Add error instance for better checking

Author: YakDriver

awsauth.go

@@ -29,6 +29,13 @@ const (
 	providing credentials for the AWS Provider`
 )
 
+var (
+	// ErrNoValidCredentialSources indicates that no credentials source could be found
+	ErrNoValidCredentialSources = errNoValidCredentialSources()
+)
+
+func errNoValidCredentialSources() error { return errors.New(errMsgNoValidCredentialSources) }
+
 // GetAccountIDAndPartition gets the account ID and associated partition.
 func GetAccountIDAndPartition(iamconn *iam.IAM, stsconn *sts.STS, authProviderName string) (string, string, error) {
 	var accountID, partition string
@@ -175,7 +182,7 @@ func GetCredentialsFromSession(c *Config) (*awsCredentials.Credentials, error) {
 	if c.Profile == "" {
 		sess, err = session.NewSession()
 		if err != nil {
-			return nil, errors.New(errMsgNoValidCredentialSources)
+			return nil, ErrNoValidCredentialSources
 		}
 	} else {
 		options := &session.Options{
@@ -191,7 +198,7 @@ func GetCredentialsFromSession(c *Config) (*awsCredentials.Credentials, error) {
 		sess, err = session.NewSessionWithOptions(*options)
 		if err != nil {
 			if IsAWSErr(err, "NoCredentialProviders", "") {
-				return nil, errors.New(errMsgNoValidCredentialSources)
+				return nil, ErrNoValidCredentialSources
 			}
 			return nil, fmt.Errorf("Error creating AWS session: %s", err)
 		}
@@ -200,7 +207,7 @@ func GetCredentialsFromSession(c *Config) (*awsCredentials.Credentials, error) {
 	creds := sess.Config.Credentials
 	cp, err := sess.Config.Credentials.Get()
 	if err != nil {
-		return nil, errors.New(errMsgNoValidCredentialSources)
+		return nil, ErrNoValidCredentialSources
 	}
 
 	log.Printf("[INFO] Successfully derived credentials from session")

awsauth_test.go

@@ -7,7 +7,6 @@ import (
 	"os"
 	"testing"
 
-	"github.com/aws/aws-sdk-go/aws/awserr"
 	"github.com/aws/aws-sdk-go/aws/credentials/ec2rolecreds"
 	"github.com/aws/aws-sdk-go/service/iam"
 	"github.com/aws/aws-sdk-go/service/sts"
@@ -423,20 +422,12 @@ func TestAWSGetCredentials_shouldErrorWhenBlank(t *testing.T) {
 	defer resetEnv()
 
 	cfg := Config{}
-	c, err := GetCredentials(&cfg)
+	_, err := GetCredentials(&cfg)
 
-	if err != nil {
+	if err != ErrNoValidCredentialSources {
 		t.Fatalf("Unexpected error: %s", err)
 	}
 
-	_, err = c.Get()
-	if awsErr, ok := err.(awserr.Error); ok {
-		if awsErr.Code() != "NoCredentialProviders" {
-			t.Fatal("Expected NoCredentialProviders error")
-		}
-	} else {
-		t.Fatal("Expected AWS error")
-	}
 	if err == nil {
 		t.Fatal("Expected an error given empty env, keys, and IAM in AWS Config")
 	}
@@ -586,22 +577,14 @@ func TestAWSGetCredentials_shouldErrorWithInvalidEndpoint(t *testing.T) {
 	ts := invalidAwsEnv(t)
 	defer ts()
 
-	creds, err := GetCredentials(&Config{})
-	if err != nil {
+	_, err := GetCredentials(&Config{})
+	if err != ErrNoValidCredentialSources {
 		t.Fatalf("Error gettings creds: %s", err)
 	}
-	if creds == nil {
-		t.Fatal("Expected a static creds provider to be returned")
-	}
 
-	v, err := creds.Get()
 	if err == nil {
 		t.Fatal("Expected error returned when getting creds w/ invalid EC2 endpoint")
 	}
-
-	if v.ProviderName != "" {
-		t.Fatalf("Expected provider name to be empty, %q given", v.ProviderName)
-	}
 }
 
 func TestAWSGetCredentials_shouldIgnoreInvalidEndpoint(t *testing.T) {

go.mod

@@ -8,3 +8,5 @@ require (
 	golang.org/x/net v0.0.0-20190213061140-3a22650c66bd // indirect
 	golang.org/x/text v0.3.0 // indirect
 )
+
+go 1.13

session.go

@@ -2,7 +2,6 @@ package awsbase
 
 import (
 	"crypto/tls"
-	"errors"
 	"fmt"
 	"log"
 	"net/http"
@@ -63,7 +62,7 @@ func GetSession(c *Config) (*session.Session, error) {
 	sess, err := session.NewSessionWithOptions(*options)
 	if err != nil {
 		if IsAWSErr(err, "NoCredentialProviders", "") {
-			return nil, errors.New(errMsgNoValidCredentialSources)
+			return nil, ErrNoValidCredentialSources
 		}
 		return nil, fmt.Errorf("Error creating AWS session: %s", err)
 	}