Extract db.namespace from DSN in AttributesFromDSN

CHANGELOG.md

@@ -8,6 +8,10 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 ## [Unreleased]
 
+### Added
+
+- `AttributesFromDSN` now extracts the database name from the DSN and sets it as the `db.namespace` attribute ([`semconv.DBNamespaceKey`](https://opentelemetry.io/docs/specs/semconv/database/database-spans/#common-attributes)).
+
 ## [0.41.0] - 2025-12-16
 
 ### ⚠️ Notice ⚠️

Makefile

@@ -97,8 +97,14 @@ test-coverage:
 	  (cd "$${dir}" && \
 	    $(GO) list ./... \
 	    | grep -v third_party \
+	    | grep -v internal \
 	    | xargs $(GO) test -coverpkg=./... -covermode=$(COVERAGE_MODE) -coverprofile="$(COVERAGE_PROFILE)" && \
-	  $(GO) tool cover -html=coverage.out -o coverage.html); \
+	    $(GO) list ./... \
+	    | grep -v third_party \
+	    | grep internal \
+	    | xargs $(GO) test -coverpkg=$$($(GO) list ./... | grep internal | tr '\n' ',') -covermode=$(COVERAGE_MODE) -coverprofile="$(COVERAGE_PROFILE).internal" && \
+	    grep -v "^mode:" "$(COVERAGE_PROFILE).internal" >> "$(COVERAGE_PROFILE)" && \
+	  $(GO) tool cover -html=$(COVERAGE_PROFILE) -o coverage.html); \
 	  [ -f "$${dir}/coverage.out" ] && cat "$${dir}/coverage.out" >> coverage.txt; \
 	done; \
 	sed -i.bak -e '2,$$ { /^mode: /d; }' coverage.txt

helpers.go

@@ -24,61 +24,119 @@ import (
 )
 
 // AttributesFromDSN returns attributes extracted from a DSN string.
-// It makes the best effort to retrieve values for [semconv.ServerAddressKey] and [semconv.ServerPortKey].
+// It always sets [semconv.DBSystemNameKey], falling back to [semconv.DBSystemNameOtherSQL] when
+// the scheme is missing or unrecognized. It makes the best effort to retrieve values for
+// [semconv.ServerAddressKey], [semconv.ServerPortKey], and [semconv.DBNamespaceKey].
 func AttributesFromDSN(dsn string) []attribute.KeyValue {
-	// [scheme://][user[:password]@][protocol([addr])]/dbname[?param1=value1&paramN=valueN]
-	// Find the schema part.
-	schemaIndex := strings.Index(dsn, "://")
-	if schemaIndex != -1 {
-		// Remove the schema part from the DSN.
-		dsn = dsn[schemaIndex+3:]
+	scheme, serverAddress, serverPort, dbName := parseDSN(dsn)
+
+	var attrs []attribute.KeyValue
+
+	attrs = append(attrs, dbSystemFromScheme(scheme))
+
+	if serverAddress != "" {
+		attrs = append(attrs, semconv.ServerAddress(serverAddress))
+	}
+
+	if serverPort != -1 {
+		attrs = append(attrs, semconv.ServerPortKey.Int64(serverPort))
+	}
+
+	if dbName != "" {
+		attrs = append(attrs, semconv.DBNamespace(dbName))
+	}
+
+	return attrs
+}
+
+// dbSystemByScheme maps lowercase DSN schemes to their [semconv.DBSystemNameKey] attribute.
+var dbSystemByScheme = map[string]attribute.KeyValue{
+	"mysql":            semconv.DBSystemNameMySQL,
+	"postgres":         semconv.DBSystemNamePostgreSQL,
+	"postgresql":       semconv.DBSystemNamePostgreSQL,
+	"sqlserver":        semconv.DBSystemNameMicrosoftSQLServer,
+	"mssql":            semconv.DBSystemNameMicrosoftSQLServer,
+	"oracle":           semconv.DBSystemNameOracleDB,
+	"oracle+cx_oracle": semconv.DBSystemNameOracleDB,
+	"sqlite":           semconv.DBSystemNameSqlite,
+	"sqlite3":          semconv.DBSystemNameSqlite,
+	"mariadb":          semconv.DBSystemNameMariaDB,
+	"cockroachdb":      semconv.DBSystemNameCockroachdb,
+	"cockroach":        semconv.DBSystemNameCockroachdb,
+	"cassandra":        semconv.DBSystemNameCassandra,
+	"redis":            semconv.DBSystemNameRedis,
+	"rediss":           semconv.DBSystemNameRedis,
+	"mongodb":          semconv.DBSystemNameMongoDB,
+	"mongodb+srv":      semconv.DBSystemNameMongoDB,
+	"clickhouse":       semconv.DBSystemNameClickhouse,
+	"trino":            semconv.DBSystemNameTrino,
+	"hive":             semconv.DBSystemNameHive,
+	"spanner":          semconv.DBSystemNameGCPSpanner,
+	"elasticsearch":    semconv.DBSystemNameElasticsearch,
+	"couchbase":        semconv.DBSystemNameCouchbase,
+	"influxdb":         semconv.DBSystemNameInfluxdb,
+	"dynamodb":         semconv.DBSystemNameAWSDynamoDB,
+	"redshift":         semconv.DBSystemNameAWSRedshift,
+	"teradata":         semconv.DBSystemNameTeradata,
+	"firebird":         semconv.DBSystemNameFirebirdsql,
+	"firebirdsql":      semconv.DBSystemNameFirebirdsql,
+	"hbase":            semconv.DBSystemNameHBase,
+}
+
+// dbSystemFromScheme maps a DSN scheme to the corresponding [semconv.DBSystemNameKey] attribute.
+// It returns [semconv.DBSystemNameOtherSQL] if the scheme is not recognized or missing.
+func dbSystemFromScheme(scheme string) attribute.KeyValue {
+	if v, ok := dbSystemByScheme[strings.ToLower(scheme)]; ok {
+		return v
+	}
+
+	return semconv.DBSystemNameOtherSQL
+}
+
+// parseDSN parses a DSN string and returns the scheme, server address, server port, and database name.
+// It handles the format: [scheme://][user[:password]@][protocol([addr])]/dbname[?params]
+// scheme, serverAddress and dbName are empty strings if not found. serverPort is -1 if not found.
+func parseDSN(dsn string) (scheme, serverAddress string, serverPort int64, dbName string) {
+	serverPort = -1
+
+	if i := strings.Index(dsn, "://"); i != -1 {
+		scheme = dsn[:i]
+		dsn = dsn[i+3:]
 	}
 
