/
client_csi_endpoint.go
204 lines (173 loc) · 6.24 KB
/
client_csi_endpoint.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
package nomad
import (
"fmt"
"math/rand"
"strings"
"time"
metrics "github.com/armon/go-metrics"
log "github.com/hashicorp/go-hclog"
memdb "github.com/hashicorp/go-memdb"
cstructs "github.com/hashicorp/nomad/client/structs"
)
// ClientCSI is used to forward RPC requests to the targed Nomad client's
// CSIController endpoint.
type ClientCSI struct {
srv *Server
logger log.Logger
}
func (a *ClientCSI) ControllerAttachVolume(args *cstructs.ClientCSIControllerAttachVolumeRequest, reply *cstructs.ClientCSIControllerAttachVolumeResponse) error {
defer metrics.MeasureSince([]string{"nomad", "client_csi_controller", "attach_volume"}, time.Now())
clientIDs, err := a.clientIDsForController(args.PluginID)
if err != nil {
return fmt.Errorf("controller attach volume: %v", err)
}
for _, clientID := range clientIDs {
args.ControllerNodeID = clientID
state, ok := a.srv.getNodeConn(clientID)
if !ok {
return findNodeConnAndForward(a.srv,
clientID, "ClientCSI.ControllerAttachVolume", args, reply)
}
err = NodeRpc(state.Session, "CSI.ControllerAttachVolume", args, reply)
if err == nil {
return nil
}
if a.isRetryable(err) {
a.logger.Debug("failed to reach controller on client",
"nodeID", clientID, "err", err)
continue
}
return fmt.Errorf("controller attach volume: %v", err)
}
return fmt.Errorf("controller attach volume: %v", err)
}
func (a *ClientCSI) ControllerValidateVolume(args *cstructs.ClientCSIControllerValidateVolumeRequest, reply *cstructs.ClientCSIControllerValidateVolumeResponse) error {
defer metrics.MeasureSince([]string{"nomad", "client_csi_controller", "validate_volume"}, time.Now())
clientIDs, err := a.clientIDsForController(args.PluginID)
if err != nil {
return fmt.Errorf("validate volume: %v", err)
}
for _, clientID := range clientIDs {
args.ControllerNodeID = clientID
state, ok := a.srv.getNodeConn(clientID)
if !ok {
return findNodeConnAndForward(a.srv,
clientID, "ClientCSI.ControllerValidateVolume", args, reply)
}
err = NodeRpc(state.Session, "CSI.ControllerValidateVolume", args, reply)
if err == nil {
return nil
}
if a.isRetryable(err) {
a.logger.Debug("failed to reach controller on client",
"nodeID", clientID, "err", err)
continue
}
return fmt.Errorf("validate volume: %v", err)
}
return fmt.Errorf("validate volume: %v", err)
}
func (a *ClientCSI) ControllerDetachVolume(args *cstructs.ClientCSIControllerDetachVolumeRequest, reply *cstructs.ClientCSIControllerDetachVolumeResponse) error {
defer metrics.MeasureSince([]string{"nomad", "client_csi_controller", "detach_volume"}, time.Now())
clientIDs, err := a.clientIDsForController(args.PluginID)
if err != nil {
return fmt.Errorf("controller detach volume: %v", err)
}
for _, clientID := range clientIDs {
args.ControllerNodeID = clientID
state, ok := a.srv.getNodeConn(clientID)
if !ok {
return findNodeConnAndForward(a.srv,
clientID, "ClientCSI.ControllerDetachVolume", args, reply)
}
err = NodeRpc(state.Session, "CSI.ControllerDetachVolume", args, reply)
if err == nil {
return nil
}
if a.isRetryable(err) {
a.logger.Debug("failed to reach controller on client",
"nodeID", clientID, "err", err)
continue
}
return fmt.Errorf("controller detach volume: %v", err)
}
return fmt.Errorf("controller detach volume: %v", err)
}
// we can retry the same RPC on a different controller in the cases where the
// client has stopped and been GC'd, or where the controller has stopped but
// we don't have the fingerprint update yet
func (a *ClientCSI) isRetryable(err error) bool {
// TODO: msgpack-rpc mangles the error so we lose the wrapping,
// but if that can be fixed upstream we should use that here instead
return strings.Contains(err.Error(), "CSI client error (retryable)") ||
strings.Contains(err.Error(), "Unknown node")
}
func (a *ClientCSI) NodeDetachVolume(args *cstructs.ClientCSINodeDetachVolumeRequest, reply *cstructs.ClientCSINodeDetachVolumeResponse) error {
defer metrics.MeasureSince([]string{"nomad", "client_csi_node", "detach_volume"}, time.Now())
// Make sure Node is valid and new enough to support RPC
snap, err := a.srv.State().Snapshot()
if err != nil {
return err
}
_, err = getNodeForRpc(snap, args.NodeID)
if err != nil {
return err
}
// Get the connection to the client
state, ok := a.srv.getNodeConn(args.NodeID)
if !ok {
return findNodeConnAndForward(a.srv, args.NodeID, "ClientCSI.NodeDetachVolume", args, reply)
}
// Make the RPC
err = NodeRpc(state.Session, "CSI.NodeDetachVolume", args, reply)
if err != nil {
return fmt.Errorf("node detach volume: %v", err)
}
return nil
}
// clientIDsForController returns a shuffled list of client IDs where the
// controller plugin is expected to be running.
func (a *ClientCSI) clientIDsForController(pluginID string) ([]string, error) {
snap, err := a.srv.State().Snapshot()
if err != nil {
return nil, err
}
if pluginID == "" {
return nil, fmt.Errorf("missing plugin ID")
}
ws := memdb.NewWatchSet()
// note: plugin IDs are not scoped to region/DC but volumes are.
// so any node we get for a controller is already in the same
// region/DC for the volume.
plugin, err := snap.CSIPluginByID(ws, pluginID)
if err != nil {
return nil, fmt.Errorf("error getting plugin: %s, %v", pluginID, err)
}
if plugin == nil {
return nil, fmt.Errorf("plugin missing: %s", pluginID)
}
// iterating maps is "random" but unspecified and isn't particularly
// random with small maps, so not well-suited for load balancing.
// so we shuffle the keys and iterate over them.
clientIDs := []string{}
for clientID, controller := range plugin.Controllers {
if !controller.IsController() {
// we don't have separate types for CSIInfo depending on
// whether it's a controller or node. this error shouldn't
// make it to production but is to aid developers during
// development
continue
}
node, err := getNodeForRpc(snap, clientID)
if err == nil && node != nil && node.Ready() {
clientIDs = append(clientIDs, clientID)
}
}
if len(clientIDs) == 0 {
return nil, fmt.Errorf("failed to find clients running controller plugin %q", pluginID)
}
rand.Shuffle(len(clientIDs), func(i, j int) {
clientIDs[i], clientIDs[j] = clientIDs[j], clientIDs[i]
})
return clientIDs, nil
}