The document introduces GO and discusses why a consulting firm chose to build an instant messaging server using GO. It provides an overview of GO, including that it is a lightweight programming language developed by Google that uses garbage collection and makes concurrency easy using goroutines and channels. The document also provides code samples and discusses getting started with GO development.

1. Intro to GO
Bangkok GO Meetup 2014

2. English>?
Still learning thai

3. My Level of thai

4. Survey the Audience
● Who a hip language, Ruby / Javascript
● Who uses Java / C#
● Has anyone played with GO?

5. Whats this talk about
● Instant Messenger Server in GO
● Why we chose go
● Basics about go
● How to get started with GO

7. Who am I ?
Small consulting firm Hyperworks
*Built Bloomberg.com
*Real time ad servers
*Ecommerce sites (gucci,reebok etc)
*Thomson Reuters Messenger Client/Server

8. What we’re we using
● Instant Messaging Server / Client
● Backend 100% GO
● 300k user base of financial traders!
● 20 Megabits of sustained traffic

9. Why GO?

11. C++
● Dying
● Hard to hire people
● Nothing new happening
● Not cool

12. Java
● Slow to code
● Very verbose
● Need a much larger team

13. C#
● Hate windows on a server

14. GO
● Lightweight concurrency
● Fast development cycle
● Hip with the kids

15. About GO
●
●
●
●
●
●
Google’s programming language
Garbage collected
Author is Rob Pike (Inventor of unix)
Fast Compilations
Fast Runtime
Easy to learn

16. Go is like C/C#/Java
Hello World (Aka a webserver)
import (
"fmt"
"http"
)
func handler(c *http.Conn, r *http.Request) {
fmt.Fprintf(c, "Hello, %s.n", r.URL.Path[1:])
}
func main() {
http.ListenAndServe(":8080", http.HandlerFunc(handler))
}

17. Lambdas
For javascript/ruby devs
valueToCloseOver := "My name is HAL."
anon := func(s string) string {
return "Hiya, " + name + ". " + valueToCloseOver
}
anotherFunction(anon)

19. Go Routines
● Lightweight threads
● Easy concurrency
● Like Erlang, communicate instead of sharing
memory

20. Channels
● Container for messages between go routines
● Concorrent safe

21. Code samples
c := make(chan int) // Allocate a channel.
// Start the sort in a goroutine; when it completes, signal on the channel.
go func() {
list.Sort()
c <- 1 // Send a signal; value does not matter.
}()
doSomethingForAWhile()
<-c // Wait for sort to finish; discard sent value.

22. No inheritance
● Interfaces over inheritance
● Duck typing
● Composition

23. Example interface code
type Stringer interface {
String() string
}
var value interface{} // Value provided by caller.
switch str := value.(type) {
case string:
return str
case Stringer:
return str.String()
}

25. Things not so good
● Windows support
● Small number of libraries
● Community still small but growing

26. How to get started
● http://play.golang.org/
● http://golang.org/doc/

27. Q/A

28. Thanks!
Btw We’re Hiring !