Create JsonConfigLoader.

This CL adds a JsonConfigLoader to parse the vehicle proeprty
config file in JSON format.

This CL also adds DefaultConfigTest to verify the JSON file
is compatible with the existing header file.

Test: atest JsonConfigLoaderUnitTest
atest VehicleHalDefaultConfigTest
Bug: 238685398

Change-Id: If679afd2245cb7e2a49fd964f343b660c9bcea25
diff --git a/automotive/vehicle/TEST_MAPPING b/automotive/vehicle/TEST_MAPPING
index fa0b791..da8416c 100644
--- a/automotive/vehicle/TEST_MAPPING
+++ b/automotive/vehicle/TEST_MAPPING
@@ -7,6 +7,15 @@
       "name": "VehicleHalDefaultConfigTest"
     },
     {
+      "name": "VehicleHalDefaultConfigTestEnableTestProperties"
+    },
+    {
+      "name": "JsonConfigLoaderUnitTest"
+    },
+    {
+      "name": "JsonConfigLoaderUnitTestEnableTestProperties"
+    },
+    {
       "name": "VehicleHalVehicleUtilsTest"
     },
     {
diff --git a/automotive/vehicle/aidl/impl/default_config/Android.bp b/automotive/vehicle/aidl/impl/default_config/Android.bp
index 0feaf23..aa22d87 100644
--- a/automotive/vehicle/aidl/impl/default_config/Android.bp
+++ b/automotive/vehicle/aidl/impl/default_config/Android.bp
@@ -25,7 +25,13 @@
     export_include_dirs: ["include"],
     defaults: ["VehicleHalDefaults"],
     static_libs: ["VehicleHalUtils"],
-    header_libs: ["VehicleHalTestUtilHeaders"],
+    header_libs: [
+        "VehicleHalJsonConfigLoaderHeaders",
+        "VehicleHalTestUtilHeaders",
+    ],
     export_static_lib_headers: ["VehicleHalUtils"],
-    export_header_lib_headers: ["VehicleHalTestUtilHeaders"],
+    export_header_lib_headers: [
+        "VehicleHalTestUtilHeaders",
+        "VehicleHalJsonConfigLoaderHeaders",
+    ],
 }
diff --git a/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/Android.bp b/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/Android.bp
new file mode 100644
index 0000000..6984d5e
--- /dev/null
+++ b/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/Android.bp
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+cc_library {
+    name: "VehicleHalJsonConfigLoader",
+    vendor: true,
+    srcs: ["src/*.cpp"],
+    local_include_dirs: ["include"],
+    export_include_dirs: ["include"],
+    defaults: ["VehicleHalDefaults"],
+    static_libs: ["VehicleHalUtils"],
+    header_libs: [
+        "IVehicleGeneratedHeaders",
+    ],
+    shared_libs: ["libjsoncpp"],
+}
+
+cc_library {
+    name: "VehicleHalJsonConfigLoaderEnableTestProperties",
+    vendor: true,
+    srcs: ["src/*.cpp"],
+    local_include_dirs: ["include"],
+    export_include_dirs: ["include"],
+    defaults: ["VehicleHalDefaults"],
+    static_libs: ["VehicleHalUtils"],
+    header_libs: [
+        "VehicleHalTestUtilHeaders",
+        "IVehicleGeneratedHeaders",
+    ],
+    cflags: ["-DENABLE_VEHICLE_HAL_TEST_PROPERTIES"],
+    shared_libs: ["libjsoncpp"],
+}
+
+cc_library_headers {
+    name: "VehicleHalJsonConfigLoaderHeaders",
+    vendor: true,
+    local_include_dirs: ["include"],
+    export_include_dirs: ["include"],
+    defaults: ["VehicleHalDefaults"],
+    static_libs: ["VehicleHalUtils"],
+    header_libs: [
+        "IVehicleGeneratedHeaders",
+    ],
+    shared_libs: ["libjsoncpp"],
+}
diff --git a/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/include/ConfigDeclaration.h b/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/include/ConfigDeclaration.h
new file mode 100644
index 0000000..40ac129
--- /dev/null
+++ b/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/include/ConfigDeclaration.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef android_hardware_automotive_vehicle_aidl_impl_default_config_JsonConfigLoader_include_ConfigDeclaration_H_
+#define android_hardware_automotive_vehicle_aidl_impl_default_config_JsonConfigLoader_include_ConfigDeclaration_H_
+
+#include <VehicleHalTypes.h>
+
+#include <unordered_map>
+
+namespace android {
+namespace hardware {
+namespace automotive {
+namespace vehicle {
+
+// ConfigDeclaration represents one property config, its optional initial value and its optional
+// area configs and initial values for each area.
+struct ConfigDeclaration {
+    aidl::android::hardware::automotive::vehicle::VehiclePropConfig config;
+
+    // This value will be used as an initial value for the property. If this field is specified for
+    // property that supports multiple areas then it will be used for all areas unless particular
+    // area is overridden in initialAreaValue field.
+    aidl::android::hardware::automotive::vehicle::RawPropValues initialValue;
+    // Use initialAreaValues if it is necessary to specify different values per each area.
+    std::unordered_map<int32_t, aidl::android::hardware::automotive::vehicle::RawPropValues>
+            initialAreaValues;
+
+    inline bool operator==(const ConfigDeclaration& other) const {
+        return (config == other.config && initialValue == other.initialValue &&
+                initialAreaValues == other.initialAreaValues);
+    }
+
+    friend std::ostream& operator<<(std::ostream& os, const ConfigDeclaration& c) {
+        return os << "Config Declaration for property: "
+                  << aidl::android::hardware::automotive::vehicle::toString(
+                             static_cast<
+                                     aidl::android::hardware::automotive::vehicle::VehicleProperty>(
+                                     c.config.prop));
+    }
+};
+
+}  // namespace vehicle
+}  // namespace automotive
+}  // namespace hardware
+}  // namespace android
+
+#endif  // android_hardware_automotive_vehicle_aidl_impl_default_config_JsonConfigLoader_include_ConfigDeclaration_H_
diff --git a/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/include/JsonConfigLoader.h b/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/include/JsonConfigLoader.h
new file mode 100644
index 0000000..a6e59e6
--- /dev/null
+++ b/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/include/JsonConfigLoader.h
@@ -0,0 +1,132 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef android_hardware_automotive_vehicle_aidl_impl_default_config_JsonConfigLoader_include_JsonConfigLoader_H_
+#define android_hardware_automotive_vehicle_aidl_impl_default_config_JsonConfigLoader_include_JsonConfigLoader_H_
+
+#include <ConfigDeclaration.h>
+#include <VehicleHalTypes.h>
+
+#include <android-base/result.h>
+#include <json/json.h>
+#include <unordered_map>
+#include <utility>
+#include <vector>
+
+namespace android {
+namespace hardware {
+namespace automotive {
+namespace vehicle {
+
+// private namespace
+namespace jsonconfigloader_impl {
+
+// A class to parse a value field in JSON config file.
+// If the field is a string and the field is in the format of "XX::XX", the value will be parsed
+// as a constant value in the format of "TYPE::NAME". Otherwise, the field will be return as is
+// converted to the expected type.
+class JsonValueParser final {
+  public:
+    JsonValueParser();
+
+    android::base::Result<std::string> parseStringValue(const std::string& fieldName,
+                                                        const Json::Value& value) const;
+
+    template <class T>
+    android::base::Result<std::vector<T>> parseArray(const std::string& fieldName,
+                                                     const Json::Value& value) const;
