[pkg/ottl]: Add ByteSliceLikeGetter interface (#33536)

**Description:** <Describe what has changed.>
Adds ByteSliceLikeGetter interface due to future support of Hex()
converter

**Link to tracking Issue:** #31929 

**Testing:** <Describe what testing was performed and which tests were
added.>

**Documentation:** <Describe the documentation added.>

---------

Signed-off-by: odubajDT <[email protected]>

.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

@@ -4,7 +4,9 @@
 package ottl // import "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl"
 
 import (
+ "bytes"
  "context"
+ "encoding/binary"
  "encoding/hex"
  "fmt"
  "reflect"
@@ -549,6 +551,81 @@ 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) ([]byte, error)
+}
+
+type StandardByteSliceLikeGetter[K any] struct {
+ Getter func(ctx context.Context, tCtx K) (any, error)
+}
+
+func (g StandardByteSliceLikeGetter[K]) Get(ctx context.Context, tCtx K) ([]byte, 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 []byte
+ switch v := val.(type) {
+ case []byte:
+ result = v
+ case string:
+ result = []byte(v)
+ case float64, int64, bool:
+ result, err = valueToBytes(v)
+ if err != nil {
+ return nil, fmt.Errorf("error converting value %f of %T: %w", v, g, err)
+ }
+ case pcommon.Value:
+ switch v.Type() {
+ case pcommon.ValueTypeBytes:
+ result = v.Bytes().AsRaw()
+ case pcommon.ValueTypeInt:
+ result, err = valueToBytes(v.Int())
+ if err != nil {
+ return nil, fmt.Errorf("error converting value %d of int64: %w", v.Int(), err)
+ }
+ case pcommon.ValueTypeDouble:
+ result, err = valueToBytes(v.Double())
+ if err != nil {
+ return nil, fmt.Errorf("error converting value %f of float64: %w", v.Double(), err)
+ }
+ case pcommon.ValueTypeStr:
+ result = []byte(v.Str())
+ case pcommon.ValueTypeBool:
+ result, err = valueToBytes(v.Bool())
+ if err != nil {
+ return nil, fmt.Errorf("error converting value %s of bool: %w", v.Str(), err)
+ }
+ 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
+}
+
+// valueToBytes converts a value to a byte slice of length 8.
+func valueToBytes(n any) ([]byte, error) {
+ // Create a buffer to hold the bytes
+ buf := new(bytes.Buffer)
+ // Write the value to the buffer using binary.Write
+ err := binary.Write(buf, binary.BigEndian, n)
+ if err != nil {
+ return nil, err
+ }
+
+ return buf.Bytes(), nil
+}
+
 // 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 +1449,205 @@ 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: []byte{49},
+ valid: true,
+ },
+ {
+ name: "byte type",
+ getter: StandardByteSliceLikeGetter[any]{
+ Getter: func(_ context.Context, _ any) (any, error) {
+ return []byte{49}, nil
+ },
+ },
+ want: []byte{49},
+ valid: true,
+ },
+ {
+ name: "int64 type",
+ getter: StandardByteSliceLikeGetter[any]{
+ Getter: func(_ context.Context, _ any) (any, error) {
+ return int64(12), nil
+ },
+ },
+ want: []byte{0, 0, 0, 0, 0, 0, 0, 12},
+ valid: true,
+ },
+ {
+ name: "float64 type",
+ getter: StandardByteSliceLikeGetter[any]{
+ Getter: func(_ context.Context, _ any) (any, error) {
+ return 1.1, nil
+ },
+ },
+ want: []byte{63, 241, 153, 153, 153, 153, 153, 154},
+ valid: true,
+ },
+ {
+ name: "primitive bool true",
+ getter: StandardByteSliceLikeGetter[any]{
+ Getter: func(_ context.Context, _ any) (any, error) {
+ return true, nil
+ },
+ },
+ want: []byte{1},
+ valid: true,
+ },
+ {
+ name: "primitive bool false",
+ getter: StandardByteSliceLikeGetter[any]{
+ Getter: func(_ context.Context, _ any) (any, error) {
+ return false, nil
+ },
+ },
+ want: []byte{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: []byte{0, 0, 0, 0, 0, 0, 0, 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: []byte{63, 254, 102, 102, 102, 102, 102, 102},
+ valid: true,
+ },
+ {
+ name: "pcommon.value type string",
+ getter: StandardByteSliceLikeGetter[any]{
+ Getter: func(_ context.Context, _ any) (any, error) {
+ v := pcommon.NewValueStr("1")
+ return v, nil
+ },
+ },
+ want: []byte{49},
+ 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: []byte{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: []byte{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: []byte{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 {

pkg/ottl/functions_test.go

@@ -1207,6 +1207,20 @@ func Test_NewFunctionCall(t *testing.T) {
  },
  want: nil,
  },
+ {
+ name: "byteslicelikegetter arg",
+ inv: editor{
+ Function: "testing_byte_slice",
+ Arguments: []argument{
+ {
+ Value: value{
+ Bytes: &byteSlice{1},
+ },
+ },
+ },
+ },
+ want: nil,
+ },
  {
  name: "pmapgetter arg",
  inv: editor{
@@ -1864,6 +1878,16 @@ func functionWithIntLikeGetter(IntLikeGetter[any]) (ExprFunc[any], error) {
  }, nil
 }
 
+type byteSliceLikeGetterArguments struct {
+ ByteSliceLikeGetterArg ByteSliceLikeGetter[any]
+}
+
+func functionWithByteSliceLikeGetter(ByteSliceLikeGetter[any]) (ExprFunc[any], error) {
+ return func(context.Context, any) (any, error) {
+ return "anything", nil
+ }, nil
+}
+
 type pMapGetterArguments struct {
  PMapArg PMapGetter[any]
 }
@@ -2150,6 +2174,11 @@ func defaultFunctionsForTests() map[string]Factory[any] {
  &intLikeGetterArguments{},
  functionWithIntLikeGetter,
  ),
+ createFactory[any](
+ "testing_byteslicelikegetter",
+ &byteSliceLikeGetterArguments{},
+ functionWithByteSliceLikeGetter,
+ ),
  createFactory[any](
  "testing_pmapgetter",
  &pMapGetterArguments{},