-	// [user[:password]@][protocol([addr])]/dbname[?param1=value1&paramN=valueN]
-	// Find credentials part.
-	atIndex := strings.Index(dsn, "@")
-	if atIndex != -1 {
-		// Remove the credential part from the DSN.
-		dsn = dsn[atIndex+1:]
+	if i := strings.Index(dsn, "@"); i != -1 {
+		dsn = dsn[i+1:]
 	}
 
-	// [protocol([addr])]/dbname[?param1=value1&paramN=valueN]
-	// Find the '/' that separates the address part from the database part.
-	pathIndex := strings.Index(dsn, "/")
-	if pathIndex != -1 {
-		// Remove the path part from the DSN.
-		dsn = dsn[:pathIndex]
+	if i := strings.Index(dsn, "/"); i != -1 {
+		path := dsn[i+1:]
+		if j := strings.Index(path, "?"); j != -1 {
+			path = path[:j]
+		}
+
+		dbName = path
+		dsn = dsn[:i]
 	}
 
-	// [protocol([addr])] or [addr]
-	// Find the '(' that starts the address part.
-	openParen := strings.Index(dsn, "(")
-	if openParen != -1 {
-		// Remove the protocol part from the DSN.
-		dsn = dsn[openParen+1 : len(dsn)-1]
+	if i := strings.Index(dsn, "("); i != -1 {
+		dsn = dsn[i+1 : len(dsn)-1]
 	}
 
-	// [addr]
 	if len(dsn) == 0 {
-		return nil
+		return scheme, serverAddress, serverPort, dbName
 	}
 
 	host, portStr, err := net.SplitHostPort(dsn)
 	if err != nil {
-		host = dsn
+		serverAddress = dsn
+		return scheme, serverAddress, serverPort, dbName
 	}
 
-	attrs := make([]attribute.KeyValue, 0, 2)
-	if host != "" {
-		attrs = append(attrs, semconv.ServerAddress(host))
-	}
+	serverAddress = host
 
-	if portStr != "" {
-		port, err := strconv.ParseInt(portStr, 10, 64)
-		if err == nil {
-			attrs = append(attrs, semconv.ServerPortKey.Int64(port))
-		}
+	if port, err := strconv.ParseInt(portStr, 10, 64); err == nil {
+		serverPort = port
 	}
 
-	return attrs
+	return scheme, serverAddress, serverPort, dbName
 }