+
+    template <class T>
+    android::base::Result<T> parseValue(const std::string& fieldName,
+                                        const Json::Value& value) const;
+
+  private:
+    template <class T>
+    static android::base::Result<T> convertValueToType(const std::string& fieldName,
+                                                       const Json::Value& value);
+
+    std::optional<std::pair<std::string, std::string>> maybeGetTypeAndValueName(
+            const std::string& jsonFieldValue) const;
+};
+
+// The main class to parse a VHAL config file in JSON format.
+class JsonConfigParser {
+  public:
+    android::base::Result<std::vector<ConfigDeclaration>> parseJsonConfig(std::istream& is);
+
+  private:
+    JsonValueParser mValueParser;
+
+    // Parses configuration for each property.
+    std::optional<ConfigDeclaration> parseEachProperty(const Json::Value& propJsonValue,
+                                                       std::vector<std::string>* errors);
+    // Tries to parse a JSON value to a specific type.
+    //
+    // If fieldIsOptional is True, then if the field specified by "fieldName" does not exist,
+    // this method will return true without doing anything, otherwise, it will return false.
+    //
+    // @param parentJsonNode The parent node of the field you are going to parse.
+    // @param fieldName The name for the field.
+    // @param fieldIsOptional Whether the field is optional.
+    // @param outPtr The pointer to output to if the field exists and parsing succeeded.
+    // @param errors The error array to append error to if errors are found.
+    // @return true if the field is optional and does not exist or parsed successfully.
+    template <class T>
+    bool tryParseJsonValueToVariable(const Json::Value& parentJsonNode,
+                                     const std::string& fieldName, bool fieldIsOptional, T* outPtr,
+                                     std::vector<std::string>* errors);
+    // Tries to parse a JSON value to an array of specific type.
+    //
+    // If fieldIsOptional is True, then if the field specified by "fieldName" does not exist,
+    // this method will return true without doing anything, otherwise, it will return false.
+    //
+    // @param parentJsonNode The parent node of the field you are going to parse.
+    // @param fieldName The name for the field.
+    // @param fieldIsOptional Whether the field is optional.
+    // @param outPtr The pointer to output to if the field exists and parsing succeeded.
+    // @param errors The error array to append error to if errors are found.
+    // @return true if the field is optional and does not exist or parsed successfully.
+    template <class T>
+    bool tryParseJsonArrayToVariable(const Json::Value& parentJsonNode,
+                                     const std::string& fieldName, bool fieldIsOptional,
+                                     std::vector<T>* outPtr, std::vector<std::string>* errors);
+
+    // Parses a JSON field to RawPropValues.
+    void parsePropValues(const Json::Value& parentJsonNode, const std::string& fieldName,
+                         aidl::android::hardware::automotive::vehicle::RawPropValues* outPtr,
+                         std::vector<std::string>* errors);
+};
+
+}  // namespace jsonconfigloader_impl
+
+// A class to load vehicle property configs and initial values in JSON format.
+class JsonConfigLoader final {
+  public:
+    JsonConfigLoader();
+
+    // Loads a JSON file stream and parses it to a list of ConfigDeclarations.
+    android::base::Result<std::vector<ConfigDeclaration>> loadPropConfig(std::istream& is);
+
+  private:
+    std::unique_ptr<jsonconfigloader_impl::JsonConfigParser> mParser;
+};
+
+}  // namespace vehicle
+}  // namespace automotive
+}  // namespace hardware
+}  // namespace android
+
+#endif  // android_hardware_automotive_vehicle_aidl_impl_default_config_JsonConfigLoader_include_JsonConfigLoader_H_
diff --git a/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/src/JsonConfigLoader.cpp b/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/src/JsonConfigLoader.cpp
new file mode 100644
index 0000000..c569b33
--- /dev/null
+++ b/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/src/JsonConfigLoader.cpp
@@ -0,0 +1,315 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <JsonConfigLoader.h>
+
+#include <AccessForVehicleProperty.h>
+#include <ChangeModeForVehicleProperty.h>
+#include <PropertyUtils.h>
+
+#ifdef ENABLE_VEHICLE_HAL_TEST_PROPERTIES
+#include <TestPropertyUtils.h>
+#endif  // ENABLE_VEHICLE_HAL_TEST_PROPERTIES
+
+#include <android-base/strings.h>
+
+namespace android {
+namespace hardware {
+namespace automotive {
+namespace vehicle {
+
+namespace jsonconfigloader_impl {
+
+using ::aidl::android::hardware::automotive::vehicle::AccessForVehicleProperty;
+using ::aidl::android::hardware::automotive::vehicle::ChangeModeForVehicleProperty;
+using ::aidl::android::hardware::automotive::vehicle::EvConnectorType;
+using ::aidl::android::hardware::automotive::vehicle::EvsServiceState;
+using ::aidl::android::hardware::automotive::vehicle::EvsServiceType;
+using ::aidl::android::hardware::automotive::vehicle::FuelType;
+using ::aidl::android::hardware::automotive::vehicle::GsrComplianceRequirementType;
+using ::aidl::android::hardware::automotive::vehicle::RawPropValues;
+using ::aidl::android::hardware::automotive::vehicle::VehicleApPowerStateReport;
+using ::aidl::android::hardware::automotive::vehicle::VehicleApPowerStateReq;
+using ::aidl::android::hardware::automotive::vehicle::VehicleAreaConfig;
+using ::aidl::android::hardware::automotive::vehicle::VehicleAreaWindow;
+using ::aidl::android::hardware::automotive::vehicle::VehicleGear;
+using ::aidl::android::hardware::automotive::vehicle::VehicleHvacFanDirection;
+using ::aidl::android::hardware::automotive::vehicle::VehicleIgnitionState;
+using ::aidl::android::hardware::automotive::vehicle::VehicleOilLevel;
+using ::aidl::android::hardware::automotive::vehicle::VehiclePropConfig;
+using ::aidl::android::hardware::automotive::vehicle::VehicleProperty;
+using ::aidl::android::hardware::automotive::vehicle::VehiclePropertyAccess;
+using ::aidl::android::hardware::automotive::vehicle::VehiclePropertyChangeMode;
+using ::aidl::android::hardware::automotive::vehicle::VehicleSeatOccupancyState;
+using ::aidl::android::hardware::automotive::vehicle::VehicleTurnSignal;
+using ::aidl::android::hardware::automotive::vehicle::VehicleUnit;
+using ::aidl::android::hardware::automotive::vehicle::VehicleVendorPermission;
+
+using ::android::base::Error;
+using ::android::base::Result;
+
+template <>
+Result<int32_t> JsonValueParser::convertValueToType<int32_t>(const std::string& fieldName,
+                                                             const Json::Value& value) {
+    if (!value.isInt()) {
+        return Error() << "The value: " << value << " for field: " << fieldName
+                       << " is not in correct type, expect int";
+    }
+    return static_cast<int32_t>(value.asInt());
+}
+
+template <>
+Result<float> JsonValueParser::convertValueToType<float>(const std::string& fieldName,
+                                                         const Json::Value& value) {
