Add sorting to partition store

Extend the partition store to parse the "sort" query parameter as a
sorting condition. Dot notation is used to denote the object field.
Preceding the key with "-" denotes descending (reverse) order.

Example sorting by name:

GET /v1/secrets?sort=metadata.name

Reverse sorting by name:

GET /v1/secrets?sort=-metadata.name

All values are converted to strings and sorted lexicographically.

pkg/stores/partition/listprocessor/processor.go

@@ -2,6 +2,7 @@
 package listprocessor
 
 import (
+	"sort"
 	"strconv"
 	"strings"
 
@@ -16,6 +17,7 @@ const (
 	continueParam = "continue"
 	limitParam    = "limit"
 	filterParam   = "filter"
+	sortParam     = "sort"
 )
 
 // ListOptions represents the query parameters that may be included in a list request.
@@ -23,6 +25,7 @@ type ListOptions struct {
 	ChunkSize int
 	Resume    string
 	Filters   []Filter
+	Sort      Sort
 }
 
 // Filter represents a field to filter by.
@@ -33,6 +36,25 @@ type Filter struct {
 	match string
 }
 
+// SortOrder represents whether the list should be ascending or descending.
+type SortOrder int
+
+const (
+	// ASC stands for ascending order.
+	ASC SortOrder = iota
+	// DESC stands for descending (reverse) order.
+	DESC
+)
+
+// Sort represents the criteria to sort on.
+// The subfield to sort by is represented in a request query using . notation, e.g. 'metadata.name'.
+// The subfield is internally represented as a slice, e.g. [metadata, name].
+// The order is represented by prefixing the sort key by '-', e.g. sort=-metadata.name.
+type Sort struct {
+	field []string
+	order SortOrder
+}
+
 // ParseQuery parses the query params of a request and returns a ListOptions.
 func ParseQuery(apiOp *types.APIRequest) *ListOptions {
 	chunkSize := getLimit(apiOp)
@@ -47,10 +69,20 @@ func ParseQuery(apiOp *types.APIRequest) *ListOptions {
 		}
 		filterOpts = append(filterOpts, Filter{field: strings.Split(filter[0], "."), match: filter[1]})
 	}
+	sort := Sort{}
+	sortKey := q.Get(sortParam)
+	if sortKey != "" && sortKey[0] == '-' {
+		sort.order = DESC
+		sortKey = sortKey[1:]
+	}
+	if sortKey != "" {
+		sort.field = strings.Split(sortKey, ".")
+	}
 	return &ListOptions{
 		ChunkSize: chunkSize,
 		Resume:    cont,
 		Filters:   filterOpts,
+		Sort:      sort,
 	}
 }
 
@@ -148,3 +180,19 @@ func matchesAll(obj map[string]interface{}, filters []Filter) bool {
 	}
 	return true
 }
+
+// SortList sorts the slice by the provided sort criteria.
+func SortList(list []unstructured.Unstructured, s Sort) []unstructured.Unstructured {
+	if len(s.field) == 0 {
+		return list
+	}
+	sort.Slice(list, func(i, j int) bool {
+		iField := convert.ToString(data.GetValueN(list[i].Object, s.field...))
+		jField := convert.ToString(data.GetValueN(list[j].Object, s.field...))
+		if s.order == ASC {
+			return iField < jField
+		}
+		return jField < iField
+	})
+	return list
+}

