feat: add json_to_app method with support custom classes

idf_build_apps/main.py

@@ -1,4 +1,4 @@
-# SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
+# SPDX-FileCopyrightText: 2022-2024 Espressif Systems (Shanghai) CO LTD
 # SPDX-License-Identifier: Apache-2.0
 
 import argparse
@@ -11,6 +11,11 @@
 import textwrap
 import typing as t
 
+from pydantic import (
+    Field,
+    create_model,
+)
+
 from . import (
     SESSION_ARGS,
 )
@@ -45,6 +50,7 @@
     Manifest,
 )
 from .utils import (
+    BaseModel,
     InvalidCommand,
     files_matches_patterns,
     get_parallel_start_stop,
@@ -791,3 +797,46 @@ def main():
             print(f'  {app}')
 
     sys.exit(res)
+
+
+class AppDeserializer(BaseModel):
+    app: t.Union[App, CMakeApp, MakeApp] = Field(discriminator='build_system')
+
+    @classmethod
+    def from_json(cls, json_data: t.Union[str, bytes, bytearray]) -> App:
+        json_dict = json.loads(json_data.strip())
+        return cls.model_validate({'app': json_dict}).app
+
+
+def json_to_app(json_str: str, extra_classes: t.Optional[t.List[t.Type[App]]] = None) -> App:
+    """
+    Deserialize json string to App object
+
+    .. note::
+
+        You can pass extra_cls to support custom App class. A custom App class must be a subclass of App, and have a
+        different value of `build_system`. For example, a custom CMake app
+
+        >>> class CustomApp(CMakeApp):
+        >>>    build_system: Literal['custom_cmake'] = 'custom_cmake'
+
+        Then you can pass the CustomApp class to the `extra_cls` argument
+
+        >>> json_str = CustomApp('.', 'esp32').to_json()
+        >>> json_to_app(json_str, extra_classes=[CustomApp])
+
+    :param json_str: json string
+    :param extra_classes: extra App class
+    :return: App object
+    """
+    types = [App, CMakeApp, MakeApp]
+    if extra_classes:
+        types.extend(extra_classes)
+
+    custom_deserializer = create_model(
+        '_CustomDeserializer',
+        app=(t.Union[tuple(types)], Field(discriminator='build_system')),
+        __base__=AppDeserializer,
+    )
+
+    return custom_deserializer.from_json(json_str)

tests/test_app.py

@@ -1,13 +1,30 @@
 # SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
 # SPDX-License-Identifier: Apache-2.0
 
+import sys
+
 import pytest
+from pydantic import (
+    ValidationError,
+)
 
 from idf_build_apps import (
     AppDeserializer,
     CMakeApp,
     MakeApp,
 )
+from idf_build_apps.main import (
+    json_to_app,
+)
+
+if sys.version_info < (3, 8):
+    from typing_extensions import (
+        Literal,
+    )
+else:
+    from typing import (
+        Literal,
+    )
 
 
 def test_serialization():
@@ -54,3 +71,25 @@ def test_app_sorting():
     assert d == e
     assert not d < e
     assert not d > e
+
+
+def test_app_deserializer():
+    a = CMakeApp('foo', 'esp32')
+    b = MakeApp('foo', 'esp32')
+
+    class CustomApp(CMakeApp):
+        build_system: Literal['custom'] = 'custom'  # type: ignore
+
+    c = CustomApp('foo', 'esp32')
+
+    assert json_to_app(a.to_json()) == a
+    assert json_to_app(b.to_json()) == b
+
+    with pytest.raises(
+        ValidationError,
+        match="Input tag 'custom' found using 'build_system' does not match "
+        "any of the expected tags: 'unknown', 'cmake', 'make'",
+    ):
+        assert json_to_app(c.to_json()) == c
+
+    assert json_to_app(c.to_json(), extra_classes=[CustomApp]) == c