+    // isFloat value does not exist, so we use isDouble here.
+    if (!value.isDouble()) {
+        return Error() << "The value: " << value << " for field: " << fieldName
+                       << " is not in correct type, expect float";
+    }
+    return value.asFloat();
+}
+
+template <>
+Result<int64_t> JsonValueParser::convertValueToType<int64_t>(const std::string& fieldName,
+                                                             const Json::Value& value) {
+    if (!value.isInt64()) {
+        return Error() << "The value: " << value << " for field: " << fieldName
+                       << " is not in correct type, expect int64";
+    }
+    return static_cast<int64_t>(value.asInt64());
+}
+
+template <>
+Result<std::string> JsonValueParser::convertValueToType<std::string>(const std::string& fieldName,
+                                                                     const Json::Value& value) {
+    if (!value.isString()) {
+        return Error() << "The value: " << value << " for field: " << fieldName
+                       << " is not in correct type, expect string";
+    }
+    return value.asString();
+}
+
+Result<std::string> JsonValueParser::parseStringValue(const std::string& fieldName,
+                                                      const Json::Value& value) const {
+    return convertValueToType<std::string>(fieldName, value);
+}
+
+template <class T>
+Result<T> JsonValueParser::parseValue(const std::string& fieldName,
+                                      const Json::Value& value) const {
+    if (!value.isString()) {
+        return convertValueToType<T>(fieldName, value);
+    }
+    auto maybeTypeAndValue = maybeGetTypeAndValueName(value.asString());
+    if (!maybeTypeAndValue.has_value()) {
+        return Error() << "Invalid constant value: " << value << " for field: " << fieldName;
+    }
+    auto constantParseResult = parseConstantValue(maybeTypeAndValue.value());
+    if (!constantParseResult.ok()) {
+        return constantParseResult.error();
+    }
+    int constantValue = constantParseResult.value();
+    return static_cast<T>(constantValue);
+}
+
+template <>
+Result<std::string> JsonValueParser::parseValue<std::string>(const std::string& fieldName,
+                                                             const Json::Value& value) const {
+    return parseStringValue(fieldName, value);
+}
+
+template <class T>
+Result<std::vector<T>> JsonValueParser::parseArray(const std::string& fieldName,
+                                                   const Json::Value& value) const {
+    if (!value.isArray()) {
+        return Error() << "The value: " << value << " for field: " << fieldName
+                       << " is not in correct type, expect array";
+    }
+    std::vector<T> parsedValues;
+    for (unsigned int i = 0; i < value.size(); i++) {
+        auto result = parseValue<T>(fieldName, value[i]);
+        if (!result.ok()) {
+            return result.error();
+        }
+        parsedValues.push_back(result.value());
+    }
+    return std::move(parsedValues);
+}
+
+std::optional<std::pair<std::string, std::string>> JsonValueParser::maybeGetTypeAndValueName(
+        const std::string& jsonFieldValue) const {
+    size_t pos = jsonFieldValue.find(DELIMITER);
+    if (pos == std::string::npos) {
+        return {};
+    }
+    std::string type = jsonFieldValue.substr(0, pos);
+    std::string valueName = jsonFieldValue.substr(pos + DELIMITER.length(), std::string::npos);
+    return std::make_pair(type, valueName);
+}
+
+Result<int> JsonValueParser::parseConstantValue(const std::pair<std::string, std::string>&) const {
+    // TODO(b/238685398): Implement this.
+}
+
+template <class T>
+bool JsonConfigParser::tryParseJsonValueToVariable(const Json::Value& parentJsonNode,
+                                                   const std::string& fieldName,
+                                                   bool fieldIsOptional, T* outPtr,
+                                                   std::vector<std::string>* errors) {
+    if (!parentJsonNode.isObject()) {
+        errors->push_back("Node: " + parentJsonNode.toStyledString() + " is not an object");
+        return false;
+    }
+    if (!parentJsonNode.isMember(fieldName)) {
+        if (!fieldIsOptional) {
+            errors->push_back("Missing required field: " + fieldName +
+                              " in node: " + parentJsonNode.toStyledString());
+            return false;
+        }
+        return true;
+    }
+    auto result = mValueParser.parseValue<T>(fieldName, parentJsonNode[fieldName]);
+    if (!result.ok()) {
+        errors->push_back(result.error().message());
+        return false;
+    }
+    *outPtr = std::move(result.value());
+    return true;
+}
+
+template <class T>
+bool JsonConfigParser::tryParseJsonArrayToVariable(const Json::Value& parentJsonNode,
+                                                   const std::string& fieldName,
+                                                   bool fieldIsOptional, std::vector<T>* outPtr,
+                                                   std::vector<std::string>* errors) {
+    if (!parentJsonNode.isObject()) {
+        errors->push_back("Node: " + parentJsonNode.toStyledString() + " is not an object");
+        return false;
+    }
+    if (!parentJsonNode.isMember(fieldName)) {
+        if (!fieldIsOptional) {
+            errors->push_back("Missing required field: " + fieldName +
+                              " in node: " + parentJsonNode.toStyledString());
+            return false;
+        }
+        return true;
+    }
+    auto result = mValueParser.parseArray<T>(fieldName, parentJsonNode[fieldName]);
+    if (!result.ok()) {
+        errors->push_back(result.error().message());
+        return false;
+    }
+    *outPtr = std::move(result.value());
+    return true;
+}
+
+void JsonConfigParser::parsePropValues(const Json::Value& parentJsonNode,
+                                       const std::string& fieldName, RawPropValues* outPtr,
+                                       std::vector<std::string>* errors) {
+    if (!parentJsonNode.isObject()) {
+        errors->push_back("Node: " + parentJsonNode.toStyledString() + " is not an object");
+        return;
+    }
+    if (!parentJsonNode.isMember(fieldName)) {
+        return;
+    }
+    const Json::Value& jsonValue = parentJsonNode[fieldName];
+    tryParseJsonArrayToVariable(jsonValue, "int32Values", /*optional=*/true, &(outPtr->int32Values),
+                                errors);
+    tryParseJsonArrayToVariable(jsonValue, "floatValues", /*optional=*/true, &(outPtr->floatValues),
+                                errors);
+    tryParseJsonArrayToVariable(jsonValue, "int64Values", /*optional=*/true, &(outPtr->int64Values),
+                                errors);
+    // We don't support "byteValues" yet.
+    tryParseJsonValueToVariable(jsonValue, "stringValue", /*optional=*/true, &(outPtr->stringValue),
+                                errors);
+}
+
+std::optional<ConfigDeclaration> JsonConfigParser::parseEachProperty(
+        const Json::Value& propJsonValue, std::vector<std::string>* errors) {
+    size_t initialErrorCount = errors->size();
+    ConfigDeclaration configDecl = {};
+    int32_t propId;
+
