Skip to content

Instantly share code, notes, and snippets.

What would you like to do?
Ec2 list in go
package main
import (
func check(e error) {
if e != nil {
printIds accepts an aws credentials file and a region, and prints out all
instances within the region in a format that's acceptable to us. Currently that
format is like this:
instance_id name private_ip instance_type public_ip account
Any values that aren't available (such as public ip) will be printed out as
Because the "name" parameter is user-defined, we'll run QueryEscape on it so that
our output stays as a space-separated line.
func printIds(creds aws.CredentialsProvider, account string, region string, wg *sync.WaitGroup) {
defer wg.Done()
svc := ec2.New(&aws.Config{
Credentials: creds,
Region: region,
// Here we create an input that will filter any instances that aren't either
// of these two states. This is generally what we want
params := &ec2.DescribeInstancesInput{
Filters: []*ec2.Filter{
Name: aws.String("instance-state-name"),
Values: []*string{
// TODO: Actually care if we can't connect to a host
resp, _ := svc.DescribeInstances(params)
// if err != nil {
// panic(err)
// }
// Loop through the instances. They don't always have a name-tag so set it
// to None if we can't find anything.
for idx, _ := range resp.Reservations {
for _, inst := range resp.Reservations[idx].Instances {
// We need to see if the Name is one of the tags. It's not always
// present and not required in Ec2.
name := "None"
for _, keys := range inst.Tags {
if *keys.Key == "Name" {
name = url.QueryEscape(*keys.Value)
important_vals := []*string{
// Convert any nil value to a printable string in case it doesn't
// doesn't exist, which is the case with certain values
output_vals := []string{}
for _, val := range important_vals {
if val != nil {
output_vals = append(output_vals, *val)
} else {
output_vals = append(output_vals, "None")
// The values that we care about, in the order we want to print them
fmt.Println(strings.Join(output_vals, " "))
func main() {
// Go for it!
// Make sure the config file exists
config := os.Getenv("HOME") + "/.aws/config"
if _, err := os.Stat(config); os.IsNotExist(err) {
fmt.Println("No config file found at: %s", config)
var wg sync.WaitGroup
file, err := ini.LoadFile(config)
for key, values := range file {
profile := strings.Fields(key)
// Don't print the default or non-standard profiles
if len(profile) != 2 {
// Where to find this host. The account isn't necessary for the creds
// but it's something we expose to users when we print
account := profile[1]
key := values["aws_access_key_id"]
pass := values["aws_secret_access_key"]
creds := aws.Creds(key, pass, "")
// Gather a list of all available AWS regions. Even though we're gathering
// all regions, we still must use a region here for api calls.
svc := ec2.New(&aws.Config{
Credentials: creds,
Region: "us-west-1",
// Iterate over every single stinking region to get a list of available
// ec2 instances
regions, err := svc.DescribeRegions(&ec2.DescribeRegionsInput{})
for _, region := range regions.Regions {
go printIds(creds, account, *region.RegionName, &wg)
// Allow the goroutines to finish printing
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment