feat(transformers): convert absolute time to unix nano

Signed-off-by: Rodney Osodo <[email protected]>

pkg/transformers/json/transformer.go

@@ -187,7 +187,7 @@ func (ts *transformerService) transformTimeField(payload map[string]interface{})
 				return 0, err
 			}
 
-			return t.UnixNano(), nil
+			return transformers.ToUnixNano(t.UnixNano()), nil
 		}
 	}
 

pkg/transformers/senml/transformer.go

@@ -59,8 +59,16 @@ func (t transformer) Transform(msg *messaging.Message) (interface{}, error) {
 		// Use reception timestamp if SenML messsage Time is missing
 		t := v.Time
 		if t == 0 {
-			// Convert the Unix timestamp in nanoseconds to float64
-			t = float64(msg.GetCreated()) / float64(1e9)
+			t = float64(msg.GetCreated())
+		}
+
+		// If time is below 2**28 it is relative to the current time
+		// https://datatracker.ietf.org/doc/html/rfc8428#section-4.5.3
+		if t > 1<<28 {
+			t = transformers.ToUnixNano(t)
+		}
+		if v.UpdateTime > 1<<28 {
+			v.UpdateTime = transformers.ToUnixNano(v.UpdateTime)
 		}
 
 		msgs[i] = Message{

pkg/transformers/senml/transformer_test.go

@@ -17,7 +17,7 @@ import (
 
 func TestTransformJSON(t *testing.T) {
 	// Following hex-encoded bytes correspond to the content of:
-	// [{-2: "base-name", -3: 100.0, -4: "base-unit", -1: 10, -5: 10.0, -6: 100.0, 0: "name", 1: "unit", 6: 300.0, 7: 150.0, 2: 42.0, 5: 10.0}]
+	// [{"bn":"base-name","bt":100,"bu":"base-unit","bver":10,"bv":10,"bs":100,"n":"name","u":"unit","t":300,"ut":150,"v":42,"s":10}]
 	// For more details for mapping SenML labels to integers, please take a look here: https://tools.ietf.org/html/rfc8428#page-19.
 	jsonBytes, err := hex.DecodeString("5b7b22626e223a22626173652d6e616d65222c226274223a3130302c226275223a22626173652d756e6974222c2262766572223a31302c226276223a31302c226273223a3130302c226e223a226e616d65222c2275223a22756e6974222c2274223a3330302c227574223a3135302c2276223a34322c2273223a31307d5d")
 	assert.Nil(t, err, "Decoding JSON expected to succeed")

pkg/transformers/transformer.go

@@ -10,3 +10,28 @@ type Transformer interface {
 	// Transform Magistrala message to any other format.
 	Transform(msg *messaging.Message) (interface{}, error)
 }
+
+type number interface {
+	uint64 | int64 | float64
+}
+
+// ToUnixNano converts time to UnixNano time format.
+func ToUnixNano[N number](t N) N {
+	if t == 0 {
+		return 0
+	}
+	// Check if the value is in nanoseconds
+	if t > 1e18 {
+		return t
+	}
+	// Check if the value is in milliseconds
+	if t > 1e15 && t < 1e18 {
+		return t * 1e3
+	}
+	// Check if the value is in microseconds
+	if t > 1e12 && t < 1e15 {
+		return t * 1e6
+	}
+	// Assume it's in seconds (Unix time)
+	return t * 1e9
+}

pkg/transformers/transformer_test.go

@@ -0,0 +1,110 @@
+// Copyright (c) Abstract Machines
+// SPDX-License-Identifier: Apache-2.0
+
+package transformers_test
+
+import (
+	"testing"
+	"time"
+
+	"github.com/absmach/magistrala/pkg/transformers"
+)
+
+var now = time.Now()
+
+func TestInt64ToUnixNano(t *testing.T) {
+	cases := []struct {
+		desc string
+		time int64
+		want int64
+	}{
+		{
+			desc: "empty",
+			time: 0,
+			want: 0,
+		},
+		{
+			desc: "unix",
+			time: now.Unix(),
+			want: now.Unix() * int64(time.Second),
+		},
+		{
+			desc: "unix milli",
+			time: now.UnixMilli(),
+			want: now.UnixMilli() * int64(time.Millisecond),
+		},
+		{
+			desc: "unix micro",
+			time: now.UnixMicro(),
+			want: now.UnixMicro() * int64(time.Microsecond),
+		},
+		{
+			desc: "unix nano",
+			time: now.UnixNano(),
+			want: now.UnixNano(),
+		},
+	}
+
+	for _, c := range cases {
+		t.Run(c.desc, func(t *testing.T) {
+			got := transformers.ToUnixNano(c.time)
+			if got != c.want {
+				t.Errorf("ToUnixNano(%d) = %d; want %d", c.time, got, c.want)
+			}
+			t.Logf("ToUnixNano(%d) = %d; want %d", c.time, got, c.want)
+		})
+	}
+}
+
+func TestFloat64ToUnixNano(t *testing.T) {
+	cases := []struct {
+		desc string
+		time float64
+		want float64
+	}{
+		{
+			desc: "empty",
+			time: 0,
+			want: 0,
+		},
+		{
+			desc: "unix",
+			time: float64(now.Unix()),
+			want: float64(now.Unix() * int64(time.Second)),
+		},
+		{
+			desc: "unix milli",
+			time: float64(now.UnixMilli()),
+			want: float64(now.UnixMilli() * int64(time.Millisecond)),
+		},
+		{
+			desc: "unix micro",
+			time: float64(now.UnixMicro()),
+			want: float64(now.UnixMicro() * int64(time.Microsecond)),
+		},
+		{
+			desc: "unix nano",
+			time: float64(now.UnixNano()),
+			want: float64(now.UnixNano()),
+		},
+	}
+
+	for _, c := range cases {
+		t.Run(c.desc, func(t *testing.T) {
+			got := transformers.ToUnixNano(c.time)
+			if got != c.want {
+				t.Errorf("ToUnixNano(%f) = %f; want %f", c.time, got, c.want)
+			}
+			t.Logf("ToUnixNano(%f) = %f; want %f", c.time, got, c.want)
+		})
+	}
+}
+
+func BenchmarkToUnixNano(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		transformers.ToUnixNano(now.Unix())
+		transformers.ToUnixNano(now.UnixMilli())
+		transformers.ToUnixNano(now.UnixMicro())
+		transformers.ToUnixNano(now.UnixNano())
+	}
+}