Intrigued by why some of the world's largest companies (Netflix, Google, Cisco, Twitter, Uber etc) are using gRPC? In this demo based talk we delve into the world of gRPC in .Net, what it does and why we should use it. We compare the interface with both Rest and graphQL. We will show you how to implement grpc server-side in .net and in the web. Finally, I will show you how the tooling helps you deliver powerful interfaces and interact with them quickly and simply.

1. Demystifying gRPC
By John Staveley MVP
23/05/2023
https://uk.linkedin.com/in/johnstaveley/
@johnstaveley

2. Overview
 Who uses it?
 What is it?
 Why use it?
 Basic gRPC method calls in C#
 Tooling in VS
 Streaming
 Using over the web

3. Who uses gRPC?
created in 2015

4. What is gRPC?
 Http2
 Protocol buffers
 Binary formatting
 TLS
 Support for cross cutting concerns such as authentication and error handling
 Good language support: C# / .NET, C++, Dart, Go, Java, Kotlin, Node,
Objective-C, PHP, Python, Ruby, JavaScript

5. Why? gRPC vs
 Both cross platform
 gRPC 7 to 10 times faster than REST
 REST has native browser support, gRPC has support via gRPC-Web
 REST has loose contracts, gRPC has strict contracts
 Json is human readable
 REST is better for massive payloads

6. Both: gRPC and
 Released 2015/2016
 Advantages over Rest
 Interface Definition Language
 Open source
 Publish Single Endpoint

7. Why? gRPC vs
 Transport Agnostic (Mostly http)
 Uses Json
 Can get all data together (easier
to combine method calls)
 Weaker coupling
 One-way streaming
 Caching of Get requests does not
work by default
 Used over Http/2
 Uses Protobuf (Smaller packet
size, faster serialisation)
 Single method at a time
 Stronger coupling
 Two-way streaming

8. How? Getting started with C#
 NuGet packages
 Default project (ASP.NET Core gRPC service)
 Setting up your service project
 The .proto file
 Startup

9. DEMO 1: Hello world Server
 Basic gRPC project
 Greeter service
 Call using postman or grpccurl

10. Protocol buffers
 Interface Definition Language
 Types: bool, string, bytes, float, double, int32, int64, uint32, uint64, sint32,
sint64. Full list here: https://protobuf.dev/programming-
guides/proto3/#scalar
 Other types: import "myproject/other_protos.proto";
 E.g. Timestamp
 Field numbers must be unique!

11. DEMO 2: Client
 Console project
 Install packages
 Add a service reference of type gRPC
 Add client code
 DEMO: Calling new method from client code

12. Extending the basic service
 Timestamp
 Enum
 Reserve keyword
 Optional keyword
 Empty type
 Streaming (1 way / 2 way)
 Authentication
 https://protobuf.dev/reference/csharp/api-docs/

13. Cloud gRPC support
 EC2 and Application Load Balancer
 Azure App Service
 Http = 2.0
 Http 2.0 Proxy = On/gRPC Only
 End to End Encryption = On
 Both support unary and streaming modes

14. Calling from the web
 Server uses grpc-web proxy
 Install-Package grpc.aspnetcore.web
 Web client
 Install Npm packages
 Talk through and execute Generate.ps1
 Talk through send.js

15. In Summary
 gRPC: High speed, well supported
 Good for streaming and polyglot services
 Used on the web via grpc-web proxy
 Well supported with tooling in VS, Postman etc

16. Resources
 https://stackoverflow.blog/2022/11/28/when-to-use-grpc-vs-graphql/
 https://app.pluralsight.com/library/courses/aspdotnet-core-6-using-grpc/
 https://grpc.io/docs/
 Source code: https://github.com/johnstaveley/DataLogger
 Slides: https://www.slideshare.net/johnstaveley/

17. Any Questions?
@johnstaveley
Demo code: https://github.com/johnstaveley/DataLogger/
Slides: https://www.slideshare.net/johnstaveley/
Connect: https://uk.linkedin.com/in/johnstaveley/