pkg/stores/partition/listprocessor/processor_test.go

@@ -796,3 +796,322 @@ func TestFilterList(t *testing.T) {
 		})
 	}
 }
+
+func TestSortList(t *testing.T) {
+	tests := []struct {
+		name    string
+		objects []unstructured.Unstructured
+		sort    Sort
+		want    []unstructured.Unstructured
+	}{
+		{
+			name: "sort metadata.name",
+			objects: []unstructured.Unstructured{
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "fuji",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "honeycrisp",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "granny-smith",
+						},
+						"data": map[string]interface{}{
+							"color": "green",
+						},
+					},
+				},
+			},
+			sort: Sort{
+				field: []string{"metadata", "name"},
+			},
+			want: []unstructured.Unstructured{
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "fuji",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "granny-smith",
+						},
+						"data": map[string]interface{}{
+							"color": "green",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "honeycrisp",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "reverse sort metadata.name",
+			objects: []unstructured.Unstructured{
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "fuji",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "honeycrisp",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "granny-smith",
+						},
+						"data": map[string]interface{}{
+							"color": "green",
+						},
+					},
+				},
+			},
+			sort: Sort{
+				field: []string{"metadata", "name"},
+				order: DESC,
+			},
+			want: []unstructured.Unstructured{
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "honeycrisp",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "granny-smith",
+						},
+						"data": map[string]interface{}{
+							"color": "green",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "fuji",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "invalid field",
+			objects: []unstructured.Unstructured{
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "granny-smith",
+						},
+						"data": map[string]interface{}{
+							"color": "green",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "fuji",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "honeycrisp",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+			},
+			sort: Sort{
+				field: []string{"data", "productType"},
+			},
+			want: []unstructured.Unstructured{
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "granny-smith",
+						},
+						"data": map[string]interface{}{
+							"color": "green",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "fuji",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "honeycrisp",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "unsorted",
+			objects: []unstructured.Unstructured{
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "granny-smith",
+						},
+						"data": map[string]interface{}{
+							"color": "green",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "fuji",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "honeycrisp",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+			},
+			sort: Sort{},
+			want: []unstructured.Unstructured{
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "granny-smith",
+						},
+						"data": map[string]interface{}{
+							"color": "green",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "fuji",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+				{
+					Object: map[string]interface{}{
+						"kind": "apple",
+						"metadata": map[string]interface{}{
+							"name": "honeycrisp",
+						},
+						"data": map[string]interface{}{
+							"color": "pink",
+						},
+					},
+				},
+			},
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			got := SortList(test.objects, test.sort)
+			assert.Equal(t, test.want, got)
+		})
+	}
+}

pkg/stores/partition/store.go

@@ -128,6 +128,7 @@ func (s *Store) List(apiOp *types.APIRequest, schema *types.APISchema) (types.AP
 	}
 
 	list := listprocessor.FilterList(stream, opts.Filters)
+	list = listprocessor.SortList(list, opts.Sort)
 
 	for _, item := range list {
 		item := item

pkg/stores/partition/store_test.go

@@ -278,6 +278,85 @@ func TestList(t *testing.T) {
 				},
 			},
 		},
+		{
+			name: "with sorting",
+			apiOps: []*types.APIRequest{
+				newRequest("sort=metadata.name"),
+				newRequest("sort=-metadata.name"),
+			},
+			partitions: []Partition{
+				mockPartition{
+					name: "all",
+				},
+			},
+			objects: map[string]*unstructured.UnstructuredList{
+				"all": {
+					Items: []unstructured.Unstructured{
+						newApple("fuji").Unstructured,
+						newApple("granny-smith").Unstructured,
+						newApple("bramley").Unstructured,
+						newApple("crispin").Unstructured,
+					},
+				},
+			},
+			want: []types.APIObjectList{
+				{
+					Objects: []types.APIObject{
+						newApple("bramley").toObj(),
+						newApple("crispin").toObj(),
+						newApple("fuji").toObj(),
+						newApple("granny-smith").toObj(),
+					},
+				},
+				{
+					Objects: []types.APIObject{
+						newApple("granny-smith").toObj(),
+						newApple("fuji").toObj(),
+						newApple("crispin").toObj(),
+						newApple("bramley").toObj(),
+					},
+				},
+			},
+		},
+		{
+			name: "multi-partition sort=metadata.name",
+			apiOps: []*types.APIRequest{
+				newRequest("sort=metadata.name"),
+			},
+			partitions: []Partition{
+				mockPartition{
+					name: "green",
+				},
+				mockPartition{
+					name: "yellow",
+				},
+			},
+			objects: map[string]*unstructured.UnstructuredList{
+				"pink": {
+					Items: []unstructured.Unstructured{
+						newApple("fuji").Unstructured,
+					},
+				},
+				"green": {
+					Items: []unstructured.Unstructured{
+						newApple("granny-smith").Unstructured,
+					},
+				},
+				"yellow": {
+					Items: []unstructured.Unstructured{
+						newApple("crispin").Unstructured,
+					},
+				},
+			},
+			want: []types.APIObjectList{
+				{
+					Objects: []types.APIObject{
+						newApple("crispin").toObj(),
+						newApple("granny-smith").toObj(),
+					},
+				},
+			},
+		},
 	}
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {