csi/api: populate ReadAllocs/WriteAllocs fields

The API is missing values for `ReadAllocs` and `WriteAllocs` fields, resulting
in allocation claims not being populated in the web UI. These fields mirror
the fields in `nomad/structs.CSIVolume`. Returning a separate list of stubs
for read and write would be ideal, but this can't be done without either
bloating the API response with repeated full `Allocation` data, or causing a
panic in previous versions of the CLI.

The `nomad/structs` fields are persisted with nil values and are populated
during RPC, so we'll do the same in the HTTP API and populate the `ReadAllocs`
and `WriteAllocs` fields with a map of allocation IDs, but with null
values. The web UI will then create its `ReadAllocations` and
`WriteAllocations` fields by mapping from those IDs to the values in
`Allocations`, instead of flattening the map into a list.

api/csi.go

@@ -41,9 +41,6 @@ func (v *CSIVolumes) Info(id string, q *QueryOptions) (*CSIVolume, *QueryMeta, e
 		return nil, nil, err
 	}
 
-	// Cleanup allocation representation for the ui
-	resp.allocs()
-
 	return &resp, qm, nil
 }
 
@@ -110,11 +107,17 @@ type CSIVolume struct {
 	Parameters     map[string]string       `hcl:"parameters"`
 	Context        map[string]string       `hcl:"context"`
 
-	// Allocations, tracking claim status
-	ReadAllocs  map[string]*Allocation
+	// ReadAllocs is a map of allocation IDs for tracking reader claim status.
+	// The Allocation value will always be nil; clients can populate this data
+	// by iterating over the Allocations field.
+	ReadAllocs map[string]*Allocation
+
+	// WriteAllocs is a map of allocation IDs for tracking writer claim
+	// status. The Allocation value will always be nil; clients can populate
+	// this data by iterating over the Allocations field.
 	WriteAllocs map[string]*Allocation
 
-	// Combine structs.{Read,Write}Allocs
+	// Allocations is a combined list of readers and writers
 	Allocations []*AllocationListStub
 
 	// Schedulable is true if all the denormalized plugin health fields are true
@@ -136,21 +139,6 @@ type CSIVolume struct {
 	ExtraKeysHCL []string `hcl1:",unusedKeys" json:"-"`
 }
 
-// allocs is called after we query the volume (creating this CSIVolume struct) to collapse
-// allocations for the UI
-func (v *CSIVolume) allocs() {
-	for _, a := range v.WriteAllocs {
-		if a != nil {
-			v.Allocations = append(v.Allocations, a.Stub())
-		}
-	}
-	for _, a := range v.ReadAllocs {
-		if a != nil {
-			v.Allocations = append(v.Allocations, a.Stub())
-		}
-	}
-}
-
 type CSIVolumeIndexSort []*CSIVolumeListStub
 
 func (v CSIVolumeIndexSort) Len() int {

command/agent/csi_endpoint.go

@@ -310,7 +310,7 @@ func structsCSIVolumeToApi(vol *structs.CSIVolume) *api.CSIVolume {
 		return nil
 	}
 
-	allocs := len(vol.WriteAllocs) + len(vol.ReadAllocs)
+	allocCount := len(vol.ReadAllocs) + len(vol.WriteAllocs)
 
 	out := &api.CSIVolume{
 		ID:             vol.ID,
@@ -326,7 +326,11 @@ func structsCSIVolumeToApi(vol *structs.CSIVolume) *api.CSIVolume {
 		Context:        vol.Context,
 
 		// Allocations is the collapsed list of both read and write allocs
-		Allocations: make([]*api.AllocationListStub, 0, allocs),
+		Allocations: make([]*api.AllocationListStub, 0, allocCount),
+
+		// tracking of volume claims
+		ReadAllocs:  map[string]*api.Allocation{},
+		WriteAllocs: map[string]*api.Allocation{},
 
 		Schedulable:         vol.Schedulable,
 		PluginID:            vol.PluginID,
@@ -342,15 +346,28 @@ func structsCSIVolumeToApi(vol *structs.CSIVolume) *api.CSIVolume {
 		ModifyIndex:         vol.ModifyIndex,
 	}
 
+	// WriteAllocs and ReadAllocs will only ever contain the Allocation ID,
+	// with a null value for the Allocation; these IDs are mapped to
+	// allocation stubs in the Allocations field. This indirection is so the
+	// API can support both the UI and CLI consumer in a safely backwards
+	// compatible way
 	for _, a := range vol.WriteAllocs {
 		if a != nil {
-			out.Allocations = append(out.Allocations, structsAllocListStubToApi(a.Stub(nil)))
+			alloc := structsAllocListStubToApi(a.Stub(nil))
+			if alloc != nil {
+				out.WriteAllocs[alloc.ID] = nil
+				out.Allocations = append(out.Allocations, alloc)
+			}
 		}
 	}
 
 	for _, a := range vol.ReadAllocs {
 		if a != nil {
-			out.Allocations = append(out.Allocations, structsAllocListStubToApi(a.Stub(nil)))
+			alloc := structsAllocListStubToApi(a.Stub(nil))
+			if alloc != nil {
+				out.ReadAllocs[alloc.ID] = nil
+				out.Allocations = append(out.Allocations, alloc)
+			}
 		}
 	}
 

ui/app/serializers/volume.js

@@ -23,17 +23,16 @@ export default class VolumeSerializer extends ApplicationSerializer {
     hash.ID = JSON.stringify([`csi/${hash.ID}`, hash.NamespaceID || 'default']);
     hash.PluginID = `csi/${hash.PluginID}`;
 
