Golang : Setting up/configure AWS credentials with official aws-sdk-go

Problem :

You need to setup credentials with official AWS SDK and you have couple of questions :

How to read from ~/.aws/credential file?

How to read from environment variables?

How to use the aws_access_key_id and aws_secret_access_key inside your code instead from environment variables or file?

Solutions :

Read from ~/.aws/credential file example :

 package main

 import (
 "fmt"
 "github.com/aws/aws-sdk-go/aws"
 "github.com/aws/aws-sdk-go/aws/credentials"
 "github.com/aws/aws-sdk-go/service/ec2"
 "os"
 )

 func main() {

 // if you have ~/.aws/credentials file, the SDK will find and use the file automagically
 // see http://blogs.aws.amazon.com/security/post/Tx3D6U6WSFGOK2H/A-New-and-Standardized-Way-to-Manage-Credentials-in-the-AWS-SDKs
 // err... as of May 22nd 2015, it doesn't work for Golang :(
 // therefore, you still have to manually tell it where to find and load which profile

 // the file location and load default profile
 creds := credentials.NewSharedCredentials("/Users/sweetlogic/.aws/credentials", "default")

 credValue, err := creds.Get()

 if err != nil {
 fmt.Println(err)
 os.Exit(1)
 }

 fmt.Println("Value of credentials : ", credValue)

 fmt.Println("----------------------------------------------")

 fmt.Println("Raw credentials : ", creds)

 // test if the credentials configuration works or not

 ec2client := ec2.New(&aws.Config{
 Region: "us-west-2", // get from your AWS console, click "Properties"
 Credentials: creds,
 LogLevel: 1,
 })

 // Call the DescribeInstances Operation
 resp, err := ec2client.DescribeInstances(nil)
 if err != nil {
 panic(err)
 }

 // resp has all of the response data, pull out instance IDs:
 fmt.Println("> Number of reservation sets: ", len(resp.Reservations))
 for idx, res := range resp.Reservations {
 fmt.Println("  > Number of instances: ", len(res.Instances))
 for _, inst := range resp.Reservations[idx].Instances {
 fmt.Println(" - Instance ID: ", *inst.InstanceID)
 }
 }

 }

Read from environment variable example :

 package main

 import (
 "fmt"
 "github.com/aws/aws-sdk-go/aws"
 "github.com/aws/aws-sdk-go/aws/credentials"
 "github.com/aws/aws-sdk-go/service/ec2"
 "os"
 )

 func main() {

 // grab from the environment variables.
 // environment variables names must be uppercase?
 // export AWS_ACCESS_KEY_ID=your access key id
 // export AWS_SECRET_ACCESS_KEY=your secret key


 creds := credentials.NewEnvCredentials()

 credValue, err := creds.Get()

 if err != nil {
 fmt.Println(err)
 os.Exit(1)
 }

 fmt.Println("Value of credentials : ", credValue)

 fmt.Println("----------------------------------------------")

 fmt.Println("Raw credentials : ", creds)

 // test if the credentials configuration works or not

 ec2client := ec2.New(&aws.Config{
 Region: "us-west-2", // get from your AWS console, click "Properties"
 Credentials: creds,
 LogLevel: 1,
 })

 // Call the DescribeInstances Operation
 resp, err := ec2client.DescribeInstances(nil)
 if err != nil {
 panic(err)
 }

 // resp has all of the response data, pull out instance IDs:
 fmt.Println("> Number of reservation sets: ", len(resp.Reservations))
 for idx, res := range resp.Reservations {
 fmt.Println("  > Number of instances: ", len(res.Instances))
 for _, inst := range resp.Reservations[idx].Instances {
 fmt.Println(" - Instance ID: ", *inst.InstanceID)
 }
 }

 }

Read from code example :

 package main

 import (
 "fmt"
 "github.com/aws/aws-sdk-go/aws"
 "github.com/aws/aws-sdk-go/aws/credentials"
 "github.com/aws/aws-sdk-go/service/ec2"
 "os"
 )

 func main() {

 aws_access_key_id := "your access key id"
 aws_secret_access_key := "your secret key"

 // If you're working with temporary security credentials,
 // you can also keep the session token in AWS_SESSION_TOKEN.

 token := ""

 creds := credentials.NewStaticCredentials(aws_access_key_id, aws_secret_access_key, token)
 v, err := creds.Get()

 if err != nil {
 fmt.Println(err)
 os.Exit(1)
 }

 fmt.Println("Value of credentials : ", v)

 fmt.Println("----------------------------------------------")

 fmt.Println("Raw credentials : ", creds)

 ec2client := ec2.New(&aws.Config{
 Region: "us-west-2", // get from your AWS console, click "Properties"
 Credentials: creds,
 LogLevel: 1,
 })

 // Call the DescribeInstances Operation
 resp, err := ec2client.DescribeInstances(nil)
 if err != nil {
 panic(err)
 }

 // resp has all of the response data, pull out instance IDs:
 fmt.Println("> Number of reservation sets: ", len(resp.Reservations))
 for idx, res := range resp.Reservations {
 fmt.Println("  > Number of instances: ", len(res.Instances))
 for _, inst := range resp.Reservations[idx].Instances {
 fmt.Println(" - Instance ID: ", *inst.InstanceID)
 }
 }

 }

NOTE : AWS Golang SDK is still undergoing radical changes by the time of writing and there are possibilities that these examples might be obsolete in future. Till then happy coding!

References :

http://godoc.org/github.com/aws/aws-sdk-go/aws/credentials#NewEnvCredentials

http://godoc.org/github.com/aws/aws-sdk-go/aws/credentials#NewSharedCredentials

http://godoc.org/github.com/aws/aws-sdk-go/aws/credentials#NewStaticCredentials