This document provides an introduction to GraphQL, including its history and key concepts. It discusses how GraphQL works with queries and mutations, schemas and types, validations and executions. Comparisons are made between GraphQL and REST. Examples of GraphQL queries and schemas are shown. Benefits of GraphQL include minimal code changes, no need for versioning, and handling client-specific data with one endpoint. Disadvantages include lack of "select *" and potential for large argument objects. Major companies using GraphQL are cited.

1. Introduction to GraphQL
Course: Internet Programming Term: Spring-2017 By: Sangeeta Ashrit

2. Agenda
• Introduction toGraphQL
• History of GraphQL
• Queries & Mutations
• Schemas & Types
• Validations & Executions
• Compared toREST
• Demo Examples
• Q&A

3. • Facebook use to have web
framework for mobile apps.
History of GraphQL

4. Facebook Current Native App :
Today, Facebook gets more than260 billion requests/day

5. What isGraphQL?
What is GraphQL ?
• GraphQL is a query language
• Specification for a server to execute queries
What Graph is NOT !
• Its not a database
• Not a library
• Not a storage engine
• Not language specific

6. How GraphQL works?
iOS App
Android App
Web App
Desktop App
GraphQL
Server
Data
Data
GraphQL
Queries
JSON
Payload
1
2

7. GraphQL Query Example

8. Schemas & Types
• Type System
• Type Language
• Enumerations, Lists, Interface creation
• Aliases
• Fragments

9. Schemas & Types Explanation
Type System:

10. Schemas & Types Explanation
Aliases:

11. Schemas & Types Explanation
Fragments:

12. Schemas & Types Explanation
Fragments:
Grace

13. Validations

14. 1.Minimal code changes to adapt
Other Benefits of GraphQL

15. Other Benefits of GraphQL
2.No need to maintain versioning informations

16. Other Benefits of GraphQL

17. REST Vs GraphQL
• Shopify claims : As application grows larger, REST architecture often becomes
unmanageable
• Using REST, over fetching/under fetching of data becomes part of the application
development.
• Handling custom endpoints, multiple end points can be time consuming/costly
effort.

18. Custom
Endpoint 1
Custom
Endpoint2
2
Custom
Endpoint 3
Custom
Endpoint 4
Custom
Endpoint 5
Custom
Endpoint 6
View 1 View 2 View 3 View 4 View 5 View 6
REST: Custom End Points

20. GraphQL:
GraphQL
View 1 View 2 View ‘n’

21. Advantages
• What you see is what you get
• Client specificdata
• Application layerprotocol
• Strong typed
• Self documenting
• Existing backendAPIs
• RFC - http://facebook.github.io/graphql
• Extra powers with Relay and React
• Introspection
• Active community

22. Disadvantages
• No select *
• Args can become enormous
• Boilerplate

23. Who’s Using GraphQL:

24. References:
• http://graphql.org/graphql-js/
• https://facebook.github.io/graphql/
• http://graphql.org/graphql-js/running-an-express-graphql-server/
• https://www.youtube.com/watch?v=WQLzZf34FJ8

25. Thank you!
Questions?
Sangeeta Ashrit
City College of New York
sangeeta2288