common/device/com/android/net/module/util/DeviceConfigUtils.java - platform/frameworks/libs/net - Git at Google

 /*
  * Copyright (C) 2020 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 com.android.net.module.util;

 import android.content.Context;
 import android.content.pm.ModuleInfo;
 import android.content.pm.PackageManager;
 import android.content.res.Resources;
 import android.provider.DeviceConfig;
 import android.util.Log;

 import androidx.annotation.BoolRes;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.annotation.VisibleForTesting;

 /**
  * Utilities for modules to query {@link DeviceConfig} and flags.
  */
 public final class DeviceConfigUtils {
     private DeviceConfigUtils() {}

     private static final String TAG = DeviceConfigUtils.class.getSimpleName();
     /**
      * DO NOT MODIFY: this may be used by multiple modules that will not see the updated value
      * until they are recompiled, so modifying this constant means that different modules may
      * be referencing a different tethering module variant, or having a stale reference.
      */
     public static final String TETHERING_MODULE_NAME = "com.android.tethering";

     @VisibleForTesting
     public static void resetPackageVersionCacheForTest() {
         sPackageVersion = -1;
         sModuleVersion = -1;
     }

     private static volatile long sPackageVersion = -1;
     private static long getPackageVersion(@NonNull final Context context)
             throws PackageManager.NameNotFoundException {
         // sPackageVersion may be set by another thread just after this check, but querying the
         // package version several times on rare occasions is fine.
         if (sPackageVersion >= 0) {
             return sPackageVersion;
         }
         final long version = context.getPackageManager().getPackageInfo(
                 context.getPackageName(), 0).getLongVersionCode();
         sPackageVersion = version;
         return version;
     }

     /**
      * Look up the value of a property for a particular namespace from {@link DeviceConfig}.
      * @param namespace The namespace containing the property to look up.
      * @param name The name of the property to look up.
      * @param defaultValue The value to return if the property does not exist or has no valid value.
      * @return the corresponding value, or defaultValue if none exists.
      */
     @Nullable
     public static String getDeviceConfigProperty(@NonNull String namespace, @NonNull String name,
             @Nullable String defaultValue) {
         String value = DeviceConfig.getProperty(namespace, name);
         return value != null ? value : defaultValue;
     }

     /**
      * Look up the value of a property for a particular namespace from {@link DeviceConfig}.
      * @param namespace The namespace containing the property to look up.
      * @param name The name of the property to look up.
      * @param defaultValue The value to return if the property does not exist or its value is null.
      * @return the corresponding value, or defaultValue if none exists.
      */
     public static int getDeviceConfigPropertyInt(@NonNull String namespace, @NonNull String name,
             int defaultValue) {
         String value = getDeviceConfigProperty(namespace, name, null /* defaultValue */);
         try {
             return (value != null) ? Integer.parseInt(value) : defaultValue;
         } catch (NumberFormatException e) {
             return defaultValue;
         }
     }

     /**
      * Look up the value of a property for a particular namespace from {@link DeviceConfig}.
      *
      * Flags like timeouts should use this method and set an appropriate min/max range: if invalid
      * values like "0" or "1" are pushed to devices, everything would timeout. The min/max range
      * protects against this kind of breakage.
      * @param namespace The namespace containing the property to look up.
      * @param name The name of the property to look up.
      * @param minimumValue The minimum value of a property.
      * @param maximumValue The maximum value of a property.
      * @param defaultValue The value to return if the property does not exist or its value is null.
      * @return the corresponding value, or defaultValue if none exists or the fetched value is
      *         not in the provided range.
      */
     public static int getDeviceConfigPropertyInt(@NonNull String namespace, @NonNull String name,
             int minimumValue, int maximumValue, int defaultValue) {
         int value = getDeviceConfigPropertyInt(namespace, name, defaultValue);
         if (value < minimumValue || value > maximumValue) return defaultValue;
         return value;
     }

     /**
      * Look up the value of a property for a particular namespace from {@link DeviceConfig}.
      * @param namespace The namespace containing the property to look up.
      * @param name The name of the property to look up.
      * @param defaultValue The value to return if the property does not exist or its value is null.
      * @return the corresponding value, or defaultValue if none exists.
      */
     public static boolean getDeviceConfigPropertyBoolean(@NonNull String namespace,
             @NonNull String name, boolean defaultValue) {
         String value = getDeviceConfigProperty(namespace, name, null /* defaultValue */);
         return (value != null) ? Boolean.parseBoolean(value) : defaultValue;
     }

     /**
      * Check whether or not one specific experimental feature for a particular namespace from
      * {@link DeviceConfig} is enabled by comparing module package version
      * with current version of property. If this property version is valid, the corresponding
      * experimental feature would be enabled, otherwise disabled.
      *
      * This is useful to ensure that if a module install is rolled back, flags are not left fully
      * rolled out on a version where they have not been well tested.
      * @param context The global context information about an app environment.
      * @param namespace The namespace containing the property to look up.
      * @param name The name of the property to look up.
      * @return true if this feature is enabled, or false if disabled.
      */
     public static boolean isFeatureEnabled(@NonNull Context context, @NonNull String namespace,
             @NonNull String name) {
         return isFeatureEnabled(context, namespace, name, false /* defaultEnabled */);
     }

     /**
      * Check whether or not one specific experimental feature for a particular namespace from
      * {@link DeviceConfig} is enabled by comparing module package version
      * with current version of property. If this property version is valid, the corresponding
      * experimental feature would be enabled, otherwise disabled.
      *
      * This is useful to ensure that if a module install is rolled back, flags are not left fully
      * rolled out on a version where they have not been well tested.
      * @param context The global context information about an app environment.
      * @param namespace The namespace containing the property to look up.
      * @param name The name of the property to look up.
      * @param defaultEnabled The value to return if the property does not exist or its value is
      *                       null.
      * @return true if this feature is enabled, or false if disabled.
      */
     public static boolean isFeatureEnabled(@NonNull Context context, @NonNull String namespace,
             @NonNull String name, boolean defaultEnabled) {
         try {
             final long packageVersion = getPackageVersion(context);
             return isFeatureEnabled(context, packageVersion, namespace, name, defaultEnabled);
         } catch (PackageManager.NameNotFoundException e) {
             Log.e(TAG, "Could not find the package name", e);
             return false;
         }
     }

     /**
      * Check whether or not one specific experimental feature for a particular namespace from
      * {@link DeviceConfig} is enabled by comparing module package version
      * with current version of property. If this property version is valid, the corresponding
      * experimental feature would be enabled, otherwise disabled.
      *
      * This is useful to ensure that if a module install is rolled back, flags are not left fully
      * rolled out on a version where they have not been well tested.
      * @param context The global context information about an app environment.
      * @param namespace The namespace containing the property to look up.
      * @param name The name of the property to look up.
      * @param moduleName The mainline module name which is released as apex.
      * @param defaultEnabled The value to return if the property does not exist or its value is
      *                       null.
      * @return true if this feature is enabled, or false if disabled.
      */
     public static boolean isFeatureEnabled(@NonNull Context context, @NonNull String namespace,
             @NonNull String name, @NonNull String moduleName, boolean defaultEnabled) {
         try {
             final long packageVersion = getModuleVersion(context, moduleName);
             return isFeatureEnabled(context, packageVersion, namespace, name, defaultEnabled);
         } catch (PackageManager.NameNotFoundException e) {
             Log.e(TAG, "Could not find the module name", e);
             return false;
         }
     }

     private static boolean maybeUseFixedPackageVersion(@NonNull Context context) {
         final String packageName = context.getPackageName();
         if (packageName == null) return false;

         return packageName.equals("com.android.networkstack.tethering")
                 || packageName.equals("com.android.networkstack.tethering.inprocess");
     }

     private static boolean isFeatureEnabled(@NonNull Context context, long packageVersion,
             @NonNull String namespace, String name, boolean defaultEnabled)
             throws PackageManager.NameNotFoundException {
         final int propertyVersion = getDeviceConfigPropertyInt(namespace, name,
                 0 /* default value */);
         return (propertyVersion == 0 && defaultEnabled)
                 || (propertyVersion != 0 && packageVersion >= (long) propertyVersion);
     }

     private static volatile long sModuleVersion = -1;
     @VisibleForTesting public static long FIXED_PACKAGE_VERSION = 10;
     private static long getModuleVersion(@NonNull Context context, @NonNull String moduleName)
             throws PackageManager.NameNotFoundException {
         if (sModuleVersion >= 0) return sModuleVersion;

         final PackageManager packageManager = context.getPackageManager();
         ModuleInfo module;
         try {
             module = packageManager.getModuleInfo(
                     moduleName, PackageManager.MODULE_APEX_NAME);
         } catch (PackageManager.NameNotFoundException e) {
             // The error may happen if mainline module meta data is not installed e.g. there are
             // no meta data configuration in AOSP build. To be able to enable a feature in AOSP
             // by setting a flag via ADB for example. set a small non-zero fixed number for
             // comparing.
             if (maybeUseFixedPackageVersion(context)) {
                 sModuleVersion = FIXED_PACKAGE_VERSION;
                 return FIXED_PACKAGE_VERSION;
             } else {
                 throw e;
             }
         }
         String modulePackageName = module.getPackageName();
         if (modulePackageName == null) throw new PackageManager.NameNotFoundException(moduleName);
         final long version = packageManager.getPackageInfo(modulePackageName,
                 PackageManager.MATCH_APEX).getLongVersionCode();
         sModuleVersion = version;

         return version;
     }

     /**
      * Gets boolean config from resources.
      */
     public static boolean getResBooleanConfig(@NonNull final Context context,
             @BoolRes int configResource, final boolean defaultValue) {
         final Resources res = context.getResources();
         try {
             return res.getBoolean(configResource);
         } catch (Resources.NotFoundException e) {
             return defaultValue;
         }
     }
 }
	/*
	* Copyright (C) 2020 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 com.android.net.module.util;

	import android.content.Context;
	import android.content.pm.ModuleInfo;
	import android.content.pm.PackageManager;
	import android.content.res.Resources;
	import android.provider.DeviceConfig;
	import android.util.Log;

	import androidx.annotation.BoolRes;
	import androidx.annotation.NonNull;
	import androidx.annotation.Nullable;
	import androidx.annotation.VisibleForTesting;

	/**
	* Utilities for modules to query {@link DeviceConfig} and flags.
	*/
	public final class DeviceConfigUtils {
	private DeviceConfigUtils() {}

	private static final String TAG = DeviceConfigUtils.class.getSimpleName();
	/**
	* DO NOT MODIFY: this may be used by multiple modules that will not see the updated value
	* until they are recompiled, so modifying this constant means that different modules may
	* be referencing a different tethering module variant, or having a stale reference.
	*/
	public static final String TETHERING_MODULE_NAME = "com.android.tethering";

	@VisibleForTesting
	public static void resetPackageVersionCacheForTest() {
	sPackageVersion = -1;
	sModuleVersion = -1;
	}

	private static volatile long sPackageVersion = -1;
	private static long getPackageVersion(@NonNull final Context context)
	throws PackageManager.NameNotFoundException {
	// sPackageVersion may be set by another thread just after this check, but querying the
	// package version several times on rare occasions is fine.
	if (sPackageVersion >= 0) {
	return sPackageVersion;
	}
	final long version = context.getPackageManager().getPackageInfo(
	context.getPackageName(), 0).getLongVersionCode();
	sPackageVersion = version;
	return version;
	}

	/**
	* Look up the value of a property for a particular namespace from {@link DeviceConfig}.
	* @param namespace The namespace containing the property to look up.
	* @param name The name of the property to look up.
	* @param defaultValue The value to return if the property does not exist or has no valid value.
	* @return the corresponding value, or defaultValue if none exists.
	*/
	@Nullable
	public static String getDeviceConfigProperty(@NonNull String namespace, @NonNull String name,
	@Nullable String defaultValue) {
	String value = DeviceConfig.getProperty(namespace, name);
	return value != null ? value : defaultValue;
	}

