cephfs/admin: API for quiesceing io on a cephfs

cephfs has new quiesce feature for cephfs volume. This change add the
feature to go-ceph.

Signed-off-by: Manish <myathnal@redhat.com>

cephfs/admin/fs_quiesce.go

@@ -0,0 +1,135 @@
+//go:build ceph_preview
+
+package admin
+
+import "fmt"
+
+// fixedPointFloat is a custom type that implements the MarshalJSON interface.
+// This is used to format float64 values to two decimal places.
+// By default these get converted to integers in the JSON output and
+// fail the command.
+type fixedPointFloat float64
+
+// MarshalJSON provides a custom implementation for the JSON marshalling
+// of fixedPointFloat. It formats the float to two decimal places.
+func (fpf fixedPointFloat) MarshalJSON() ([]byte, error) {
+	return []byte(fmt.Sprintf("%.2f", float64(fpf))), nil
+}
+
+// fSQuiesceFields is the internal type used to create JSON for ceph.
+// See FSQuiesceOptions for the type that users of the library
+// interact with.
+type fSQuiesceFields struct {
+	Prefix     string          `json:"prefix"`
+	VolName    string          `json:"vol_name"`
+	GroupName  string          `json:"group_name,omitempty"`
+	Members    []string        `json:"members,omitempty"`
+	SetId      string          `json:"set_id,omitempty"`
+	Timeout    fixedPointFloat `json:"timeout,omitempty"`
+	Expiration fixedPointFloat `json:"expiration,omitempty"`
+	AwaitFor   fixedPointFloat `json:"await_for,omitempty"`
+	Await      bool            `json:"await,omitempty"`
+	IfVersion  int             `json:"if_version,omitempty"`
+	Include    bool            `json:"include,omitempty"`
+	Exclude    bool            `json:"exclude,omitempty"`
+	Reset      bool            `json:"reset,omitempty"`
+	Release    bool            `json:"release,omitempty"`
+	Query      bool            `json:"query,omitempty"`
+	All        bool            `json:"all,omitempty"`
+	Cancel     bool            `json:"cancel,omitempty"`
+}
+
+// FSQuiesceOptions are used to specify optional, non-identifying, values
+// to be used when quiescing a cephfs volume.
+type FSQuiesceOptions struct {
+	Timeout    float64
+	Expiration float64
+	AwaitFor   float64
+	Await      bool
+	IfVersion  int
+	Include    bool
+	Exclude    bool
+	Reset      bool
+	Release    bool
+	Query      bool
+	All        bool
+	Cancel     bool
+}
+
+// toFields is used to convert the FSQuiesceOptions to the internal
+// fSQuiesceFields type.
+func (o *FSQuiesceOptions) toFields(volume, group string, subvolumes []string, setId string) *fSQuiesceFields {
+	return &fSQuiesceFields{
+		Prefix:     "fs quiesce",
+		VolName:    volume,
+		GroupName:  group,
+		Members:    subvolumes,
+		SetId:      setId,
+		Timeout:    fixedPointFloat(o.Timeout),
+		Expiration: fixedPointFloat(o.Expiration),
+		AwaitFor:   fixedPointFloat(o.AwaitFor),
+		Await:      o.Await,
+		IfVersion:  o.IfVersion,
+		Include:    o.Include,
+		Exclude:    o.Exclude,
+		Reset:      o.Reset,
+		Release:    o.Release,
+		Query:      o.Query,
+		All:        o.All,
+		Cancel:     o.Cancel,
+	}
+}
+
+// QuiesceState is used to report the state of a quiesced fs volume.
+type QuiesceState struct {
+	Name string  `json:"name"`
+	Age  float64 `json:"age"`
+}
+
+// QuiesceInfoMember is used to report the state of a quiesced fs volume.
+// This is part of sets members object array in the json.
+type QuiesceInfoMember struct {
+	Excluded bool         `json:"excluded"`
+	State    QuiesceState `json:"state"`
+}
+
+// QuiesceInfo reports various informational values about a quiesced volume.
+// This is returned as sets object array in the json.
+type QuiesceInfo struct {
+	Version    int                          `json:"version"`
+	AgeRef     float64                      `json:"age_ref"`
+	State      QuiesceState                 `json:"state"`
+	Timeout    float64                      `json:"timeout"`
+	Expiration float64                      `json:"expiration"`
+	Members    map[string]QuiesceInfoMember `json:"members"`
+}
+
+// FSQuiesceInfo reports various informational values about quiesced volumes.
+type FSQuiesceInfo struct {
+	Epoch      int                    `json:"epoch"`
+	SetVersion int                    `json:"set_version"`
+	Sets       map[string]QuiesceInfo `json:"sets"`
+}
+
+// parseFSQuiesceInfo is used to parse the response from the quiesce command. It returns a FSQuiesceInfo object.
+func parseFSQuiesceInfo(res response) (*FSQuiesceInfo, error) {
+	var info FSQuiesceInfo
+	if err := res.NoStatus().Unmarshal(&info).End(); err != nil {
+		return nil, err
+	}
+	return &info, nil
+}
+
+// FSQuiesce will quiesce the specified subvolumes in a volume.
+// Quiescing a fs will prevent new writes to the subvolumes.
+// Similar To:
+//
+// ceph fs quiesce <volume>
+func (fsa *FSAdmin) FSQuiesce(volume, group string, subvolumes []string, setId string, o *FSQuiesceOptions) (*FSQuiesceInfo, error) {
+	if o == nil {
+		o = &FSQuiesceOptions{}
+	}
+	f := o.toFields(volume, group, subvolumes, setId)
+
+	return parseFSQuiesceInfo(fsa.marshalMgrCommand(f))
+}

