X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/625076c05698e37beb732850dc01248be9dbe7f6..a6fd7801f084f280cbf668f8a1f6bf9d9bbd0def:/lib/cloud/ec2/ec2.go

diff --git a/lib/cloud/ec2/ec2.go b/lib/cloud/ec2/ec2.go
index 29062c491e..1e0de74024 100644
--- a/lib/cloud/ec2/ec2.go
+++ b/lib/cloud/ec2/ec2.go
@@ -19,6 +19,8 @@ import (
 	"git.arvados.org/arvados.git/sdk/go/arvados"
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/aws/credentials"
+	"github.com/aws/aws-sdk-go/aws/credentials/ec2rolecreds"
+	"github.com/aws/aws-sdk-go/aws/ec2metadata"
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/ec2"
 	"github.com/sirupsen/logrus"
@@ -65,12 +67,19 @@ func newEC2InstanceSet(config json.RawMessage, instanceSetID cloud.InstanceSetID
 	if err != nil {
 		return nil, err
 	}
-	awsConfig := aws.NewConfig().
-		WithCredentials(credentials.NewStaticCredentials(
-			instanceSet.ec2config.AccessKeyID,
-			instanceSet.ec2config.SecretAccessKey,
-			"")).
-		WithRegion(instanceSet.ec2config.Region)
+
+	sess, err := session.NewSession()
+	if err != nil {
+		return nil, err
+	}
+	// First try any static credentials, fall back to an IAM instance profile/role
+	creds := credentials.NewChainCredentials(
+		[]credentials.Provider{
+			&credentials.StaticProvider{Value: credentials.Value{AccessKeyID: instanceSet.ec2config.AccessKeyID, SecretAccessKey: instanceSet.ec2config.SecretAccessKey}},
+			&ec2rolecreds.EC2RoleProvider{Client: ec2metadata.New(sess)},
+		})
+
+	awsConfig := aws.NewConfig().WithCredentials(creds).WithRegion(instanceSet.ec2config.Region)
 	instanceSet.client = ec2.New(session.Must(session.NewSession(awsConfig)))
 	instanceSet.keys = make(map[string]string)
 	if instanceSet.ec2config.EBSVolumeType == "" {
@@ -103,10 +112,10 @@ func awsKeyFingerprint(pk ssh.PublicKey) (md5fp string, sha1fp string, err error
 	sha1pkix := sha1.Sum([]byte(pkix))
 	md5fp = ""
 	sha1fp = ""
-	for i := 0; i < len(md5pkix); i += 1 {
+	for i := 0; i < len(md5pkix); i++ {
 		md5fp += fmt.Sprintf(":%02x", md5pkix[i])
 	}
-	for i := 0; i < len(sha1pkix); i += 1 {
+	for i := 0; i < len(sha1pkix); i++ {
 		sha1fp += fmt.Sprintf(":%02x", sha1pkix[i])
 	}
 	return md5fp[1:], sha1fp[1:], nil
@@ -251,7 +260,7 @@ func (instanceSet *ec2InstanceSet) Instances(tags cloud.InstanceTags) (instances
 	}
 }
 
-func (az *ec2InstanceSet) Stop() {
+func (instanceSet *ec2InstanceSet) Stop() {
 }
 
 type ec2Instance struct {