16 files changed, 76 insertions, 47 deletions
diff --git a/pkg/credentials/chain.go b/pkg/credentials/chain.go
index 6b0e574..e29826f 100644
--- a/pkg/credentials/chain.go
+++ b/pkg/credentials/chain.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,8 +17,6 @@
 
 package credentials
 
-import "fmt"
-
 // A Chain will search for a provider which returns credentials
 // and cache that provider until Retrieve is called again.
 //
@@ -27,11 +25,11 @@ import "fmt"
 // Providers in the list.
 //
 // If none of the Providers retrieve valid credentials Value, ChainProvider's
-// Retrieve() will return the error, collecting all errors from all providers.
+// Retrieve() will return the no credentials value.
 //
 // If a Provider is found which returns valid credentials Value ChainProvider
 // will cache that Provider for all calls to IsExpired(), until Retrieve is
-// called again.
+// called again after IsExpired() is true.
 //
 //     creds := credentials.NewChainCredentials(
 //         []credentials.Provider{
@@ -58,28 +56,30 @@ func NewChainCredentials(providers []Provider) *Credentials {
 	})
 }
 
-// Retrieve returns the credentials value or error if no provider returned
-// without error.
+// Retrieve returns the credentials value, returns no credentials(anonymous)
+// if no credentials provider returned any value.
 //
-// If a provider is found it will be cached and any calls to IsExpired()
-// will return the expired state of the cached provider.
+// If a provider is found with credentials, it will be cached and any calls
+// to IsExpired() will return the expired state of the cached provider.
 func (c *Chain) Retrieve() (Value, error) {
-	var errs []error
 	for _, p := range c.Providers {
-		creds, err := p.Retrieve()
-		if err != nil {
-			errs = append(errs, err)
+		creds, _ := p.Retrieve()
+		// Always prioritize non-anonymous providers, if any.
+		if creds.AccessKeyID == "" && creds.SecretAccessKey == "" {
 			continue
-		} // Success.
+		}
 		c.curr = p
 		return creds, nil
 	}
-	c.curr = nil
-	return Value{}, fmt.Errorf("No valid providers found %v", errs)
+	// At this point we have exhausted all the providers and
+	// are left without any credentials return anonymous.
+	return Value{
+		SignerType: SignatureAnonymous,
+	}, nil
 }
 
 // IsExpired will returned the expired state of the currently cached provider
-// if there is one.  If there is no current provider, true will be returned.
+// if there is one. If there is no current provider, true will be returned.
 func (c *Chain) IsExpired() bool {
 	if c.curr != nil {
 		return c.curr.IsExpired()
diff --git a/pkg/credentials/chain_test.go b/pkg/credentials/chain_test.go
index cb5a6dd..d26e376 100644
--- a/pkg/credentials/chain_test.go
+++ b/pkg/credentials/chain_test.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -76,7 +76,14 @@ func TestChainGet(t *testing.T) {
 }
 
 func TestChainIsExpired(t *testing.T) {
-	credProvider := &credProvider{expired: true}
+	credProvider := &credProvider{
+		creds: Value{
+			AccessKeyID:     "UXHW",
+			SecretAccessKey: "MYSECRET",
+			SessionToken:    "",
+		},
+		expired: true,
+	}
 	p := &Chain{
 		Providers: []Provider{
 			credProvider,
diff --git a/pkg/credentials/credentials.go b/pkg/credentials/credentials.go
index cc30005..4bfdad4 100644
--- a/pkg/credentials/credentials.go
+++ b/pkg/credentials/credentials.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/pkg/credentials/credentials_test.go b/pkg/credentials/credentials_test.go
index cbfb673..92c77c4 100644
--- a/pkg/credentials/credentials_test.go
+++ b/pkg/credentials/credentials_test.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/pkg/credentials/doc.go b/pkg/credentials/doc.go
index fa1908a..c48784b 100644
--- a/pkg/credentials/doc.go
+++ b/pkg/credentials/doc.go
@@ -1,3 +1,20 @@
+/*
+ * Minio Go Library for Amazon S3 Compatible Cloud Storage
+ * Copyright 2017 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 // Package credentials provides credential retrieval and management
 // for S3 compatible object storage.
 //
diff --git a/pkg/credentials/env_aws.go b/pkg/credentials/env_aws.go
index 1193443..f9b2cc3 100644
--- a/pkg/credentials/env_aws.go
+++ b/pkg/credentials/env_aws.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/pkg/credentials/env_minio.go b/pkg/credentials/env_minio.go
index 791087e..d72e771 100644
--- a/pkg/credentials/env_minio.go
+++ b/pkg/credentials/env_minio.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/pkg/credentials/env_test.go b/pkg/credentials/env_test.go
index 2f72bea..09cd77f 100644
--- a/pkg/credentials/env_test.go
+++ b/pkg/credentials/env_test.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/pkg/credentials/file_aws_credentials.go b/pkg/credentials/file_aws_credentials.go
index 1be6213..5ad6830 100644
--- a/pkg/credentials/file_aws_credentials.go
+++ b/pkg/credentials/file_aws_credentials.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -22,7 +22,7 @@ import (
 	"path/filepath"
 
