Downloads a file and saves it to a given location.

download_example.go

package main

import (
	"fmt"
	"io"
	"net/http"
	"os"
)

// DownloadFile will download a url to a local file.
// Writes file as it downloads and does not load the whole file into memory.
// https://golangcode.com/download-a-file-from-a-url/
func DownloadFile(filepath string, url string) error {
	// Get the data
	response, err := http.Get(url)
	if err != nil {
		return err
	}
	defer response.Body.Close()

	// Create the file
	out, err := os.Create(filepath)
	if err != nil {
		return err
	}
	defer out.Close()

	// Write the body to file
	_, err = io.Copy(out, response.Body)
	return err
}

func main() {
	args := os.Args[1:]
	filename := args[0]
	fileURL := args[1]

	fmt.Printf("Downloading to: %s\nFrom: %s", filename, fileURL)

	if err := DownloadFile(filename, fileURL); err != nil {
		panic(err)
	}
}