cephfs/admin/fs_quiesce_reef_test.go

@@ -0,0 +1,25 @@
+//go:build !squid && ceph_preview
+
+package admin
+
+import (
+	"errors"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestFSQuiesce(t *testing.T) {
+	fsa := getFSAdmin(t)
+	volume := "cephfs"
+	group := NoGroup
+	fsa.CreateSubVolume(volume, group, "quiesceMe", nil)
+	defer func() {
+		err := fsa.RemoveSubVolume(volume, group, "quiesceMe")
+		assert.NoError(t, err)
+	}()
+	ret, err := fsa.FSQuiesce(volume, group, []string{"quiesceMe"}, "", nil)
+	assert.Nil(t, ret)
+	var notImplemented NotImplementedError
+	assert.True(t, errors.As(err, &notImplemented))
+}

cephfs/admin/fs_quiesce_test.go

@@ -0,0 +1,51 @@
+//go:build ceph_preview && squid
+
+package admin
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestFSQuiesce(t *testing.T) {
+	fsa := getFSAdmin(t)
+	volume := "cephfs"
+	group := NoGroup
+	subvol := "quiesceMe"
+	fsa.CreateSubVolume(volume, group, subvol, nil)
+	defer func() {
+		err := fsa.RemoveSubVolume(volume, group, subvol)
+		assert.NoError(t, err)
+	}()
+	ret, err := fsa.FSQuiesce(volume, group, []string{subvol}, "", nil)
+	assert.NoError(t, err)
+	require.NoError(t, err)
+	for _, val := range ret.Sets {
+		assert.Equal(t, 0.0, val.Timeout)
+	}
+	o := &FSQuiesceOptions{}
+	o.Timeout = 10.7
+	ret, err = fsa.FSQuiesce(volume, group, []string{subvol}, "", o)
+	assert.NoError(t, err)
+	for _, val := range ret.Sets {
+		assert.Equal(t, 10.7, val.Timeout)
+	}
+
+	o.Expiration = 15.2
+	ret, err = fsa.FSQuiesce(volume, group, []string{subvol}, "", o)
+	assert.NoError(t, err)
+	for _, val := range ret.Sets {
+		assert.Equal(t, 15.2, val.Expiration)
+		assert.Equal(t, 10.7, val.Timeout)
+	}
+
+	o.Expiration = 15
+	ret, err = fsa.FSQuiesce(volume, group, []string{subvol}, "", o)
+	assert.NoError(t, err)
+	for _, val := range ret.Sets {
+		assert.Equal(t, 15.0, val.Expiration)
+		assert.Equal(t, 10.7, val.Timeout)
+	}
+}

docs/api-status.json

@@ -614,7 +614,14 @@
       }
     ],
     "deprecated_api": [],
-    "preview_api": []
+    "preview_api": [
+      {
+        "name": "FSAdmin.FSQuiesce",
+        "comment": "FSQuiesce will quiesce the specified subvolumes in a volume.\nQuiescing a fs will prevent new writes to the subvolumes.\nSimilar To:\n\nceph fs quiesce <volume>\n",
+        "added_in_version": "$NEXT_RELEASE",
+        "expected_stable_version": "$NEXT_RELEASE_STABLE"
+      }
+    ]
   },
   "rados": {
     "stable_api": [

docs/api-status.md

@@ -8,7 +8,11 @@ No Preview/Deprecated APIs found. All APIs are considered stable.
 
 ## Package: cephfs/admin
 
-No Preview/Deprecated APIs found. All APIs are considered stable.
+### Preview APIs
+
+Name | Added in Version | Expected Stable Version | 
+---- | ---------------- | ----------------------- | 
+FSAdmin.FSQuiesce | $NEXT_RELEASE | $NEXT_RELEASE_STABLE | 
 
 ## Package: rados