Rapid API Development in Go

The Go programming language is a statically typed, compiled programming language designed at Google that was released in 2009. It grew quickly in popularity - holding a top 5 position in the most loved programming languages in the Stack Overflow developer survey for 5 consecutive years, and in 2018 was the fastest growing language on GitHub.

Much of Go's popularity can easily be attributed to it's clear and concise syntax, simple concurrency model, strong built-in tooling, and its ability to be easily compiled into a single statically linked binary. However, to me Go's greatest strength is its robust, "batteries included" standard library, which allows developers to rapidly build production ready applications with little to no external dependencies.

In this talk I will provide a brief overview of the Go programming language, and demonstrate how Go can be utilised to rapidly build production ready APIs with just the standard library - HTTP(S) server and all. Finally I will provide a brief demo of a simple API workflow, and talk about some small libraries and tools that can be used to improve the development process and general quality of life.

Transcript

1. Rapid API
   Development in Go
   Josh Michielsen
   

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2. About Me
   → Snr Software Engineer, Platform
   Engineering @ Condé Nast
   (@condenasteng)
   → K8s, AWS, Go
   → Cyclist
   → Photographer
   → Dog Lover!
   @jmickey_
   jmichielsen
   jmickey
   mickey.dev
   j@mickey.dev
   

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4. Third Party Libraries
   A look at some popular 3rd party libraries
   that make API development easier.
   Conclusion
   What Makes Go Unique?
   Briefly explore what makes Go different
   from other languages.
   Language Introduction
   A quick dive into the basics of the Go
   Programming Language.
   Web & APIs in Go
   Jumping right into some code, I will demo
   how to utilise the Go standard library to
   create a simple web server and API.
   01
   AGENDA
   02
   03
   05
   04
   

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5. What Makes Go Unique
   01
   

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6. Features
   → Clear and concise syntax
   → Simple concurrency model
   → Strong built-in tooling
   → Compiled into a single statically linked
   binary
   → Robust standard library
   → Faster than Python
   
   

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7. Projects That Use Go
   → Kubernetes
   → Hashicorp Toolkit
   → Prometheus
   → Docker
   

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8. Language Introduction
   02
   

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9. package main
   import "fmt"
   func main() {
   friend := "DDD East Anglia"
   fmt.Printf("Hello, %s", friend)
   }
   Package declaration. Main
   pkg produces a binary.
   Import statements.
   Function declaration. Main
   pkg must have function main.
   Variable. Will infer the type
   based on the right side of :=.
   Print a string using the
   ‘fmt’ package.
   

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10. Some Examples → Lets jump into VS Code and “go” though some
    examples. Links to these code samples and other are
    provided at the end of the slide deck.
    

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11. Concurrency → “Goroutines” are lightweight threads that provide a
    simple concurrency primitive.
    → “Channels” allow for communication between
    Goroutines.
    → Goroutines are launched using the go keyword.
    

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12. package main
    import (
    "fmt"
    "time"
    )
    func say(s string) {
    for i := 0; i < 5; i++ {
    time.Sleep(100 * time.Millisecond)
    fmt.Println(s)
    }
    }
    func main() {
    go say("world")
    say("hello")
    }
    world
    hello
    hello
    world
    world
    hello
    hello
    world
    world
    hello
    Via ‘A Tour of Go’ - https://tour.golang.org/concurrency/1
    Goroutines
    

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13. package main
    import "fmt"
    func main() {
    messages := make(chan string)
    go func() { messages <- "ping" }
    msg := <-messages
    fmt.Println(msg)
    }
    Channels
    Via ‘Go by Example’ - https://gobyexample.com/channels
    Make a channel. Channels
    are typed.
    The <- operator sends the
    string to the channel.
    Receive from the channel
    and assign to a variable.
    

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14. Compilation → Go compiles code into a single binary.
    → Binaries can be statically linked.
    → Cross-platform compilation is built-in.
    → Supports various architectures.
    CGO_ENABLED=0 go build
    GOOS=windows go build
    GOARCH=arm go build
    http://bit.ly/go-build-values
    

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15. Web & APIs
    03
    

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16. Examples → Simple Web Server
    → JSON Response
    → Middleware
    → Dynamic Routing
    → Gorilla Mux 3rd Party Library
    Link to the repo with the examples is provided at on the
    final slide of the presentation.
    

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17. Third Party
    Libraries
    05
    

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18. Gorilla Toolkit → Toolkit of libraries that simplify web application and
    API development. https://www.gorillatoolkit.org/
    HttpRouter → Performant & light HTTP router with QoL
    improvements over net/http.
    https://github.com/julienschmidt/httprouter
    Go Kit
    Micro → Another popular microservices “runtime”.
    https://github.com/micro/micro
    → Popular microservices framework.
    https://github.com/go-kit/kit
    

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19. Conclusion
    06
    

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20. → Go is a fast, powerful language that provides a simple
    and concise syntax.
    → Web development and API development is possible with
    nothing but the standard library.
    → Cross-platform compilation allows you to run your
    applications almost anywhere.
    → Most 3rd party libraries simply add a nicer UX over the
    standard HTTP implementation.
    

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21. VSCode Go Plugin → Great Visual Studio Code Go plugin.
    https://marketplace.visualstudio.com/items?itemNa
    me=ms-vscode.Go
    Go by Example → Fantastic Go language tutorial with annotated code
    samples. https://gobyexample.com/
    Go in Action
    How to Write Go Code → Getting started guide by the language
    developers/designers.
    https://golang.org/doc/code.html
    → Highly coveted Go book.
    https://www.manning.com/books/go-in-action
    

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22. http://bit.ly/go-samples
    Thanks for Listening!
    @jmickey_
    jmichielsen
    jmickey
    mickey.dev
    j@mickey.dev
    

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