 	"github.com/go-ini/ini"
-	homedir "github.com/minio/go-homedir"
+	homedir "github.com/mitchellh/go-homedir"
 )
 
 // A FileAWSCredentials retrieves credentials from the current user's home
diff --git a/pkg/credentials/file_minio_client.go b/pkg/credentials/file_minio_client.go
index 9e26dd3..c282c2a 100644
--- a/pkg/credentials/file_minio_client.go
+++ b/pkg/credentials/file_minio_client.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,7 +24,7 @@ import (
 	"path/filepath"
 	"runtime"
 
-	homedir "github.com/minio/go-homedir"
+	homedir "github.com/mitchellh/go-homedir"
 )
 
 // A FileMinioClient retrieves credentials from the current user's home
diff --git a/pkg/credentials/file_test.go b/pkg/credentials/file_test.go
index c62c533..c85c104 100644
--- a/pkg/credentials/file_test.go
+++ b/pkg/credentials/file_test.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/pkg/credentials/iam_aws.go b/pkg/credentials/iam_aws.go
index b862cf5..637df74 100644
--- a/pkg/credentials/iam_aws.go
+++ b/pkg/credentials/iam_aws.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -46,18 +46,6 @@ type IAM struct {
 	endpoint string
 }
 
-// redirectHeaders copies all headers when following a redirect URL.
-// This won't be needed anymore from go 1.8 (https://github.com/golang/go/issues/4800)
-func redirectHeaders(req *http.Request, via []*http.Request) error {
-	if len(via) == 0 {
-		return nil
-	}
-	for key, val := range via[0].Header {
-		req.Header[key] = val
-	}
-	return nil
-}
-
 // IAM Roles for Amazon EC2
 // http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/iam-roles-for-amazon-ec2.html
 const (
@@ -74,8 +62,7 @@ func NewIAM(endpoint string) *Credentials {
 	}
 	p := &IAM{
 		Client: &http.Client{
-			Transport:     http.DefaultTransport,
-			CheckRedirect: redirectHeaders,
+			Transport: http.DefaultTransport,
 		},
 		endpoint: endpoint,
 	}
diff --git a/pkg/credentials/iam_aws_test.go b/pkg/credentials/iam_aws_test.go
index 3e5ad3e..86ea66b 100644
--- a/pkg/credentials/iam_aws_test.go
+++ b/pkg/credentials/iam_aws_test.go
@@ -1,3 +1,20 @@
+/*
+ * Minio Go Library for Amazon S3 Compatible Cloud Storage
+ * Copyright 2017 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 package credentials
 
 import (
diff --git a/pkg/credentials/signature-type.go b/pkg/credentials/signature-type.go
index c64ad6c..1b768e8 100644
--- a/pkg/credentials/signature-type.go
+++ b/pkg/credentials/signature-type.go
@@ -1,5 +1,6 @@
 /*
- * Minio Go Library for Amazon S3 Compatible Cloud Storage (C) 2017 Minio, Inc.
+ * Minio Go Library for Amazon S3 Compatible Cloud Storage
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/pkg/credentials/static.go b/pkg/credentials/static.go
index 25aff56..8b0ba71 100644
--- a/pkg/credentials/static.go
+++ b/pkg/credentials/static.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/pkg/credentials/static_test.go b/pkg/credentials/static_test.go
index 491b155..f1d2d85 100644
--- a/pkg/credentials/static_test.go
+++ b/pkg/credentials/static_test.go
@@ -1,6 +1,6 @@
 /*
  * Minio Go Library for Amazon S3 Compatible Cloud Storage
- * (C) 2017 Minio, Inc.
+ * Copyright 2017 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.