Make reason field required in CSI spec

Author: gnufied

csi.proto

@@ -1074,7 +1074,9 @@ message VolumeHealth {
 
     // A brief CamelCase string that describes the condition and is
     // suitable for machine parsing and concise CLI display.
-    // This field is OPTIONAL.
+    // The Plugin MUST NOT return multiple VolumeHealthEntry messages
+    // for the same volume with the same (status, reason) combination.
+    // This field is REQUIRED.
     string reason = 2;
 
     // A user friendly description of the volume health condition.
@@ -1805,7 +1807,9 @@ message NodeGetStorageHealthResponse {
 
     // A brief CamelCase string that describes the condition and is
     // suitable for machine parsing and concise CLI display.
-    // This field is OPTIONAL.
+    // The Plugin MUST NOT return multiple StorageBackendHealth messages
+    // with the same (status, reason, volume_capability) combination.
+    // This field is REQUIRED.
     string reason = 2;
 
     // A user friendly description of the storage health condition.

lib/go/csi/csi.pb.go

@@ -1718,7 +1718,9 @@ message VolumeHealth {
 
     // A brief CamelCase string that describes the condition and is
     // suitable for machine parsing and concise CLI display.
-    // This field is OPTIONAL.
+    // The Plugin MUST NOT return multiple VolumeHealthEntry messages
+    // for the same volume with the same (status, reason) combination.
+    // This field is REQUIRED.
     string reason = 2;
 
     // A user friendly description of the volume health condition.
@@ -3007,7 +3009,9 @@ message NodeGetStorageHealthResponse {
 
     // A brief CamelCase string that describes the condition and is
     // suitable for machine parsing and concise CLI display.
-    // This field is OPTIONAL.
+    // The Plugin MUST NOT return multiple StorageBackendHealth messages
+    // with the same (status, reason, volume_capability) combination.
+    // This field is REQUIRED.
     string reason = 2;
 
     // A user friendly description of the storage health condition.