API Gateways - Dealing with Distributed Backends

The presentation aims to showcase how API gateways solves the issues associated with distributed back-ends (Microservices and APIs) from a front-end developer's point of view.

Transcript

1. Dealing with Distributed
   Backends using API Gateways
   

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2. About Me
   Software Architecture
   Advocate
   Camera Man @
   Engineers.SG
   Polyglot Developer https://www.pogsdotnet.com
   

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3. Author of API Gateway in a Nutshell
   https://bit.ly/2O4IbAU https://bit.ly/2Dpq44B
   

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4. Free E-Books
   https://www.microsoft.com/net/learn/dotnet/architecture-guides
   

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5. Resources
   

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6. Table of Contents
   I. Abstract
   II. What are API Gateways?
   III. Benefits
   IV. Implementations, Tools and Frameworks
   V. Demo
   VI. Things to Consider
   

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9. Microservices
   

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10. Microservices Pros
    Independent Pieces Independent Teams Independent Releases
    

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11. How a client app communicates with distributed backend APIs.
    Web API
    Ledger
    Web API
    Catalog
    Web API
    Authentication
    

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12. Dealing with Microservice APIs
    as a frontend developer
    is apparently HARD
    

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13. Multiple Point of Contacts
    ????
    ????
    ????
    ????
    Distributed API Challenges
    

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14. Multiple Point of Attacks
    Distributed API Challenges
    

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15. Authentication Issues
    JWT Token A
    JWT Token B
    JWT Token C
    Cookies Against
    N Servers?
    Distributed API Challenges
    

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16. CORS, Domain Name and SSL
    Cross Origin Sharing
    is troublesome
    Buy multiple SSL
    Certificates + Domains?
    Distributed API Challenges
    

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17. Tightly Coupled Client and APIs
    CATALOG
    LEDGER
    CUSTOMERS
    Each team working on
    a bounded context
    will have a hard time
    releasing their changes
    Distributed API Challenges
    

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18. API Gateway
    Web API
    Transactions
    Web API
    Catalog
    Web API
    Users
    API Gateway
    

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19. API Gateway vs Reverse Proxy
    API Gateway
    Reverse Proxy
    Authentication
    Caching
    Rate Limiting Logging Response Aggregation
    

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20. I. Sub-Domain Encapsulation
    II. Single Point of Contact
    III. Faster Cross Continental Communication
    IV. Centralized Authentication
    V. Single CORS, Domain Name and SSL
    VI. Added Layer of Security
    VII. Centralized Cross Cutting Concerns
    BENEFITS OF USING AN API GATEWAY
    

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21. I. Authentication
    II. Logging
    III. Monitoring
    IV. Circuit Breaking
    V. Retries with Jitter
    VI. SSL Termination
    VII. Whitelisting
    VIII. Response Aggregation
    IX. Rate Limiting
    CROSS CUTTING CONCERNS
    

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22. Define Downstream Services
    Downstream services in the context of API gateways are
    independent backend APIs that you want to aggregate and encapsulate.
    

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23. Define Public Endpoints
    Expose Public Endpoints. Public endpoints not exposed on the gateway
    Are considered private which introduces a more secured way of aggregating APIs
    

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24. Define Pipelines Policies
    Pipelines are an ordered list of policies that are executed for requests received from all linked apiEndpoints.
    

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25. Implementation Choices
    CODE
    Generic
    Software
    Cloud
    Management
    Platform
    Code / Config
    Hybrid
    

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26. Azure API
    Management
    AWS API Gateway Kong
    NGINX API Gateway
    Express API Gateway Ocelot API
    Gateway
    Spring Cloud Gateway
    JHipster
    

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27. NOT A SILVER BULLET
    Additional
    Development Cost
    Adds Little
    Communication Latency
    Highly Matured
    Team to Operate
    

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28. Configuration Monolith
    Web API
    Ledger
    Web API
    Catalog
    Web API
    Authentication
    API Gateway
    

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29. Consider Backends for Frontends (BFF)
    Web API
    Ledger
    Web API
    Catalog
    Web API
    Authentication
    API Gateway
    API Gateway
    Desktop Gateway
    Mobile Gateway
    

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30. Question and Answers
    

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31. Resources
    Speaker Deck: https://bit.ly/2FvBzZa
    Github Demo: https://bit.ly/2Q6CNhM
    API Gateway Articles: https://bit.ly/2O4IbAU
    

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