+    if (!tryParseJsonValueToVariable(propJsonValue, "property", /*optional=*/false, &propId,
+                                     errors)) {
+        return std::nullopt;
+    }
+
+    configDecl.config.prop = propId;
+    std::string propStr = propJsonValue["property"].toStyledString();
+
+    // TODO(b/238685398): Parse access and changeMode.
+
+    tryParseJsonValueToVariable(propJsonValue, "configString", /*optional=*/true,
+                                &configDecl.config.configString, errors);
+
+    tryParseJsonArrayToVariable(propJsonValue, "configArray", /*optional=*/true,
+                                &configDecl.config.configArray, errors);
+
+    parsePropValues(propJsonValue, "defaultValue", /*optional=*/true, &configDecl.initialValue,
+                    errors);
+
+    tryParseJsonValueToVariable(propJsonValue, "minSampleRate", /*optional=*/true,
+                                &configDecl.config.minSampleRate, errors);
+
+    tryParseJsonValueToVariable(propJsonValue, "maxSampleRate", /*optional=*/true,
+                                &configDecl.config.maxSampleRate, errors);
+
+    // TODO(b/238685398): AreaConfigs
+
+    if (errors->size() != initialErrorCount) {
+        return std::nullopt;
+    }
+    return configDecl;
+}
+
+Result<std::vector<ConfigDeclaration>> JsonConfigParser::parseJsonConfig(std::istream& is) {
+    Json::CharReaderBuilder builder;
+    Json::Value root;
+    std::vector<ConfigDeclaration> configs;
+    std::string errs;
+    if (!Json::parseFromStream(builder, is, &root, &errs)) {
+        return Error() << "Failed to parse property config file as JSON, error: " << errs;
+    }
+    Json::Value properties = root["properties"];
+    std::vector<std::string> errors;
+    for (unsigned int i = 0; i < properties.size(); i++) {
+        if (auto maybeConfig = parseEachProperty(properties[i], &errors); maybeConfig.has_value()) {
+            configs.push_back(std::move(maybeConfig.value()));
+        }
+    }
+    if (!errors.empty()) {
+        return Error() << android::base::Join(errors, '\n');
+    }
+    return configs;
+}
+
+}  // namespace jsonconfigloader_impl
+
+JsonConfigLoader::JsonConfigLoader() {
+    mParser = std::make_unique<jsonconfigloader_impl::JsonConfigParser>();
+}
+
+android::base::Result<std::vector<ConfigDeclaration>> JsonConfigLoader::loadPropConfig(
+        std::istream& is) {
+    return mParser->parseJsonConfig(is);
+}
+
+}  // namespace vehicle
+}  // namespace automotive
+}  // namespace hardware
+}  // namespace android
diff --git a/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/test/Android.bp b/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/test/Android.bp
new file mode 100644
index 0000000..dae37b9
--- /dev/null
+++ b/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/test/Android.bp
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+cc_test {
+    name: "JsonConfigLoaderUnitTest",
+    vendor: true,
+    srcs: ["*.cpp"],
+    static_libs: [
+        "VehicleHalJsonConfigLoader",
+        "VehicleHalUtils",
+        "libgtest",
+    ],
+    shared_libs: [
+        "libjsoncpp",
+    ],
+    defaults: ["VehicleHalDefaults"],
+    test_suites: ["device-tests"],
+}
+
+cc_test {
+    name: "JsonConfigLoaderUnitTestEnableTestProperties",
+    vendor: true,
+    srcs: ["*.cpp"],
+    static_libs: [
+        "VehicleHalJsonConfigLoaderEnableTestProperties",
+        "VehicleHalUtils",
+        "libgtest",
+    ],
+    shared_libs: [
+        "libjsoncpp",
+    ],
+    defaults: ["VehicleHalDefaults"],
+    test_suites: ["device-tests"],
+}
diff --git a/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/test/JsonConfigLoaderUnitTest.cpp b/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/test/JsonConfigLoaderUnitTest.cpp
new file mode 100644
index 0000000..469e7d6
--- /dev/null
+++ b/automotive/vehicle/aidl/impl/default_config/JsonConfigLoader/test/JsonConfigLoaderUnitTest.cpp
@@ -0,0 +1,507 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <JsonConfigLoader.h>
+
+#include <PropertyUtils.h>
+
+#include <gtest/gtest.h>
+#include <sstream>
+
+namespace android {
+namespace hardware {
+namespace automotive {
+namespace vehicle {
+
+using ::aidl::android::hardware::automotive::vehicle::RawPropValues;
+using ::aidl::android::hardware::automotive::vehicle::VehiclePropConfig;
+using ::aidl::android::hardware::automotive::vehicle::VehicleProperty;
+using ::aidl::android::hardware::automotive::vehicle::VehiclePropertyAccess;
+using ::aidl::android::hardware::automotive::vehicle::VehiclePropertyChangeMode;
+
+class JsonConfigLoaderUnitTest : public ::testing::Test {
+  protected:
+    JsonConfigLoader mLoader;
+};
+
+TEST_F(JsonConfigLoaderUnitTest, TestBasic) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": 291504388
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+
+    ASSERT_EQ(configs[0].config.prop, 291504388);
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestPropertyIsEnum) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY"
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+
+    ASSERT_EQ(configs[0].config.prop, toInt(VehicleProperty::INFO_FUEL_CAPACITY));
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestPropertyEnum_FailInvalidEnum) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::BLAH"
+        }]
+    }
+    )");
+
+    ASSERT_FALSE(mLoader.loadPropConfig(iss).ok())
+            << "Invalid VehicleProperty enum must cause error";
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestPropertyEnum_FailInvalidType) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "test"
+        }]
+    }
+    )");
+
+    ASSERT_FALSE(mLoader.loadPropConfig(iss).ok())
+            << "Invalid VehicleProperty type must cause error";
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestProperty_FailInvalidJson) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+    }
+    )");
+
+    ASSERT_FALSE(mLoader.loadPropConfig(iss);.ok()) << "Invalid JSON format must cause error";
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestConfigArray) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "configArray": [1, 2, 3]
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+    ASSERT_EQ(configs[0].config.configArray, std::vector<int>({1, 2, 3}));
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestConfigArrayConstants) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "configArray": [1, 2, "Constants::FUEL_DOOR_REAR_LEFT"]
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+    ASSERT_EQ(configs[0].config.configArray, std::vector<int>({1, 2, FUEL_DOOR_REAR_LEFT}));
+}
+
+// We have special logic to deal with GALLON and US_GALLON since they share the same value.
+TEST_F(JsonConfigLoaderUnitTest, TestConfigArrayUnitGallon) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "configArray": [1, 2, "VehicleUnit::GALLON"]
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestConfigArrayUnitUsGallon) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "configArray": [1, 2, "VehicleUnit::US_GALLON"]
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestConfigArray_FailInvalidEnum) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "configArray": [1, 2, "VehicleUnits::BLAH"]
+        }]
+    }
+    )");
+
+    ASSERT_FALSE(mLoader.loadPropConfig(iss).ok())