-    // Convert hash-based allocation embeds to lists
+    // Populate read/write allocation lists from aggregate allocation list
     const readAllocs = hash.ReadAllocs || {};
     const writeAllocs = hash.WriteAllocs || {};
-    const bindIDToAlloc = hash => id => {
-      const alloc = hash[id];
-      alloc.ID = id;
+    const bindIDToAlloc = allocList => id => {
+      const alloc = allocList.find(a => a.ID === id);
       return alloc;
     };
 
-    hash.ReadAllocations = Object.keys(readAllocs).map(bindIDToAlloc(readAllocs));
-    hash.WriteAllocations = Object.keys(writeAllocs).map(bindIDToAlloc(writeAllocs));
+    hash.ReadAllocations = Object.keys(readAllocs).map(bindIDToAlloc(hash.Allocations));
+    hash.WriteAllocations = Object.keys(writeAllocs).map(bindIDToAlloc(hash.Allocations));
 
     const normalizedHash = super.normalize(typeHash, hash);
     return this.extractEmbeddedRecords(this, this.store, typeHash, normalizedHash);

ui/mirage/models/csi-volume.js

@@ -4,4 +4,5 @@ export default Model.extend({
   plugin: belongsTo('csi-plugin'),
   writeAllocs: hasMany('allocation'),
   readAllocs: hasMany('allocation'),
+  allocations: hasMany('allocation'),
 });

ui/mirage/serializers/csi-volume.js

@@ -9,7 +9,7 @@ const groupBy = (list, attr) => {
 
 export default ApplicationSerializer.extend({
   embed: true,
-  include: ['writeAllocs', 'readAllocs'],
+  include: ['writeAllocs', 'readAllocs', 'allocations'],
 
   serialize() {
     var json = ApplicationSerializer.prototype.serialize.apply(this, arguments);

ui/tests/acceptance/volume-detail-test.js

@@ -9,11 +9,13 @@ import VolumeDetail from 'nomad-ui/tests/pages/storage/volumes/detail';
 
 const assignWriteAlloc = (volume, alloc) => {
   volume.writeAllocs.add(alloc);
+  volume.allocations.add(alloc);
   volume.save();
 };
 
 const assignReadAlloc = (volume, alloc) => {
   volume.readAllocs.add(alloc);
+  volume.allocations.add(alloc);
   volume.save();
 };
 

ui/tests/acceptance/volumes-list-test.js

@@ -9,11 +9,13 @@ import Layout from 'nomad-ui/tests/pages/layout';
 
 const assignWriteAlloc = (volume, alloc) => {
   volume.writeAllocs.add(alloc);
+  volume.allocations.add(alloc);
   volume.save();
 };
 
 const assignReadAlloc = (volume, alloc) => {
   volume.readAllocs.add(alloc);
+  volume.allocations.add(alloc);
   volume.save();
 };
 

ui/tests/unit/serializers/volume-test.js

@@ -173,30 +173,38 @@ module('Unit | Serializer | Volume', function(hooks) {
         NodesExpected: 2,
         CreateIndex: 1,
         ModifyIndex: 38,
-        WriteAllocs: {
-          'alloc-id-1': {
+        Allocations: [
+          {
+            ID: 'alloc-id-1',
             TaskGroup: 'foobar',
             CreateTime: +REF_DATE * 1000000,
             ModifyTime: +REF_DATE * 1000000,
             JobID: 'the-job',
             Namespace: 'namespace-2',
           },
-          'alloc-id-2': {
+          {
+            ID: 'alloc-id-2',
             TaskGroup: 'write-here',
             CreateTime: +REF_DATE * 1000000,
             ModifyTime: +REF_DATE * 1000000,
             JobID: 'the-job',
             Namespace: 'namespace-2',
           },
-        },
-        ReadAllocs: {
-          'alloc-id-3': {
+          {
+            ID: 'alloc-id-3',
             TaskGroup: 'look-if-you-must',
             CreateTime: +REF_DATE * 1000000,
             ModifyTime: +REF_DATE * 1000000,
             JobID: 'the-job',
             Namespace: 'namespace-2',
           },
+        ],
+        WriteAllocs: {
+          'alloc-id-1': null,
+          'alloc-id-2': null,
+        },
+        ReadAllocs: {
+          'alloc-id-3': null,
         },
       },
       out: {

website/pages/api-docs/volumes.mdx

@@ -230,6 +230,10 @@ $ curl \
       "ModifyTime": 1495747371794276400
     }
   ],
+  "ReadAllocs": {
+    "a8198d79-cfdb-6593-a999-1e9adabcba2e": null
+  },
+  "WriteAllocs": {},
   "Schedulable": true,
   "PluginID": "plugin-id1",
   "Provider": "ebs",