How to Create a Simple REST Server in Go

Below is an example on how to create a simple REST server in Go.

package main

import (
    "encoding/json"
    "log"
    "net/http"
    "strconv"
)

type Hello struct {
    Message string `json:"message"`
}

func HelloServer(w http.ResponseWriter, req *http.Request) {
    log.Println("Received a request from ", req.RemoteAddr)
    w.Header().Set("Content-Type", "application/json")
    if req.Method == "GET" {
        encoder := json.NewEncoder(w)
        hello := Hello{"Hello World"}
        encoder.Encode(hello)
    }
}

func main() {
    port := 8080
    // serve static content
    http.Handle("/", http.FileServer(http.Dir("html")))
    http.HandleFunc("/hello/", HelloServer)
    log.Println("Starting HTTP server at", port)
    err := http.ListenAndServe(":"+strconv.Itoa(port), nil)
    if err != nil {
        log.Fatal("Unable to start the server: ", err)
    }
}

How to Cross Compile Go Programs

If you download the Go binary for a particular platform, most likely that go binary distribution does not come with support for cross-compiling.

cd myapp
GOOS=windows GOARCH=amd64 go build

go build runtime: windows/amd64 must be bootstrapped using make.bash

In order to add support for cross-compiling in your Go distribution, you need to do the following.

cd $GOROOT/src
GOOS=windows GOARCH=amd64 ./make.bash --no-clean

In this example I am adding cross-compile support to target Windows 64-bit.

cd myapp
GOOS=windows GOARCH=amd64 go build

Now you can easily build Windows 64-bit binaries on a Linux.