+            << "Invalid enum in ConfigArray must cause error";
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestConfigArray_FailNotArray) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "configArray": "123"
+        }]
+    }
+    )");
+
+    ASSERT_FALSE(mLoader.loadPropConfig(iss).ok())
+            << "ConfigArray is not an array must cause error";
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestConfigString) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "configString": "test"
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+    ASSERT_EQ(configs[0].config.configString, "test");
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestConfigString_FailNotString) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "configString": 1234
+        }]
+    }
+    )");
+
+    ASSERT_FALSE(mLoader.loadPropConfig(iss).ok())
+            << "ConfigString is not a String must cause error";
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestCheckDefaultAccessChangeMode) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY"
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+
+    const VehiclePropConfig& propConfig = configs[0].config;
+    ASSERT_EQ(propConfig.access, VehiclePropertyAccess::READ);
+    ASSERT_EQ(propConfig.changeMode, VehiclePropertyChangeMode::STATIC);
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestAccessOverride) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "access": "VehiclePropertyAccess::WRITE"
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+
+    const VehiclePropConfig& propConfig = configs[0].config;
+    ASSERT_EQ(propConfig.access, VehiclePropertyAccess::WRITE);
+    ASSERT_EQ(propConfig.changeMode, VehiclePropertyChangeMode::STATIC);
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestChangeModeOverride) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "changeMode": "VehiclePropertyChangeMode::ON_CHANGE"
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+
+    const VehiclePropConfig& propConfig = configs[0].config;
+    ASSERT_EQ(propConfig.access, VehiclePropertyAccess::READ);
+    ASSERT_EQ(propConfig.changeMode, VehiclePropertyChangeMode::ON_CHANGE);
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestCustomProp) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": 1234,
+            "access": "VehiclePropertyAccess::WRITE",
+            "changeMode": "VehiclePropertyChangeMode::ON_CHANGE"
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+
+    const VehiclePropConfig& propConfig = configs[0].config;
+    ASSERT_EQ(propConfig.access, VehiclePropertyAccess::WRITE);
+    ASSERT_EQ(propConfig.changeMode, VehiclePropertyChangeMode::ON_CHANGE);
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestCustomProp_FailMissingAccess) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": 1234,
+            "changeMode": "VehiclePropertyChangeMode::ON_CHANGE"
+        }]
+    }
+    )");
+
+    ASSERT_FALSE(mLoader.loadPropConfig(iss).ok())
+            << "Missing access for custom property must cause error";
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestCustomProp_FailMissingChangeMode) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": 1234,
+            "access": "VehiclePropertyAccess::WRITE"
+        }]
+    }
+    )");
+
+    ASSERT_FALSE(mLoader.loadPropConfig(iss).ok())
+            << "Missing change mode for custom property must cause error";
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestMinSampleRate) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "minSampleRate": 1,
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+    ASSERT_EQ(configs[0].config.minSampleRate, 1);
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestMinSampleRate_FailInvalidType) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "minSampleRate": "abcd",
+        }]
+    }
+    )");
+
+    ASSERT_FALSE(mLoader.loadPropConfig(iss).ok())
+            << "Wrong type for MinSampleRate must cause error";
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestMaxSampleRate) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "maxSampleRate": 1,
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+    ASSERT_EQ(configs[0].config.maxSampleRate, 1);
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestMaxSampleRate_FailInvalidType) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "maxSampleRate": "abcd",
+        }]
+    }
+    )");
+
+    ASSERT_FALSE(mLoader.loadPropConfig(iss).ok())
+            << "Wrong type for MaxSampleRate must cause error";
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestDefaultValue_Simple) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "defaultValue": {
+                "int32Values": [1, 2]
+            }
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+    ASSERT_EQ(configs[0].initialValue.int32Values, std::vector<int32_t>({1, 2}));
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestDefaultValue_Mixed) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "defaultValue": {
+                "int32Values": [1, "Constants::FUEL_DOOR_REAR_LEFT"],
+                "int64Values": [2, "Constants::FUEL_DOOR_REAR_LEFT"],
+                "floatValues": [3.0, "Constants::FUEL_DOOR_REAR_LEFT"],
+                "stringValue": "abcd"
+            }
+        }]
+    }
+    )");
+
+    auto result = mLoader.loadPropConfig(iss);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+
+    auto configs = result.value();
+    ASSERT_EQ(configs.size(), 1u);
+
+    const RawPropValues& initialValue = configs[0].initialValue;
+    ASSERT_EQ(initialValue.int32Values, std::vector<int32_t>({1, FUEL_DOOR_REAR_LEFT}));
+    ASSERT_EQ(initialValue.int64Values,
+              std::vector<int64_t>({2, static_cast<int64_t>(FUEL_DOOR_REAR_LEFT)}));
+    ASSERT_EQ(initialValue.floatValues,
+              std::vector<float>({3.0, static_cast<float>(FUEL_DOOR_REAR_LEFT)}));
+    ASSERT_EQ(initialValue.stringValue, "abcd");
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestDefaultValue_FailNotObject) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "defaultValue": []
+        }]
+    }
+    )");
+
+    ASSERT_FALSE(mLoader.loadPropConfig(iss).ok())
+            << "DefaultValue is not an object must cause error";
+}
+
+TEST_F(JsonConfigLoaderUnitTest, TestDefaultValue_FailInvalidType) {
+    std::istringstream iss(R"(
+    {
+        "properties": [{
+            "property": "VehicleProperty::INFO_FUEL_CAPACITY",
+            "defaultValue": [{
+                "int32Values": [1.1]
+            }]
+        }]
+    }
+    )");
+
+    ASSERT_FALSE(mLoader.loadPropConfig(iss).ok())
+            << "Wrong type for DefaultValue must cause error";
+}
+
+}  // namespace vehicle
+}  // namespace automotive
+}  // namespace hardware
+}  // namespace android
diff --git a/automotive/vehicle/aidl/impl/default_config/include/DefaultConfig.h b/automotive/vehicle/aidl/impl/default_config/include/DefaultConfig.h
index 1ff3f33..b1ed0c0 100644
--- a/automotive/vehicle/aidl/impl/default_config/include/DefaultConfig.h
+++ b/automotive/vehicle/aidl/impl/default_config/include/DefaultConfig.h
@@ -17,6 +17,7 @@
 #ifndef android_hardware_automotive_vehicle_aidl_impl_default_config_include_DefaultConfig_H_
 #define android_hardware_automotive_vehicle_aidl_impl_default_config_include_DefaultConfig_H_
 
