swift: If storage_policy isn't set, use the root containers policy

Ensure that if we need to create a segments container it uses the same
storage policy as the root container.

Fixes #8858

backend/swift/swift.go

@@ -561,6 +561,21 @@ func (f *Fs) setRoot(root string) {
 	f.rootContainer, f.rootDirectory = bucket.Split(f.root)
 }
 
+// Fetch the base container's policy to be used if/when we need to create a
+// segments container to ensure we use the same policy.
+func (f *Fs) fetchStoragePolicy(ctx context.Context, container string) (fs.Fs, error) {
+	err := f.pacer.Call(func() (bool, error) {
+		var rxHeaders swift.Headers
+		_, rxHeaders, err := f.c.Container(ctx, container)
+
+		f.opt.StoragePolicy = rxHeaders["X-Storage-Policy"]
+		fs.Debugf(f, "Auto set StoragePolicy to %s", f.opt.StoragePolicy)
+
+		return shouldRetryHeaders(ctx, rxHeaders, err)
+	})
+	return nil, err
+}
+
 // NewFsWithConnection constructs an Fs from the path, container:path
 // and authenticated connection.
 //
@@ -590,6 +605,7 @@ func NewFsWithConnection(ctx context.Context, opt *Options, name, root string, c
 		f.opt.UseSegmentsContainer.Valid = true
 		fs.Debugf(f, "Auto set use_segments_container to %v", f.opt.UseSegmentsContainer.Value)
 	}
+
 	if f.rootContainer != "" && f.rootDirectory != "" {
 		// Check to see if the object exists - ignoring directory markers
 		var info swift.Object
@@ -1132,6 +1148,13 @@ func (f *Fs) newSegmentedUpload(ctx context.Context, dstContainer string, dstPat
 		container:    dstContainer,
 	}
 	if f.opt.UseSegmentsContainer.Value {
+		if f.opt.StoragePolicy == "" {
+			_, err = f.fetchStoragePolicy(ctx, dstContainer)
+			if err != nil {
+				return nil, err
+			}
+		}
+
 		su.container += segmentsContainerSuffix
 		err = f.makeContainer(ctx, su.container)
 		if err != nil {

backend/swift/swift_test.go

@@ -76,6 +76,7 @@ func (f *Fs) testNoChunk(t *testing.T) {
 
 // Additional tests that aren't in the framework
 func (f *Fs) InternalTest(t *testing.T) {
+	t.Run("PolicyDiscovery", f.testPolicyDiscovery)
 	t.Run("NoChunk", f.testNoChunk)
 	t.Run("WithChunk", f.testWithChunk)
 	t.Run("WithChunkFail", f.testWithChunkFail)
@@ -195,4 +196,50 @@ func (f *Fs) testCopyLargeObject(t *testing.T) {
 	require.Equal(t, obj.Size(), objTarget.Size())
 }
 
+func (f *Fs) testPolicyDiscovery(t *testing.T) {
+	ctx := context.TODO()
+	container := "testPolicyDiscovery-1"
+	// Reset the policy so we can test if it is populated.
+	f.opt.StoragePolicy = ""
+	err := f.makeContainer(ctx, container)
+	require.NoError(t, err)
+	_, err = f.fetchStoragePolicy(ctx, container)
+	require.NoError(t, err)
+
+	// Default policy for Swift is Policy-0.
+	assert.Equal(t, "Policy-0", f.opt.StoragePolicy)
+
+	// Create a container using a non-default policy, and check to ensure
+	// that the created segments container uses the same non-default policy.
+	policy := "Policy-1"
+	container = "testPolicyDiscovery-2"
+
+	f.opt.StoragePolicy = policy
+	err = f.makeContainer(ctx, container)
+	require.NoError(t, err)
+
+	// Reset the policy so we can test if it is populated, and set to the
+	// non-default policy.
+	f.opt.StoragePolicy = ""
+	_, err = f.fetchStoragePolicy(ctx, container)
+	require.NoError(t, err)
+	assert.Equal(t, policy, f.opt.StoragePolicy)
+
+	// Test that when a segmented upload container is made, the newly
+	// created container inherits the non-default policy of the base
+	// container.
+	f.opt.StoragePolicy = ""
+	f.opt.UseSegmentsContainer.Value = true
+	su, err := f.newSegmentedUpload(ctx, container, "")
+	require.NoError(t, err)
+	// The container name we expected?
+	segmentsContainer := container + segmentsContainerSuffix
+	assert.Equal(t, segmentsContainer, su.container)
+	// The policy we expected?
+	f.opt.StoragePolicy = ""
+	_, err = f.fetchStoragePolicy(ctx, su.container)
+	require.NoError(t, err)
+	assert.Equal(t, policy, f.opt.StoragePolicy)
+}
+
 var _ fstests.InternalTester = (*Fs)(nil)

fstest/testserver/init.d/TestSwiftAIO

@@ -8,8 +8,10 @@ PORT=28628
 . $(dirname "$0")/docker.bash
 
 start() {
+    # We need to replace the remakerings in the container to create Policy-1.
     docker run --rm -d --name ${NAME} \
            -p 127.0.0.1:${PORT}:8080 \
+	   -v $(dirname "$0")/TestSwiftAIO.d/remakerings:/swift/bin/remakerings:ro \
            bouncestorage/swift-aio
 
     echo type=swift

fstest/testserver/init.d/TestSwiftAIO.d/remakerings

@@ -0,0 +1,33 @@
+#!/bin/bash
+
+cd /etc/swift
+
+if ! grep storage-policy swift.conf; then
+    cat <<EOF >> swift.conf
+
+# Policy-0 is the default, we need two policies to test policy inheritance.
+[storage-policy:0]
+name = Policy-0
+default = true
+
+[storage-policy:1]
+name = Policy-1
+EOF
+fi
+
+rm -f *.builder *.ring.gz backups/*.builder backups/*.ring.gz
+
+swift-ring-builder object.builder create 10 1 1
+swift-ring-builder object.builder add r1z1-127.0.0.1:6010/sdb1 1
+swift-ring-builder object.builder rebalance
+swift-ring-builder container.builder create 10 1 1
+swift-ring-builder container.builder add r1z1-127.0.0.1:6011/sdb1 1
+swift-ring-builder container.builder rebalance
+swift-ring-builder account.builder create 10 1 1
+swift-ring-builder account.builder add r1z1-127.0.0.1:6012/sdb1 1
+swift-ring-builder account.builder rebalance
+
+# For Policy-1:
+swift-ring-builder object-1.builder create 10 1 1
+swift-ring-builder object-1.builder add r1z1-127.0.0.1:6010/sdb1 1
+swift-ring-builder object-1.builder rebalance