1 files changed, 51 insertions, 0 deletions
diff --git a/sqlr.go b/sqlr.go
new file mode 100644
index 0000000..0224c7c
--- /dev/null
+++ b/sqlr.go
@@ -0,0 +1,51 @@
+// Package sqlr ("squealer") provides some convenience wrappers around
+// database/sql in the spirit of encoding/json.
+package sqlr
+
+import (
+	"database/sql"
+	"fmt"
+	"reflect"
+)
+
+// Scan calls rows.Scan to unpack a single row into the fields of v.
+func Scan(rows *sql.Rows, v any) error {
+	rv := reflect.ValueOf(v)
+	if rv.Kind() != reflect.Pointer || rv.Elem().Kind() != reflect.Struct {
+		return fmt.Errorf("Scan needs a pointer to a struct")
+	}
+	inner := rv.Elem()
+	innerType := inner.Type()
+
+	fields := make(map[string]reflect.StructField)
+	inner.FieldByNameFunc(func(fieldName string) bool {
+		field, ok := innerType.FieldByName(fieldName)
+		if !ok {
+			return false
+		}
+		tag, ok := field.Tag.Lookup("sql")
+		if !ok {
+			fields[fieldName] = field
+			return false
+		}
+		if tag != "-" {
+			fields[tag] = field
+		}
+		return false
+	})
+
+	cols, err := rows.Columns()
+	if err != nil {
+		return err
+	}
+	dest := make([]any, len(cols))
+	for i, c := range cols {
+		field, ok := fields[c]
+		if !ok {
+			return fmt.Errorf("no field with tag %q", c)
+		}
+		dest[i] = inner.FieldByIndex(field.Index).Addr().Interface()
+	}
+
+	return rows.Scan(dest...)
+}