[pkg/ottl] Add OTTL support for profiles (open-telemetry#37574)

Fixes
open-telemetry#36104

This is a first PR to get profiles support into OTTL. Follow-up PRs will
add support for more sub-types of profiles like `sample`, `mapping`
etc..

Author: rockdaboot

.chloggen/ottl-profile.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: ottlprofile
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add OTTL support for profiles.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [36104]
+
+# (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: []

pkg/ottl/contexts/internal/ctxcommon/ids.go

@@ -8,6 +8,7 @@ import (
 	"errors"
 
 	"go.opentelemetry.io/collector/pdata/pcommon"
+	"go.opentelemetry.io/collector/pdata/pprofile"
 )
 
 func ParseSpanID(spanIDStr string) (pcommon.SpanID, error) {
@@ -33,3 +34,15 @@ func ParseTraceID(traceIDStr string) (pcommon.TraceID, error) {
 	}
 	return id, nil
 }
+
+func ParseProfileID(profileIDStr string) (pprofile.ProfileID, error) {
+	var id pprofile.ProfileID
+	if hex.DecodedLen(len(profileIDStr)) != len(id) {
+		return pprofile.ProfileID{}, errors.New("profile ids must be 32 hex characters")
+	}
+	_, err := hex.Decode(id[:], []byte(profileIDStr))
+	if err != nil {
+		return pprofile.ProfileID{}, err
+	}
+	return id, nil
+}

pkg/ottl/contexts/internal/ctxcommon/ids_test.go

@@ -60,3 +60,28 @@ func TestParseTraceIDError(t *testing.T) {
 		})
 	}
 }
+
+func TestParseProfileIDError(t *testing.T) {
+	tests := []struct {
+		name    string
+		input   string
+		wantErr string
+	}{
+		{
+			name:    "incorrect size",
+			input:   "0123456789abcdef0123456789abcde",
+			wantErr: "profile ids must be 32 hex characters",
+		},
+		{
+			name:    "incorrect characters",
+			input:   "0123456789Xbcdef0123456789abcdef",
+			wantErr: "encoding/hex: invalid byte: U+0058 'X'",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := ctxcommon.ParseProfileID(tt.input)
+			assert.EqualError(t, err, tt.wantErr)
+		})
+	}
+}

pkg/ottl/contexts/internal/ctxprofile/context.go

@@ -0,0 +1,16 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package ctxprofile // import "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl/contexts/internal/ctxprofile"
+import (
+	"go.opentelemetry.io/collector/pdata/pprofile"
+)
+
+const (
+	Name   = "profile"
+	DocRef = "https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/pkg/ottl/contexts/ottlprofile"
+)
+
+type Context interface {
+	GetProfile() pprofile.Profile
+}