add code attributes to semconv package (#1558)

* add code attributes to semconv package

* update changelog

* update comment for code semconv attributes

Adds a full-stop at the end of the comment.

Co-authored-by: Anthony Mirabella <a9@aneurysm9.com>
Co-authored-by: Tyler Yahn <MrAlias@users.noreply.github.com>

CHANGELOG.md

@@ -25,6 +25,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 - Added `resource.Default()` for use with meter and tracer providers. (#1507)
 - Added `Keys()` method to `propagation.TextMapCarrier` and `propagation.HeaderCarrier` to adapt `http.Header` to this interface. (#1544)
+- Added `code` attributes to `go.opentelemetry.io/otel/semconv` package. (#1558)
 
 ### Removed
 

semconv/trace.go

@@ -353,3 +353,24 @@ var (
 	FaaSDocumentOperationEdit   = FaaSDocumentOperationKey.String("edit")
 	FaaSDocumentOperationDelete = FaaSDocumentOperationKey.String("delete")
 )
+
+// Semantic conventions for source code attributes.
+const (
+	// The method or function name, or equivalent (usually rightmost part of
+	// the code unit's name).
+	CodeFunctionKey = attribute.Key("code.function")
+
+	// The "namespace" within which `code.function` is defined. Usually the
+	// qualified class or module name, such that
+	// `code.namespace` + some separator + `code.function` form a unique
+	// identifier for the code unit.
+	CodeNamespaceKey = attribute.Key("code.namespace")
+
+	// The source code file name that identifies the code unit as uniquely as
+	// possible (preferably an absolute file path).
+	CodeFilepathKey = attribute.Key("code.filepath")
+
+	// The line number in `code.filepath` best representing the operation.
+	// It SHOULD point within the code unit named in `code.function`.
+	CodeLineNumberKey = attribute.Key("code.lineno")
+)