	/**
	* Look up the value of a property for a particular namespace from {@link DeviceConfig}.
	* @param namespace The namespace containing the property to look up.
	* @param name The name of the property to look up.
	* @param defaultValue The value to return if the property does not exist or its value is null.
	* @return the corresponding value, or defaultValue if none exists.
	*/
	public static int getDeviceConfigPropertyInt(@NonNull String namespace, @NonNull String name,
	int defaultValue) {
	String value = getDeviceConfigProperty(namespace, name, null /* defaultValue */);
	try {
	return (value != null) ? Integer.parseInt(value) : defaultValue;
	} catch (NumberFormatException e) {
	return defaultValue;
	}
	}

	/**
	* Look up the value of a property for a particular namespace from {@link DeviceConfig}.
	*
	* Flags like timeouts should use this method and set an appropriate min/max range: if invalid
	* values like "0" or "1" are pushed to devices, everything would timeout. The min/max range
	* protects against this kind of breakage.
	* @param namespace The namespace containing the property to look up.
	* @param name The name of the property to look up.
	* @param minimumValue The minimum value of a property.
	* @param maximumValue The maximum value of a property.
	* @param defaultValue The value to return if the property does not exist or its value is null.
	* @return the corresponding value, or defaultValue if none exists or the fetched value is
	* not in the provided range.
	*/
	public static int getDeviceConfigPropertyInt(@NonNull String namespace, @NonNull String name,
	int minimumValue, int maximumValue, int defaultValue) {
	int value = getDeviceConfigPropertyInt(namespace, name, defaultValue);
	if (value < minimumValue \|\| value > maximumValue) return defaultValue;
	return value;
	}

	/**
	* Look up the value of a property for a particular namespace from {@link DeviceConfig}.
	* @param namespace The namespace containing the property to look up.
	* @param name The name of the property to look up.
	* @param defaultValue The value to return if the property does not exist or its value is null.
	* @return the corresponding value, or defaultValue if none exists.
	*/
	public static boolean getDeviceConfigPropertyBoolean(@NonNull String namespace,
	@NonNull String name, boolean defaultValue) {
	String value = getDeviceConfigProperty(namespace, name, null /* defaultValue */);
	return (value != null) ? Boolean.parseBoolean(value) : defaultValue;
	}

	/**
	* Check whether or not one specific experimental feature for a particular namespace from
	* {@link DeviceConfig} is enabled by comparing module package version
	* with current version of property. If this property version is valid, the corresponding
	* experimental feature would be enabled, otherwise disabled.
	*
	* This is useful to ensure that if a module install is rolled back, flags are not left fully
	* rolled out on a version where they have not been well tested.
	* @param context The global context information about an app environment.
	* @param namespace The namespace containing the property to look up.
	* @param name The name of the property to look up.
	* @return true if this feature is enabled, or false if disabled.
	*/
	public static boolean isFeatureEnabled(@NonNull Context context, @NonNull String namespace,
	@NonNull String name) {
	return isFeatureEnabled(context, namespace, name, false /* defaultEnabled */);
	}

	/**
	* Check whether or not one specific experimental feature for a particular namespace from
	* {@link DeviceConfig} is enabled by comparing module package version
	* with current version of property. If this property version is valid, the corresponding
	* experimental feature would be enabled, otherwise disabled.
	*
	* This is useful to ensure that if a module install is rolled back, flags are not left fully
	* rolled out on a version where they have not been well tested.
	* @param context The global context information about an app environment.
	* @param namespace The namespace containing the property to look up.
	* @param name The name of the property to look up.
	* @param defaultEnabled The value to return if the property does not exist or its value is
	* null.
	* @return true if this feature is enabled, or false if disabled.
	*/
	public static boolean isFeatureEnabled(@NonNull Context context, @NonNull String namespace,
	@NonNull String name, boolean defaultEnabled) {
	try {
	final long packageVersion = getPackageVersion(context);
	return isFeatureEnabled(context, packageVersion, namespace, name, defaultEnabled);
	} catch (PackageManager.NameNotFoundException e) {
	Log.e(TAG, "Could not find the package name", e);
	return false;
	}
	}

