From 401342ab9c72349cc3b2148110ab33f715bf1e1f Mon Sep 17 00:00:00 2001
From: Fu Hanxi <fuhanxi@espressif.com>
Date: Fri, 5 Jan 2024 11:02:40 +0100
Subject: [PATCH] feat: add `json_to_app` method with support custom classes

---
 idf_build_apps/__init__.py |  5 +++--
 idf_build_apps/app.py      |  5 ++---
 idf_build_apps/main.py     | 42 +++++++++++++++++++++++++++++++++++++-
 tests/test_app.py          | 39 +++++++++++++++++++++++++++++++++++
 4 files changed, 85 insertions(+), 6 deletions(-)

diff --git a/idf_build_apps/__init__.py b/idf_build_apps/__init__.py
index 2a31ffe..cc5ae7c 100644
--- a/idf_build_apps/__init__.py
+++ b/idf_build_apps/__init__.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
 
 """
@@ -28,6 +28,7 @@
 from .main import (
     build_apps,
     find_apps,
+    json_to_app,
 )
 
 __all__ = [
@@ -37,6 +38,6 @@
     'MakeApp',
     'find_apps',
     'build_apps',
+    'json_to_app',
     'setup_logging',
-    'SESSION_ARGS',
 ]
diff --git a/idf_build_apps/app.py b/idf_build_apps/app.py
index 68a6d87..8866ae5 100644
--- a/idf_build_apps/app.py
+++ b/idf_build_apps/app.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 functools
@@ -25,10 +25,9 @@
     computed_field,
 )
 
-from idf_build_apps import (
+from . import (
     SESSION_ARGS,
 )
-
 from .build_apps_args import (
     BuildAppsArgs,
 )
diff --git a/idf_build_apps/main.py b/idf_build_apps/main.py
index b9544b4..c5c738b 100644
--- a/idf_build_apps/main.py
+++ b/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
@@ -11,11 +11,17 @@
 import textwrap
 import typing as t
 
+from pydantic import (
+    Field,
+    create_model,
+)
+
 from . import (
     SESSION_ARGS,
 )
 from .app import (
     App,
+    AppDeserializer,
     CMakeApp,
     MakeApp,
 )
@@ -791,3 +797,37 @@ def main():
             print(f'  {app}')
 
     sys.exit(res)
+
+
+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)
diff --git a/tests/test_app.py b/tests/test_app.py
index 77e81d3..22f2c7d 100644
--- a/tests/test_app.py
+++ b/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