Time how long it takes to determine an s3 bucket's region

Gopkg.lock

# This file is autogenerated, do not edit; changes may be undone by the next 'dep ensure'.


[[projects]]
  name = "github.com/aws/aws-sdk-go"
  packages = [
    "aws",
    "aws/awserr",
    "aws/awsutil",
    "aws/client",
    "aws/client/metadata",
    "aws/corehandlers",
    "aws/credentials",
    "aws/credentials/ec2rolecreds",
    "aws/credentials/endpointcreds",
    "aws/credentials/stscreds",
    "aws/defaults",
    "aws/ec2metadata",
    "aws/endpoints",
    "aws/request",
    "aws/session",
    "aws/signer/v4",
    "internal/sdkio",
    "internal/sdkrand",
    "internal/shareddefaults",
    "private/protocol",
    "private/protocol/query",
    "private/protocol/query/queryutil",
    "private/protocol/rest",
    "private/protocol/restxml",
    "private/protocol/xml/xmlutil",
    "service/s3",
    "service/s3/s3iface",
    "service/s3/s3manager",
    "service/sts"
  ]
  revision = "fad131ddc707880428615dc8bc1587b55fb46d74"
  version = "v1.13.54"

[[projects]]
  name = "github.com/go-ini/ini"
  packages = ["."]
  revision = "6529cf7c58879c08d927016dde4477f18a0634cb"
  version = "v1.36.0"

[[projects]]
  name = "github.com/jmespath/go-jmespath"
  packages = ["."]
  revision = "0b12d6b5"

[solve-meta]
  analyzer-name = "dep"
  analyzer-version = 1
  inputs-digest = "2d724165f4ce7af0fcc09cae7b26a24ddfaa4a65066702b9e7b1b8930c9ab6fc"
  solver-name = "gps-cdcl"
  solver-version = 1

Gopkg.toml

# Gopkg.toml example
#
# Refer to https://github.com/golang/dep/blob/master/docs/Gopkg.toml.md
# for detailed Gopkg.toml documentation.
#
# required = ["github.com/user/thing/cmd/thing"]
# ignored = ["github.com/user/project/pkgX", "bitbucket.org/user/project/pkgA/pkgY"]
#
# [[constraint]]
#   name = "github.com/user/project"
#   version = "1.0.0"
#
# [[constraint]]
#   name = "github.com/user/project2"
#   branch = "dev"
#   source = "github.com/myfork/project2"
#
# [[override]]
#   name = "github.com/x/y"
#   version = "2.4.0"
#
# [prune]
#   non-go = false
#   go-tests = true
#   unused-packages = true


[[constraint]]
  name = "github.com/aws/aws-sdk-go"
  version = "1.13.54"

[prune]
  go-tests = true
  unused-packages = true

main.go

package main

import (
	"context"
	"log"
	"os"
	"time"

	"github.com/aws/aws-sdk-go/aws/endpoints"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/s3/s3manager"
)

func main() {
	if len(os.Args) != 2 {
		log.Fatalf("usage: %s BUCKET\n", os.Args[0])
	}

	s, err := session.NewSession()
	if err != nil {
		log.Fatalf("error creating aws session/cleint: %v\n", err)
	}

	for _, partition := range endpoints.DefaultPartitions() {
		log.Println("Partition:", partition.ID())
		for regionHint := range partition.Regions() {
			log.Println("RegionHint:", regionHint)

			now := time.Now()
			region, err := s3manager.GetBucketRegion(context.Background(), s, os.Args[1], regionHint)
			end := time.Now()
			if err != nil {
				log.Fatalf("error getting bucket region: %v\n", err)
			}

			if region != "" {
				d := end.Sub(now)
				log.Printf("Region: %q, time: %v\n", region, d)
				return
			}
		}
	}
}