	/**
	* Check whether or not one specific experimental feature for a particular namespace from
	* {@link DeviceConfig} is enabled by comparing module package version
	* with current version of property. If this property version is valid, the corresponding
	* experimental feature would be enabled, otherwise disabled.
	*
	* This is useful to ensure that if a module install is rolled back, flags are not left fully
	* rolled out on a version where they have not been well tested.
	* @param context The global context information about an app environment.
	* @param namespace The namespace containing the property to look up.
	* @param name The name of the property to look up.
	* @param moduleName The mainline module name which is released as apex.
	* @param defaultEnabled The value to return if the property does not exist or its value is
	* null.
	* @return true if this feature is enabled, or false if disabled.
	*/
	public static boolean isFeatureEnabled(@NonNull Context context, @NonNull String namespace,
	@NonNull String name, @NonNull String moduleName, boolean defaultEnabled) {
	try {
	final long packageVersion = getModuleVersion(context, moduleName);
	return isFeatureEnabled(context, packageVersion, namespace, name, defaultEnabled);
	} catch (PackageManager.NameNotFoundException e) {
	Log.e(TAG, "Could not find the module name", e);
	return false;
	}
	}

	private static boolean maybeUseFixedPackageVersion(@NonNull Context context) {
	final String packageName = context.getPackageName();
	if (packageName == null) return false;

	return packageName.equals("com.android.networkstack.tethering")
	\|\| packageName.equals("com.android.networkstack.tethering.inprocess");
	}

	private static boolean isFeatureEnabled(@NonNull Context context, long packageVersion,
	@NonNull String namespace, String name, boolean defaultEnabled)
	throws PackageManager.NameNotFoundException {
	final int propertyVersion = getDeviceConfigPropertyInt(namespace, name,
	0 /* default value */);
	return (propertyVersion == 0 && defaultEnabled)
	\|\| (propertyVersion != 0 && packageVersion >= (long) propertyVersion);
	}

	private static volatile long sModuleVersion = -1;
	@VisibleForTesting public static long FIXED_PACKAGE_VERSION = 10;
	private static long getModuleVersion(@NonNull Context context, @NonNull String moduleName)
	throws PackageManager.NameNotFoundException {
	if (sModuleVersion >= 0) return sModuleVersion;

	final PackageManager packageManager = context.getPackageManager();
	ModuleInfo module;
	try {
	module = packageManager.getModuleInfo(
	moduleName, PackageManager.MODULE_APEX_NAME);
	} catch (PackageManager.NameNotFoundException e) {
	// The error may happen if mainline module meta data is not installed e.g. there are
	// no meta data configuration in AOSP build. To be able to enable a feature in AOSP
	// by setting a flag via ADB for example. set a small non-zero fixed number for
	// comparing.
	if (maybeUseFixedPackageVersion(context)) {
	sModuleVersion = FIXED_PACKAGE_VERSION;
	return FIXED_PACKAGE_VERSION;
	} else {
	throw e;
	}
	}
	String modulePackageName = module.getPackageName();
	if (modulePackageName == null) throw new PackageManager.NameNotFoundException(moduleName);
	final long version = packageManager.getPackageInfo(modulePackageName,
	PackageManager.MATCH_APEX).getLongVersionCode();
	sModuleVersion = version;

	return version;
	}

	/**
	* Gets boolean config from resources.
	*/
	public static boolean getResBooleanConfig(@NonNull final Context context,
	@BoolRes int configResource, final boolean defaultValue) {
	final Resources res = context.getResources();
	try {
	return res.getBoolean(configResource);
	} catch (Resources.NotFoundException e) {
	return defaultValue;
	}
	}
	}