Implement gateway support Google Cloud Storage

vendor/cloud.google.com/go/storage/iam.go

@@ -0,0 +1,108 @@
+// Copyright 2017 Google Inc. All Rights Reserved.
+//
+// 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 storage
+
+import (
+	"cloud.google.com/go/iam"
+	"golang.org/x/net/context"
+	raw "google.golang.org/api/storage/v1"
+	iampb "google.golang.org/genproto/googleapis/iam/v1"
+)
+
+// IAM provides access to IAM access control for the bucket.
+func (b *BucketHandle) IAM() *iam.Handle {
+	return iam.InternalNewHandleClient(&iamClient{raw: b.c.raw}, b.name)
+}
+
+// iamClient implements the iam.client interface.
+type iamClient struct {
+	raw *raw.Service
+}
+
+func (c *iamClient) Get(ctx context.Context, resource string) (*iampb.Policy, error) {
+	req := c.raw.Buckets.GetIamPolicy(resource)
+	setClientHeader(req.Header())
+	var rp *raw.Policy
+	var err error
+	err = runWithRetry(ctx, func() error {
+		rp, err = req.Context(ctx).Do()
+		return err
+	})
+	if err != nil {
+		return nil, err
+	}
+	return iamFromStoragePolicy(rp), nil
+}
+
+func (c *iamClient) Set(ctx context.Context, resource string, p *iampb.Policy) error {
+	rp := iamToStoragePolicy(p)
+	req := c.raw.Buckets.SetIamPolicy(resource, rp)
+	setClientHeader(req.Header())
+	return runWithRetry(ctx, func() error {
+		_, err := req.Context(ctx).Do()
+		return err
+	})
+}
+
+func (c *iamClient) Test(ctx context.Context, resource string, perms []string) ([]string, error) {
+	req := c.raw.Buckets.TestIamPermissions(resource, perms)
+	setClientHeader(req.Header())
+	var res *raw.TestIamPermissionsResponse
+	var err error
+	err = runWithRetry(ctx, func() error {
+		res, err = req.Context(ctx).Do()
+		return err
+	})
+	if err != nil {
+		return nil, err
+	}
+	return res.Permissions, nil
+}
+
+func iamToStoragePolicy(ip *iampb.Policy) *raw.Policy {
+	return &raw.Policy{
+		Bindings: iamToStorageBindings(ip.Bindings),
+		Etag:     string(ip.Etag),
+	}
+}
+
+func iamToStorageBindings(ibs []*iampb.Binding) []*raw.PolicyBindings {
+	var rbs []*raw.PolicyBindings
+	for _, ib := range ibs {
+		rbs = append(rbs, &raw.PolicyBindings{
+			Role:    ib.Role,
+			Members: ib.Members,
+		})
+	}
+	return rbs
+}
+
+func iamFromStoragePolicy(rp *raw.Policy) *iampb.Policy {
+	return &iampb.Policy{
+		Bindings: iamFromStorageBindings(rp.Bindings),
+		Etag:     []byte(rp.Etag),
+	}
+}
+
+func iamFromStorageBindings(rbs []*raw.PolicyBindings) []*iampb.Binding {
+	var ibs []*iampb.Binding
+	for _, rb := range rbs {
+		ibs = append(ibs, &iampb.Binding{
+			Role:    rb.Role,
+			Members: rb.Members,
+		})
+	}
+	return ibs
+}