Add slice.UInt64s, helper type

Type properly encodes slice of uint64s as JSON array of strings

pkg/rbac/trace.go

@@ -1,17 +1,20 @@
 package rbac
 
-import "sort"
+import (
+	"github.com/cortezaproject/corteza-server/pkg/slice"
+	"sort"
+)
 
 type (
 	resolution string
 
 	Trace struct {
-		Resource   string     `json:"resource"`
-		Operation  string     `json:"operation"`
-		Access     Access     `json:"access"`
-		Roles      []uint64   `json:"roles"`
-		Rules      []*Rule    `json:"rules,omitempty"`
-		Resolution resolution `json:"resolution,omitempty"`
+		Resource   string        `json:"resource"`
+		Operation  string        `json:"operation"`
+		Access     Access        `json:"access"`
+		Roles      slice.UInt64s `json:"roles"`
+		Rules      []*Rule       `json:"rules,omitempty"`
+		Resolution resolution    `json:"resolution,omitempty"`
 	}
 )
 

pkg/slice/ints.go

@@ -1,5 +1,16 @@
 package slice
 
+import (
+	"bytes"
+	"strconv"
+)
+
+type (
+	// UInt64s represents slice of uint64 with some extra powers:
+	//  - encodes (JSON) uint64s as strings
+	UInt64s []uint64
+)
+
 func HasUint64(ss []uint64, s uint64) bool {
 	for i := range ss {
 		if ss[i] == s {
@@ -9,3 +20,23 @@ func HasUint64(ss []uint64, s uint64) bool {
 
 	return false
 }
+
+func (uu UInt64s) MarshalJSON() ([]byte, error) {
+	var (
+		buf = bytes.Buffer{}
+	)
+
+	buf.WriteByte('[')
+	for i, u := range uu {
+		if i > 0 {
+			buf.WriteByte(',')
+		}
+
+		buf.WriteByte('"')
+		buf.WriteString(strconv.FormatUint(u, 10))
+		buf.WriteByte('"')
+	}
+	buf.WriteByte(']')
+
+	return buf.Bytes(), nil
+}

pkg/slice/ints_test.go

@@ -1,7 +1,9 @@
 package slice
 
 import (
+	"encoding/json"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"testing"
 )
 
@@ -37,3 +39,38 @@ func TestHasUint64(t *testing.T) {
 		})
 	}
 }
+
+func TestUInt64s_MarshalJSON(t *testing.T) {
+	cases := []struct {
+		name string
+		ii   UInt64s
+		json string
+	}{
+		{
+			"empty",
+			UInt64s{},
+			`[]`,
+		},
+		{
+			"one",
+			UInt64s{285372959844073660},
+			`["285372959844073660"]`,
+		},
+		{
+			"two",
+			UInt64s{285372959844073660, 285372959844073661},
+			`["285372959844073660","285372959844073661"]`,
+		},
+	}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			var (
+				req         = require.New(t)
+				result, err = json.Marshal(c.ii)
+			)
+
+			req.NoError(err)
+			req.Equal(string(result), c.json)
+		})
+	}
+}