+#include <ConfigDeclaration.h>
 #include <PropertyUtils.h>
 #include <TestPropertyUtils.h>
 #include <VehicleHalTypes.h>
@@ -56,17 +57,6 @@
 using ::aidl::android::hardware::automotive::vehicle::VehicleUnit;
 using ::aidl::android::hardware::automotive::vehicle::VehicleVendorPermission;
 
-struct ConfigDeclaration {
-    VehiclePropConfig config;
-
-    // This value will be used as an initial value for the property. If this field is specified for
-    // property that supports multiple areas then it will be used for all areas unless particular
-    // area is overridden in initialAreaValue field.
-    RawPropValues initialValue;
-    // Use initialAreaValues if it is necessary to specify different values per each area.
-    std::map<int32_t, RawPropValues> initialAreaValues;
-};
-
 const std::vector<ConfigDeclaration> kVehicleProperties = {
         {.config =
                  {
@@ -1549,8 +1539,6 @@
 // public namespace
 namespace defaultconfig {
 
-typedef defaultconfig_impl::ConfigDeclaration ConfigDeclaration;
-
 inline constexpr const std::vector<ConfigDeclaration>& getDefaultConfigs() {
     return defaultconfig_impl::kVehicleProperties;
 }
diff --git a/automotive/vehicle/aidl/impl/default_config/test/Android.bp b/automotive/vehicle/aidl/impl/default_config/test/Android.bp
index 771472c..b05d47c 100644
--- a/automotive/vehicle/aidl/impl/default_config/test/Android.bp
+++ b/automotive/vehicle/aidl/impl/default_config/test/Android.bp
@@ -24,11 +24,53 @@
     defaults: ["VehicleHalDefaults"],
     srcs: ["*.cpp"],
     static_libs: [
+        "VehicleHalJsonConfigLoader",
         "VehicleHalUtils",
+        "libgmock",
         "libgtest",
     ],
     header_libs: [
+        // TODO(b/238685398): Remove this once we deprecate DefaultConfig.h
         "VehicleHalDefaultConfig",
+        "IVehicleGeneratedHeaders",
+    ],
+    shared_libs: [
+        "libjsoncpp",
+    ],
+    data: [
+        ":VehicleHalDefaultProperties_JSON",
+    ],
+    test_suites: ["device-tests"],
+}
+
+cc_test {
+    name: "VehicleHalDefaultConfigTestEnableTestProperties",
+    vendor: true,
+    defaults: ["VehicleHalDefaults"],
+    srcs: ["*.cpp"],
+    static_libs: [
+        "VehicleHalJsonConfigLoaderEnableTestProperties",
+        "VehicleHalUtils",
+        "libgmock",
+        "libgtest",
+    ],
+    cflags: [
+        // TODO(b/238685398): Remove this once we deprecate DefaultConfig.h
+        "-DENABLE_VENDOR_CLUSTER_PROPERTY_FOR_TESTING",
+        "-DENABLE_VEHICLE_HAL_TEST_PROPERTIES",
+    ],
+    header_libs: [
+        // TODO(b/238685398): Remove this once we deprecate DefaultConfig.h
+        "VehicleHalDefaultConfig",
+        "IVehicleGeneratedHeaders",
+    ],
+    shared_libs: [
+        "libjsoncpp",
+    ],
+    data: [
+        ":VehicleHalDefaultProperties_JSON",
+        ":VehicleHalTestProperties_JSON",
+        ":VehicleHalVendorClusterTestProperties_JSON",
     ],
     test_suites: ["device-tests"],
 }
diff --git a/automotive/vehicle/aidl/impl/default_config/test/DefaultConfigTest.cpp b/automotive/vehicle/aidl/impl/default_config/test/DefaultConfigTest.cpp
index baaae75..ba1100f 100644
--- a/automotive/vehicle/aidl/impl/default_config/test/DefaultConfigTest.cpp
+++ b/automotive/vehicle/aidl/impl/default_config/test/DefaultConfigTest.cpp
@@ -15,26 +15,92 @@
  */
 
