fix(otelsql): record error and status when SQL returns an error

The Span ends early when SQL returns an error, which prevents Otelsql from recording the error.
This commit fixes this issue by deferring the Span.End() call.

Fixes: #115

otelsql/internal/e2e_test.go

@@ -15,6 +15,7 @@ import (
 	_ "modernc.org/sqlite"
 
 	"github.com/uptrace/opentelemetry-go-extra/otelsql"
+	"go.opentelemetry.io/otel/codes"
 )
 
 var dbRowsAffected = attribute.Key("db.rows_affected")
@@ -159,6 +160,40 @@ func TestConn(t *testing.T) {
 				}
 			},
 		},
+		{
+			do: func(ctx context.Context, db *sql.DB) {
+				_, err := db.ExecContext(ctx, "SELECT 1 FROM ABC")
+				require.Error(t, err)
+			},
+			require: func(t *testing.T, spans []sdktrace.ReadOnlySpan) {
+				require.Equal(t, 2, len(spans))
+				require.Equal(t, "db.Connect", spans[0].Name())
+				require.Equal(t, "db.Exec", spans[1].Name())
+
+				span := spans[1]
+				require.Equal(t, "db.Exec", span.Name())
+
+				m := attrMap(span.Attributes())
+
+				stmt, ok := m[semconv.DBStatementKey]
+				require.True(t, ok)
+				require.Equal(t, "SELECT 1 FROM ABC", stmt.AsString())
+
+				status := span.Status()
+				require.Equal(t, codes.Error, status.Code)
+				require.Equal(t, "SQL logic error: no such table: ABC (1)", status.Description)
+
+				e := eventAttrsMap(span.Events())
+
+				key, ok := e[semconv.ExceptionTypeKey]
+				require.True(t, ok)
+				require.Equal(t, "*sqlite.Error", key.AsString())
+
+				message, ok := e[semconv.ExceptionMessageKey]
+				require.True(t, ok)
+				require.Equal(t, "SQL logic error: no such table: ABC (1)", message.AsString())
+			},
+		},
 	}
 
 	for i, test := range tests {
@@ -188,3 +223,14 @@ func attrMap(attrs []attribute.KeyValue) map[attribute.Key]attribute.Value {
 	}
 	return m
 }
+
+func eventAttrsMap(events []sdktrace.Event) map[attribute.Key]attribute.Value {
+	m := make(map[attribute.Key]attribute.Value, len(events))
+	for _, event := range events {
+		for _, kv := range event.Attributes {
+			m[kv.Key] = kv.Value
+		}
+	}
+
+	return m
+}

otelsql/otel.go

@@ -101,7 +101,7 @@ func (t *dbInstrum) withSpan(
 		trace.WithSpanKind(trace.SpanKindClient),
 		trace.WithAttributes(attrs...))
 	err := fn(ctx, span)
-	span.End()
+	defer span.End()
 
 	if query != "" {
 		t.queryHistogram.Record(ctx, time.Since(startTime).Milliseconds(), metric.WithAttributes(t.attrs...))