[pkg/ottl] Accept string (32 byte hex) {span,trace,profile} IDs (open-telemetry#43882)

#### Description

Currently `{TraceID,SpanID,ProfileID}` only support byte IDs, however in
open-telemetry#43429
it was brought up that it is difficult to take a string representation
of an ID and directly use that to set a trace ID. This would be for a
hexadecimal string representation comprising 32 bytes. This change
allows the `{TraceID,SpanID,ProfileID}` functions to also work on string
inputs.

In short, the following now works:

```yaml
statements:
  - set(span.trace_id, TraceID("a389023abaa839283293ed323892389d"))
```

#### Link to tracking issue
Fixes
open-telemetry#43429

#### Testing

In addition to the included go tests the following config 


[test-str-trace.yml](https://github.com/user-attachments/files/23217501/test-str-trace.yml)

was used to manually test by invoking `make otelcontribcol &&
./bin/otelcontribcol_darwin_arm64 --config test-str-trace.yml` in one
window and `telemetrygen traces --otlp-insecure --traces 1` in another.
The output is as shown:
<details>
<summary>CLI Output</summary>

```
Span #0
    Trace ID       : a389023abaa839283293ed323892389d
    Parent ID      : e5c516b0c8942eab
    ID             : 1914136d5f9ca838
    Name           : okey-dokey-0
    Kind           : Server
    Start time     : 2025-10-29 18:59:03.312829 +0000 UTC
    End time       : 2025-10-29 18:59:03.312952 +0000 UTC
    Status code    : Unset
    Status message :
Attributes:
     -> network.peer.address: Str(1.2.3.4)
     -> peer.service: Str(telemetrygen-client)
Span #1
    Trace ID       : a389023abaa839283293ed323892389d
    Parent ID      :
    ID             : e5c516b0c8942eab
    Name           : lets-go
    Kind           : Client
    Start time     : 2025-10-29 18:59:03.312829 +0000 UTC
    End time       : 2025-10-29 18:59:03.312952 +0000 UTC
    Status code    : Unset
    Status message :
Attributes:
     -> network.peer.address: Str(1.2.3.4)
     -> peer.service: Str(telemetrygen-server)
```

</details>

#### Documentation

I don't currently see documentation for these functions, but I'm new
here, maybe I'm missing something? Glad to update it

---------

Co-authored-by: Edmo Vamerlatti Costa <[email protected]>

Author: andrewvc

.chloggen/accept-str-traceids.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. receiver/filelog)
+component: pkg/ottl
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Accept string trace/span/profile IDs for `TraceID()`, `SpanID()`, and `ProfileID()` in OTTL.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [43429]
+
+# (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: This change allows for a more straightforward use of string values to set trace, span, and profile IDs in OTTL.
+
+# 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: [user]

pkg/ottl/e2e/e2e_test.go

@@ -1110,6 +1110,12 @@ func Test_e2e_converters(t *testing.T) {
 				tCtx.GetLogRecord().SetSpanID(pcommon.NewSpanIDEmpty())
 			},
 		},
+		{
+			statement: `set(span_id, SpanID("0102030405060708"))`,
+			want: func(tCtx *ottllog.TransformContext) {
+				tCtx.GetLogRecord().SetSpanID(pcommon.SpanID([8]byte{1, 2, 3, 4, 5, 6, 7, 8}))
+			},
+		},
 		{
 			statement: `set(attributes["test"], "pass") where String(ProfileID(0x00000000000000000000000000000001)) == "[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1]"`,
 			want: func(tCtx *ottllog.TransformContext) {
@@ -1167,6 +1173,12 @@ func Test_e2e_converters(t *testing.T) {
 				tCtx.GetLogRecord().SetTraceID(pcommon.NewTraceIDEmpty())
 			},
 		},
+		{
+			statement: `set(trace_id, TraceID("0102030405060708090a0b0c0d0e0f10"))`,
+			want: func(tCtx *ottllog.TransformContext) {
+				tCtx.GetLogRecord().SetTraceID(pcommon.TraceID([16]byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}))
+			},
+		},
 		{
 			statement: `set(time, TruncateTime(time, Duration("1s")))`,
 			want: func(tCtx *ottllog.TransformContext) {

pkg/ottl/e2e/profiles/e2e_test.go

@@ -1055,6 +1055,12 @@ func Test_e2e_converters(t *testing.T) {
 				tCtx.GetProfile().SetProfileID(pprofile.ProfileID{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0})
 			},
 		},
+		{
+			statement: `set(profile_id, ProfileID("0102030405060708090a0b0c0d0e0f10"))`,
+			want: func(_ *testing.T, tCtx ottlprofile.TransformContext) {
+				tCtx.GetProfile().SetProfileID(pprofile.ProfileID{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16})
+			},
+		},
 		{
 			statement: `set(attributes["test"], Split(attributes["flags"], "|"))`,
 			want: func(_ *testing.T, tCtx ottlprofile.TransformContext) {

pkg/ottl/ottlfuncs/README.md

@@ -1897,15 +1897,17 @@ Examples:
 
 ### ProfileID
 
-`ProfileID(bytes)`
+`ProfileID(bytes|string)`
 
-The `ProfileID` Converter returns a `pprofile.ProfileID` struct from the given byte slice.
+The `ProfileID` Converter returns a `pprofile.ProfileID` struct from the given byte slice OR hex string.
 
