1 files changed, 81 insertions, 0 deletions
diff --git a/python/knot_resolver/client/commands/convert.py b/python/knot_resolver/client/commands/convert.py
new file mode 100644
index 00000000..412ed334
--- /dev/null
+++ b/python/knot_resolver/client/commands/convert.py
@@ -0,0 +1,81 @@
+import argparse
+import sys
+from pathlib import Path
+from typing import List, Optional, Tuple, Type
+
+from knot_resolver.client.command import Command, CommandArgs, CompWords, register_command
+from knot_resolver.datamodel import KresConfig
+from knot_resolver.datamodel.globals import Context, reset_global_validation_context, set_global_validation_context
+from knot_resolver.utils.modeling import try_to_parse
+from knot_resolver.utils.modeling.exceptions import DataParsingError, DataValidationError
+
+
+@register_command
+class ConvertCommand(Command):
+    def __init__(self, namespace: argparse.Namespace) -> None:
+        super().__init__(namespace)
+        self.input_file: str = namespace.input_file
+        self.output_file: Optional[str] = namespace.output_file
+        self.strict: bool = namespace.strict
+        self.type: str = namespace.type
+
+    @staticmethod
+    def register_args_subparser(
+        subparser: "argparse._SubParsersAction[argparse.ArgumentParser]",
+    ) -> Tuple[argparse.ArgumentParser, "Type[Command]"]:
+        convert = subparser.add_parser("convert", help="Converts JSON or YAML configuration to Lua script.")
+        convert.set_defaults(strict=True)
+        convert.add_argument(
+            "--no-strict",
+            help="Ignore strict rules during validation, e.g. path/file existence.",
+            action="store_false",
+            dest="strict",
+        )
+        convert.add_argument(
+            "--type", help="The type of Lua script to generate", choices=["worker", "policy-loader"], default="worker"
+        )
+        convert.add_argument(
+            "input_file",
+            type=str,
+            help="File with configuration in YAML or JSON format.",
+        )
+
+        convert.add_argument(
+            "output_file",
+            type=str,
+            nargs="?",
+            help="Optional, output file for converted configuration in Lua script. If not specified, converted configuration is printed.",
+            default=None,
+        )
+
+        return convert, ConvertCommand
+
+    @staticmethod
+    def completion(args: List[str], parser: argparse.ArgumentParser) -> CompWords:
+        return {}
+
+    def run(self, args: CommandArgs) -> None:
+        with open(self.input_file, "r") as f:
+            data = f.read()
+
+        try:
+            parsed = try_to_parse(data)
+            set_global_validation_context(Context(Path(Path(self.input_file).parent), self.strict))
+
+            if self.type == "worker":
+                lua = KresConfig(parsed).render_lua()
+            elif self.type == "policy-loader":
+                lua = KresConfig(parsed).render_lua_policy()
+            else:
+                raise ValueError(f"Invalid self.type={self.type}")
+
+            reset_global_validation_context()
+        except (DataParsingError, DataValidationError) as e:
+            print(e, file=sys.stderr)
+            sys.exit(1)
+
+        if self.output_file:
+            with open(self.output_file, "w") as f:
+                f.write(lua)
+        else:
+            print(lua)