
    ● Reactive support
    ● Extensible configuration
    1
    7
    

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18. Failure Mitigation
    

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19. Spring Cloud Circuit Breaker
    ● Protects from cascading failures
    ● Fallback
    ● Pluggable
    ○ Resilience4j
    ○ Spring Retry
    ○ Spring Cloud Alibaba (Sentinel)
    ● Pluggable algorithm
    ● Reactive support
    1
    9
    Open
    Closed
    Half
    Open
    Failure
    threshold
    exceeded
    Success
    Timeout
    Reset
    Failure
    

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20. Retry
    ● Retry failed requests
    ● Spring Retry
    ● Project Reactor
    ● Resilience4j
    2
    0
    

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21. Distributed Tracing
    Browser
    API Gateway
    User
    Service
    Mobile
    App
    Cart
    Service
    Inventory
    Service
    Inventory
    DB
    User
    DB
    

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22. Spring Cloud Sleuth
    ● Trouble-shooting across a distributed system
    ● Instruments for tracing
    ○ Spring Framework
    ○ Spring Boot
    ○ Spring Cloud
    2
    2
    

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23. API Gateway
    Browser
    API Gateway
    User
    Service
    Mobile
    App
    Cart
    Service
    

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24. Spring Cloud Gateway
    ● API Gateway
    ● Spring Boot App
    ● Focus on developer experience and customization
    ● Supports Spring Cloud
    ○ Configuration
    ○ Service Discovery
    ○ LoadBalancer
    ○ Retry/Circuit Breaker
    ○ Rate Limiting
    ○ Sleuth
    2
    4
    

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25. User Service
    (SC Circuit
    Breaker)
    Sample Architecture with Spring Cloud
    Spring Cloud
    Gateway
    (SC CircuitBreaker,
    Retry)
    Metrics
    Eureka
    Service
    Discovery
    Fraud
    Verifier
    Spring Cloud
    Config Server
    Card Application
    Service
    (SC LoadBalancer)
    

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26. Demo
    

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27. What we did not talk about.
    

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28. More to Spring Cloud
    ● Spring Cloud Bus
    ● Spring Cloud OpenFeign
    ● Spring Cloud Contract
    ● Spring Cloud Function
    ● Spring Cloud Stream
    ● Spring Cloud Task
    ● Spring Cloud Data Flow
    ● ...
    2
    8
    

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29. Stay Connected.
    Slack: #session-introduction-to-spring-cloud
    https://github.com/spring-cloud-samples/spring-cloud-intro-demo
    https://github.com/spring-cloud
    https://spring.io/projects/spring-cloud
    Olga Maciaszek-Sharma @olga_maciaszek
    Spencer Gibb @spencerbgibb
    #springone
    @s1p
    

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