-`bytes` is a byte slice of exactly 16 bytes.
+`bytes`  byte slice of exactly 16 bytes.
+`string` is a string of exactly 32 hex characters solely composed of valid hexadecimal chars.
 
 Examples:
 
 - `ProfileID(0x00112233445566778899aabbccddeeff)`
+- `ProfileID("a389023abaa839283293ed323892389d")`
 
 ### RemoveXML
 
@@ -2163,15 +2165,17 @@ Examples:
 
 ### SpanID
 
-`SpanID(bytes)`
+`SpanID(bytes|string)`
 
-The `SpanID` Converter returns a `pdata.SpanID` struct from the given byte slice.
+The `SpanID` Converter returns a `pdata.SpanID` struct from the given byte slice OR hex string.
 
-`bytes` is a byte slice of exactly 8 bytes.
+`bytes`  byte slice of exactly 8 bytes.
+`string` is a string of exactly 16 hex characters solely composed of valid hexadecimal chars.
 
 Examples:
 
 - `SpanID(0x0000000000000000)`
+- `SpanID("0102030405060708")`
 
 ### Split
 
@@ -2448,15 +2452,18 @@ Examples:
 
 ### TraceID
 
-`TraceID(bytes)`
+`TraceID(bytes|string)`
 
-The `TraceID` Converter returns a `pdata.TraceID` struct from the given byte slice.
+The `TraceID` Converter returns a `pdata.TraceID` struct from the given byte slice OR hex string.
 
-`bytes` is a byte slice of exactly 16 bytes.
+`bytes`  byte slice of exactly 16 bytes.
+`string` is a string of exactly 16 bytes solely composed of valid hexadecimal chars.
 
 Examples:
 
 - `TraceID(0x00000000000000000000000000000000)`
+- `TraceID("a389023abaa839283293ed323892389d")`
+
 
 ### TruncateTime
 

pkg/ottl/ottlfuncs/func_profile_id.go

@@ -4,21 +4,22 @@
 package ottlfuncs // import "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl/ottlfuncs"
 
 import (
-	"context"
+	"encoding/hex"
 	"errors"
-	"fmt"
 
 	"go.opentelemetry.io/collector/pdata/pprofile"
 
 	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl"
 )
 
+const profileIDFuncName = "ProfileID"
+
 type ProfileIDArguments[K any] struct {
-	Bytes []byte
+	Target ottl.ByteSliceLikeGetter[K]
 }
 
 func NewProfileIDFactory[K any]() ottl.Factory[K] {
-	return ottl.NewFactory("ProfileID", &ProfileIDArguments[K]{}, createProfileIDFunction[K])
+	return ottl.NewFactory(profileIDFuncName, &ProfileIDArguments[K]{}, createProfileIDFunction[K])
 }
 
 func createProfileIDFunction[K any](_ ottl.FunctionContext, oArgs ottl.Arguments) (ottl.ExprFunc[K], error) {
@@ -28,16 +29,17 @@ func createProfileIDFunction[K any](_ ottl.FunctionContext, oArgs ottl.Arguments
 		return nil, errors.New("ProfileIDFactory args must be of type *ProfileIDArguments[K]")
 	}
 
-	return profileID[K](args.Bytes)
+	return profileID[K](args.Target)
+}
+
+func profileID[K any](target ottl.ByteSliceLikeGetter[K]) (ottl.ExprFunc[K], error) {
+	return newIDExprFunc(profileIDFuncName, target, decodeHexToProfileID)
 }
 
-func profileID[K any](bytes []byte) (ottl.ExprFunc[K], error) {
-	id := pprofile.ProfileID{}
-	if len(bytes) != len(id) {
-		return nil, fmt.Errorf("profile ids must be %d bytes", len(id))
+func decodeHexToProfileID(b []byte) (pprofile.ProfileID, error) {
+	var id pprofile.ProfileID
+	if _, err := hex.Decode(id[:], b); err != nil {
+		return pprofile.ProfileID{}, err
 	}
-	copy(id[:], bytes)
-	return func(context.Context, K) (any, error) {
-		return id, nil
-	}, nil
+	return id, nil
 }

pkg/ottl/ottlfuncs/func_profile_id_test.go

@@ -6,61 +6,50 @@ package ottlfuncs
 import (
 	"testing"
 