 #include <DefaultConfig.h>
+#include <JsonConfigLoader.h>
 #include <VehicleUtils.h>
+#include <android-base/file.h>
+#include <gmock/gmock.h>
 #include <gtest/gtest.h>
+#include <fstream>
 
 namespace android {
 namespace hardware {
 namespace automotive {
 namespace vehicle {
-namespace defaultconfig {
 
 namespace test {
 
-TEST(DefaultConfigTest, loadDefaultConfigs) {
-    for (ConfigDeclaration config : getDefaultConfigs()) {
-        ASSERT_NE(0, config.config.prop);
-    }
+using ::android::base::Error;
+using ::android::base::Result;
+using ::testing::UnorderedElementsAreArray;
+
+constexpr char kDefaultPropertiesConfigFile[] = "DefaultProperties.json";
+
+#ifdef ENABLE_VEHICLE_HAL_TEST_PROPERTIES
+constexpr char kTestPropertiesConfigFile[] = "TestProperties.json";
+constexpr char kVendorClusterTestPropertiesConfigFile[] = "VendorClusterTestProperties.json";
+#endif  // ENABLE_VEHICLE_HAL_TEST_PROPERTIES
+
+std::string getTestFilePath(const char* filename) {
+    static std::string baseDir = android::base::GetExecutableDirectory();
+    return baseDir + "/" + filename;
 }
 
