[pkg/ottl]: Add ByteSliceLikeGetter interface

.chloggen/add-byteslicelikegetter.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: pkg/ottl
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add ByteSliceLikeGetter interface
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [31929]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [api]

pkg/ottl/LANGUAGE.md

@@ -69,6 +69,7 @@ The following types are supported for single-value parameters in OTTL functions:
 - `IntLikeGetter`
 - `BoolGetter`
 - `BoolLikeGetter`
+- `ByteSliceLikeGetter`
 - `Enum`
 - `string`
 - `float64`

pkg/ottl/expression.go

@@ -7,6 +7,7 @@ import (
 	"context"
 	"encoding/hex"
 	"fmt"
+	"math"
 	"reflect"
 	"strconv"
 	"time"
@@ -549,6 +550,89 @@ func (g StandardIntLikeGetter[K]) Get(ctx context.Context, tCtx K) (*int64, erro
 	return &result, nil
 }
 
+// ByteSliceLikeGetter is a Getter that returns []byte by converting the underlying value to an []byte if necessary
+type ByteSliceLikeGetter[K any] interface {
+	// Get retrieves []byte value.
+	// The expectation is that the underlying value is converted to []byte if possible.
+	// If the value cannot be converted to []byte, nil and an error are returned.
+	// If the value is nil, nil is returned without an error.
+	Get(ctx context.Context, tCtx K) (byteSlice, error)
+}
+
+type StandardByteSliceLikeGetter[K any] struct {
+	Getter func(ctx context.Context, tCtx K) (any, error)
+}
+
+//nolint:revive
+func (g StandardByteSliceLikeGetter[K]) Get(ctx context.Context, tCtx K) (byteSlice, error) {
+	val, err := g.Getter(ctx, tCtx)
+	if err != nil {
+		return nil, fmt.Errorf("error getting value in %T: %w", g, err)
+	}
+	if val == nil {
+		return nil, nil
+	}
+	var result byteSlice
+	switch v := val.(type) {
+	case byteSlice:
+		result = v
+	case []byte:
+		result = v
+	case string:
+		result = []byte(v)
+	case float64:
+		result = float64ToBytes(v)
+	case int64:
+		result = int64ToBytes(v)
+	case bool:
+		if v {
+			result = []byte("1")
+		} else {
+			result = []byte("0")
+		}
+	case pcommon.Value:
+		switch v.Type() {
+		case pcommon.ValueTypeBytes:
+			result = v.Bytes().AsRaw()
+		case pcommon.ValueTypeInt:
+			result = int64ToBytes(v.Int())
+		case pcommon.ValueTypeDouble:
+			result = float64ToBytes(v.Double())
+		case pcommon.ValueTypeStr:
+			result = []byte(v.Str())
+		case pcommon.ValueTypeBool:
+			if v.Bool() {
+				result = []byte("1")
+			} else {
+				result = []byte("0")
+			}
+		default:
+			return nil, TypeError(fmt.Sprintf("unsupported value type: %v", v.Type()))
+		}
+	default:
+		return nil, TypeError(fmt.Sprintf("unsupported type: %T", v))
+	}
+	return result, nil
+}
+
+func float64ToBytes(f float64) []byte {
+	bits := math.Float64bits(f)
+	bytes := make([]byte, 8)
+	for i := 0; i < 8; i++ {
+		bytes[i] = byte(bits >> (56 - 8*i))
+	}
+	return bytes
+}
+
+func int64ToBytes(i int64) []byte {
+	b := make([]byte, 8)
+	for j := 7; j >= 0; j-- {
+		b[j] = byte(i & 0xff)
+		i >>= 8
+	}
+	return b
+}
+
 // BoolLikeGetter is a Getter that returns a bool by converting the underlying value to a bool if necessary.
 type BoolLikeGetter[K any] interface {
 	// Get retrieves a bool value.

pkg/ottl/expression_test.go

@@ -1449,6 +1449,215 @@ func Test_StandardIntLikeGetter_WrappedError(t *testing.T) {
 	assert.False(t, ok)
 }
 