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
 	"go.opentelemetry.io/collector/pdata/pprofile"
 )
 
 func Test_profileID(t *testing.T) {
-	tests := []struct {
-		name  string
-		bytes []byte
-		want  pprofile.ProfileID
-	}{
+	runIDSuccessTests(t, profileID[any], []idSuccessTestCase{
 		{
-			name:  "create profile id",
-			bytes: []byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16},
+			name:  "create profile id from 16 bytes",
+			value: []byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16},
 			want:  pprofile.ProfileID([16]byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}),
 		},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			exprFunc, err := profileID[any](tt.bytes)
-			require.NoError(t, err)
-			result, err := exprFunc(nil, nil)
-			require.NoError(t, err)
-			assert.Equal(t, tt.want, result)
-		})
-	}
+		{
+			name:  "create profile id from 32 hex chars",
+			value: []byte("0102030405060708090a0b0c0d0e0f10"),
+			want:  pprofile.ProfileID([16]byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}),
+		},
+	})
 }
 
 func Test_profileID_validation(t *testing.T) {
-	tests := []struct {
-		name  string
-		bytes []byte
-		err   string
-	}{
+	runIDErrorTests(t, profileID[any], profileIDFuncName, []idErrorTestCase{
 		{
 			name:  "nil profile id",
-			bytes: nil,
-			err:   "profile ids must be 16 bytes",
+			value: nil,
+			err:   errIDInvalidLength,
+		},
+		{
+			name:  "byte slice less than 16 (15)",
+			value: []byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15},
+			err:   errIDInvalidLength,
+		},
+		{
+			name:  "byte slice longer than 16 (17)",
+			value: []byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17},
+			err:   errIDInvalidLength,
 		},
 		{
-			name:  "byte slice less than 16",
-			bytes: []byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15},
-			err:   "profile ids must be 16 bytes",
+			name:  "byte slice longer than 32 (33)",
+			value: []byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33},
+			err:   errIDInvalidLength,
 		},
 		{
-			name:  "byte slice longer than 16",
-			bytes: []byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17},
-			err:   "profile ids must be 16 bytes",
+			name:  "invalid hex string",
+			value: []byte("ZZ02030405060708090a0b0c0d0e0f10"),
+			err:   errIDHexDecode,
 		},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			_, err := profileID[any](tt.bytes)
-			require.Error(t, err)
-			assert.ErrorContains(t, err, tt.err)
-		})
-	}
+	})
 }

pkg/ottl/ottlfuncs/func_span_id.go

@@ -4,20 +4,22 @@
 package ottlfuncs // import "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl/ottlfuncs"
 
 import (
-	"context"
+	"encoding/hex"
 	"errors"
 
 	"go.opentelemetry.io/collector/pdata/pcommon"
 
 	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl"
 )
 
+const spanIDFuncName = "SpanID"
+
 type SpanIDArguments[K any] struct {
-	Bytes []byte
+	Target ottl.ByteSliceLikeGetter[K]
 }
 
 func NewSpanIDFactory[K any]() ottl.Factory[K] {
-	return ottl.NewFactory("SpanID", &SpanIDArguments[K]{}, createSpanIDFunction[K])
+	return ottl.NewFactory(spanIDFuncName, &SpanIDArguments[K]{}, createSpanIDFunction[K])
 }
 
 func createSpanIDFunction[K any](_ ottl.FunctionContext, oArgs ottl.Arguments) (ottl.ExprFunc[K], error) {
@@ -27,17 +29,17 @@ func createSpanIDFunction[K any](_ ottl.FunctionContext, oArgs ottl.Arguments) (
 		return nil, errors.New("SpanIDFactory args must be of type *SpanIDArguments[K]")
 	}
 
-	return spanID[K](args.Bytes)
+	return spanID[K](args.Target)
+}
+
+func spanID[K any](target ottl.ByteSliceLikeGetter[K]) (ottl.ExprFunc[K], error) {
+	return newIDExprFunc(spanIDFuncName, target, decodeHexToSpanID)
 }
 
-func spanID[K any](bytes []byte) (ottl.ExprFunc[K], error) {
-	if len(bytes) != 8 {
-		return nil, errors.New("span ids must be 8 bytes")
+func decodeHexToSpanID(b []byte) (pcommon.SpanID, error) {
+	var id pcommon.SpanID
+	if _, err := hex.Decode(id[:], b); err != nil {
+		return pcommon.SpanID{}, err
 	}
-	var idArr [8]byte
-	copy(idArr[:8], bytes)
-	id := pcommon.SpanID(idArr)
-	return func(context.Context, K) (any, error) {
-		return id, nil
-	}, nil
+	return id, nil
 }