+Result<std::vector<ConfigDeclaration>> loadConfig(JsonConfigLoader& loader, const char* path) {
+    std::string configPath = getTestFilePath(path);
+    std::ifstream ifs(configPath.c_str());
+    if (!ifs) {
+        return Error() << "couldn't open %s for parsing." << configPath;
+    }
+
+    return loader.loadPropConfig(ifs);
+}
+
+TEST(DefaultConfigTest, TestloadDefaultProperties) {
+    JsonConfigLoader loader;
+    auto result = loadConfig(loader, kDefaultPropertiesConfigFile);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+}
+
+#ifdef ENABLE_VEHICLE_HAL_TEST_PROPERTIES
+
+TEST(DefaultConfigTest, TestloadTestProperties) {
+    JsonConfigLoader loader;
+    auto result = loadConfig(loader, kTestPropertiesConfigFile);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+}
+
+TEST(DefaultConfigTest, TestloadVendorClusterTestProperties) {
+    JsonConfigLoader loader;
+    auto result = loadConfig(loader, kVendorClusterTestPropertiesConfigFile);
+
+    ASSERT_TRUE(result.ok()) << result.error().message();
+}
+
+// TODO(b/238685398): Remove this test after we deprecate DefaultConfig.h
+TEST(DefaultConfigTest, TestCompatibleWithDefaultConfigHeader) {
+    auto configsFromHeaderFile = defaultconfig::getDefaultConfigs();
+
+    std::vector<ConfigDeclaration> configsFromJson;
+    JsonConfigLoader loader;
+    for (const char* file :
+         std::vector<const char*>({kDefaultPropertiesConfigFile, kTestPropertiesConfigFile,
+                                   kVendorClusterTestPropertiesConfigFile})) {
+        auto result = loadConfig(loader, file);
+        ASSERT_TRUE(result.ok()) << result.error().message();
+        configsFromJson.insert(configsFromJson.end(), result.value().begin(), result.value().end());
+    }
+
+    ASSERT_EQ(configsFromHeaderFile.size(), configsFromJson.size());
+    // TODO(b/238685398): Uncomment this once we finish the parser.
+    // ASSERT_THAT(configsFromHeaderFile, UnorderedElementsAreArray(configsFromJson));
+}
+
+#endif  // ENABLE_VEHICLE_HAL_TEST_PROPERTIES
+
 }  // namespace test
 
-}  // namespace defaultconfig
 }  // namespace vehicle
 }  // namespace automotive
 }  // namespace hardware
diff --git a/automotive/vehicle/aidl/impl/fake_impl/hardware/include/FakeVehicleHardware.h b/automotive/vehicle/aidl/impl/fake_impl/hardware/include/FakeVehicleHardware.h
index 8cc19b1..9091fee 100644
--- a/automotive/vehicle/aidl/impl/fake_impl/hardware/include/FakeVehicleHardware.h
+++ b/automotive/vehicle/aidl/impl/fake_impl/hardware/include/FakeVehicleHardware.h
@@ -153,7 +153,7 @@
 
     void init();
     // Stores the initial value to property store.
-    void storePropInitialValue(const defaultconfig::ConfigDeclaration& config);
+    void storePropInitialValue(const ConfigDeclaration& config);
     // The callback that would be called when a vehicle property value change happens.
     void onValueChangeCallback(
             const aidl::android::hardware::automotive::vehicle::VehiclePropValue& value);
diff --git a/automotive/vehicle/aidl/impl/fake_impl/hardware/src/FakeVehicleHardware.cpp b/automotive/vehicle/aidl/impl/fake_impl/hardware/src/FakeVehicleHardware.cpp
index 7c451fe..c6ec85d 100644
--- a/automotive/vehicle/aidl/impl/fake_impl/hardware/src/FakeVehicleHardware.cpp
+++ b/automotive/vehicle/aidl/impl/fake_impl/hardware/src/FakeVehicleHardware.cpp
@@ -97,7 +97,7 @@
 
 }  // namespace
 
-void FakeVehicleHardware::storePropInitialValue(const defaultconfig::ConfigDeclaration& config) {
+void FakeVehicleHardware::storePropInitialValue(const ConfigDeclaration& config) {
     const VehiclePropConfig& vehiclePropConfig = config.config;
     int propId = vehiclePropConfig.prop;
 
diff --git a/automotive/vehicle/aidl/impl/utils/test/include/TestPropertyUtils.h b/automotive/vehicle/aidl/impl/utils/test/include/TestPropertyUtils.h
index d512713..e6ea6fe 100644
--- a/automotive/vehicle/aidl/impl/utils/test/include/TestPropertyUtils.h
+++ b/automotive/vehicle/aidl/impl/utils/test/include/TestPropertyUtils.h
@@ -35,7 +35,6 @@
 
 }  // namespace testpropertyutils_impl
 
-#ifdef ENABLE_VENDOR_CLUSTER_PROPERTY_FOR_TESTING
 // Converts the system property to the vendor property.
 // WARNING: This is only for the end-to-end testing, Should NOT include in the user build.
 inline constexpr int32_t toVendor(
@@ -55,7 +54,6 @@
         toVendor(testpropertyutils_impl::VehicleProperty::CLUSTER_REQUEST_DISPLAY);
 constexpr int32_t VENDOR_CLUSTER_NAVIGATION_STATE =
         toVendor(testpropertyutils_impl::VehicleProperty::CLUSTER_NAVIGATION_STATE);
-#endif  // ENABLE_VENDOR_CLUSTER_PROPERTY_FOR_TESTING
 
 // These properties are placeholder properties for developers to test new features without
 // implementing a real property.