+func Test_StandardByteSliceLikeGetter(t *testing.T) {
+	tests := []struct {
+		name             string
+		getter           ByteSliceLikeGetter[any]
+		want             any
+		valid            bool
+		expectedErrorMsg string
+	}{
+		{
+			name: "string type",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					return "1", nil
+				},
+			},
+			want:  byteSlice("1"),
+			valid: true,
+		},
+		{
+			name: "byte type",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					return []byte("1"), nil
+				},
+			},
+			want:  byteSlice("1"),
+			valid: true,
+		},
+		{
+			name: "byteSlice type",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					return byteSlice("1"), nil
+				},
+			},
+			want:  byteSlice("1"),
+			valid: true,
+		},
+		{
+			name: "int64 type",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					return int64(12), nil
+				},
+			},
+			want:  byteSlice(int64ToBytes(12)),
+			valid: true,
+		},
+		{
+			name: "float64 type",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					return 1.1, nil
+				},
+			},
+			want:  byteSlice(float64ToBytes(1.1)),
+			valid: true,
+		},
+		{
+			name: "primitive bool true",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					return true, nil
+				},
+			},
+			want:  byteSlice("1"),
+			valid: true,
+		},
+		{
+			name: "primitive bool false",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					return false, nil
+				},
+			},
+			want:  byteSlice("0"),
+			valid: true,
+		},
+		{
+			name: "pcommon.value type int",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					v := pcommon.NewValueInt(int64(100))
+					return v, nil
+				},
+			},
+			want:  byteSlice(int64ToBytes(100)),
+			valid: true,
+		},
+		{
+			name: "pcommon.value type float",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					v := pcommon.NewValueDouble(float64(1.9))
+					return v, nil
+				},
+			},
+			want:  byteSlice(float64ToBytes(1.9)),
+			valid: true,
+		},
+		{
+			name: "pcommon.value type string",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					v := pcommon.NewValueStr("12")
+					return v, nil
+				},
+			},
+			want:  byteSlice("12"),
+			valid: true,
+		},
+		{
+			name: "pcommon.value type bytes",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					v := pcommon.NewValueBytes()
+					v.SetEmptyBytes().Append(byte(12))
+					return v, nil
+				},
+			},
+			want:  byteSlice{12},
+			valid: true,
+		},
+		{
+			name: "pcommon.value type bool true",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					v := pcommon.NewValueBool(true)
+					return v, nil
+				},
+			},
+			want:  byteSlice("1"),
+			valid: true,
+		},
+		{
+			name: "pcommon.value type bool false",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					v := pcommon.NewValueBool(false)
+					return v, nil
+				},
+			},
+			want:  byteSlice("0"),
+			valid: true,
+		},
+		{
+			name: "nil",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					return nil, nil
+				},
+			},
+			want:  nil,
+			valid: true,
+		},
+		{
+			name: "invalid type",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					return map[string]string{}, nil
+				},
+			},
+			valid:            false,
+			expectedErrorMsg: "unsupported type: map[string]string",
+		},
+		{
+			name: "invalid pcommon.Value type",
+			getter: StandardByteSliceLikeGetter[any]{
+				Getter: func(_ context.Context, _ any) (any, error) {
+					v := pcommon.NewValueMap()
+					return v, nil
+				},
+			},
+			valid:            false,
+			expectedErrorMsg: "unsupported value type: Map",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			val, err := tt.getter.Get(context.Background(), nil)
+			if tt.valid {
+				assert.NoError(t, err)
+				if tt.want == nil {
+					assert.Nil(t, val)
+				} else {
+					assert.Equal(t, tt.want, val)
+				}
+			} else {
+				assert.IsType(t, TypeError(""), err)
+				assert.EqualError(t, err, tt.expectedErrorMsg)
+			}
+		})
+	}
+}
+
+// nolint:errorlint
+func Test_StandardByteSliceLikeGetter_WrappedError(t *testing.T) {
+	getter := StandardByteSliceLikeGetter[any]{
+		Getter: func(_ context.Context, _ any) (any, error) {
+			return nil, TypeError("")
+		},
+	}
+	_, err := getter.Get(context.Background(), nil)
+	assert.Error(t, err)
+	_, ok := err.(TypeError)
+	assert.False(t, ok)
+}
+
 func Test_StandardBoolGetter(t *testing.T) {
 	tests := []struct {
 		name             string

pkg/ottl/functions.go

@@ -493,6 +493,12 @@ func (p *Parser[K]) buildArg(argVal value, argType reflect.Type) (any, error) {
 			return nil, err
 		}
 		return StandardBoolLikeGetter[K]{Getter: arg.Get}, nil
+	case strings.HasPrefix(name, "ByteSliceLikeGetter"):
+		arg, err := p.newGetter(argVal)
+		if err != nil {
+			return nil, err
+		}
+		return StandardByteSliceLikeGetter[K]{Getter: arg.Get}, nil
 	case name == "Enum":
 		arg, err := p.enumParser((*EnumSymbol)(argVal.Enum))
 		if err != nil {