GraphQL

A simple introduction to what exactly GraphQL is, how you create your own GraphQL API's, and how it compares to REST API's.

Transcript

1. Tech talk
   

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2. “ GraphQL is a query language for your API, and a
   server-side runtime for executing queries by using a
   type system you define for your data. GraphQL isn't
   tied to any specific database or storage engine and is
   instead backed by your existing code and data. ”
   – Taken from Introduction to GraphQL
   What is GraphQL?
   

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3. What about REST?
   REST GraphQL
   Multiple endpoints Single endpoint
   Fixed response structure(s) Fetch what you need
   No specification Query language
   Separate documentation Documented schema
   HTTP Protocol-agnostic
   

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4. Query language
   

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5. Query language
   +
   

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6. Specification
   GraphQL
   Schema
   Types
   Resolvers
   Mutations
   Query
   Scalars
   Inputs
   

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7. What is a type?
   

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8. What is a query type?
   

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9. What is a mutation type?
   

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10. What is an input type?
    

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11. What are resolvers?
    

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12. What are resolvers?
    

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13. Live coding
    

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14. Silver bullet?
    - N + 1 problem
    - Caching
    - File uploads
    - Security
    

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15. Resources
    - Specification: https://graphql.org/
    - Apollo GraphQL platform: https://www.apollographql.com/
    - Java implementatie: https://www.graphql-java.com/
    - Spring boot starter: https://www.graphql-java-kickstart.com/spring-boot/
    - My blogpost: https://blog.optis.be/exploring-graphql-3de51e39d707
    - Source code: https://github.com/optis/tech-talk-graphql
    

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16. The End
    

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