Allow jcache to load its configuration from a uri (fixes #877)

config/spotbugs/exclude.xml

@@ -334,6 +334,21 @@
     <Method name="deserialize"/>
     <Bug pattern="OBJECT_DESERIALIZATION"/>
   </Match>
+  <Match>
+    <Class name="com.github.benmanes.caffeine.jcache.configuration.TypesafeConfigurator"/>
+    <Method name="resolveConfig"/>
+    <Bug pattern="PATH_TRAVERSAL_IN"/>
+  </Match>
+  <Match>
+    <Class name="com.github.benmanes.caffeine.jcache.configuration.TypesafeConfigurator"/>
+    <Method name="resolveConfig"/>
+    <Bug pattern="IMPROPER_UNICODE"/>
+  </Match>
+  <Match>
+    <Class name="com.github.benmanes.caffeine.jcache.configuration.TypesafeConfigurator"/>
+    <Method name="isResource"/>
+    <Bug pattern="IMPROPER_UNICODE"/>
+  </Match>
   <Match>
     <Class name="com.github.benmanes.caffeine.jcache.configuration.TypesafeConfigurator$Configurator"/>
     <Method name="addLazyExpiration"/>

jcache/src/main/java/com/github/benmanes/caffeine/jcache/CacheFactory.java

@@ -56,23 +56,24 @@ private CacheFactory() {}
   /**
    * Returns if the cache definition is found in the external settings file.
    *
+   * @param cacheManager the owner
    * @param cacheName the name of the cache
    * @return {@code true} if a definition exists
    */
-  public static boolean isDefinedExternally(String cacheName) {
-    return TypesafeConfigurator.cacheNames(rootConfig()).contains(cacheName);
+  public static boolean isDefinedExternally(CacheManager cacheManager, String cacheName) {
+    return TypesafeConfigurator.cacheNames(rootConfig(cacheManager)).contains(cacheName);
   }
 
   /**
    * Returns a newly created cache instance if a definition is found in the external settings file.
    *
-   * @param cacheManager the owner of the cache instance
+   * @param cacheManager the owner
    * @param cacheName the name of the cache
    * @return a new cache instance or null if the named cache is not defined in the settings file
    */
   public static @Nullable <K, V> CacheProxy<K, V> tryToCreateFromExternalSettings(
       CacheManager cacheManager, String cacheName) {
-    return TypesafeConfigurator.<K, V>from(rootConfig(), cacheName)
+    return TypesafeConfigurator.<K, V>from(rootConfig(cacheManager), cacheName)
         .map(configuration -> createCache(cacheManager, cacheName, configuration))
         .orElse(null);
   }
@@ -87,24 +88,25 @@ public static boolean isDefinedExternally(String cacheName) {
    */
   public static <K, V> CacheProxy<K, V> createCache(CacheManager cacheManager,
       String cacheName, Configuration<K, V> configuration) {
-    CaffeineConfiguration<K, V> config = resolveConfigurationFor(configuration);
+    CaffeineConfiguration<K, V> config = resolveConfigurationFor(cacheManager, configuration);
     return new Builder<>(cacheManager, cacheName, config).build();
   }
 
   /** Returns the resolved configuration. */
-  private static Config rootConfig() {
-    return requireNonNull(TypesafeConfigurator.configSource().get());
+  private static Config rootConfig(CacheManager cacheManager) {
+    return requireNonNull(TypesafeConfigurator.configSource().get(
+        cacheManager.getURI(), cacheManager.getClassLoader()));
   }
 
   /** Copies the configuration and overlays it on top of the default settings. */
   @SuppressWarnings("PMD.AccessorMethodGeneration")
   private static <K, V> CaffeineConfiguration<K, V> resolveConfigurationFor(
-      Configuration<K, V> configuration) {
+      CacheManager cacheManager, Configuration<K, V> configuration) {
     if (configuration instanceof CaffeineConfiguration<?, ?>) {
       return new CaffeineConfiguration<>((CaffeineConfiguration<K, V>) configuration);
     }
 
-    CaffeineConfiguration<K, V> template = TypesafeConfigurator.defaults(rootConfig());
+    CaffeineConfiguration<K, V> template = TypesafeConfigurator.defaults(rootConfig(cacheManager));
     if (configuration instanceof CompleteConfiguration<?, ?>) {
       CompleteConfiguration<K, V> complete = (CompleteConfiguration<K, V>) configuration;
       template.setReadThrough(complete.isReadThrough());

jcache/src/main/java/com/github/benmanes/caffeine/jcache/CacheManagerImpl.java

@@ -35,8 +35,6 @@
 
 import org.checkerframework.checker.nullness.qual.Nullable;
 
-import com.github.benmanes.caffeine.jcache.spi.CaffeineCachingProvider;
-
 /**
  * An implementation of JSR-107 {@link CacheManager} that manages Caffeine-based caches.
  *
@@ -55,12 +53,11 @@ public final class CacheManagerImpl implements CacheManager {
 
   private volatile boolean closed;
 
-  public CacheManagerImpl(CachingProvider cacheProvider,
+  public CacheManagerImpl(CachingProvider cacheProvider, boolean runsAsAnOsgiBundle,
       URI uri, ClassLoader classLoader, Properties properties) {
-    this.runsAsAnOsgiBundle = (cacheProvider instanceof CaffeineCachingProvider)
-        && ((CaffeineCachingProvider) cacheProvider).isOsgiComponent();
     this.classLoaderReference = new WeakReference<>(requireNonNull(classLoader));
     this.cacheProvider = requireNonNull(cacheProvider);
+    this.runsAsAnOsgiBundle = runsAsAnOsgiBundle;
     this.properties = requireNonNull(properties);
     this.caches = new ConcurrentHashMap<>();
     this.uri = requireNonNull(uri);
@@ -102,7 +99,7 @@ public <K, V, C extends Configuration<K, V>> Cache<K, V> createCache(
       CacheProxy<?, ?> cache = caches.compute(cacheName, (name, existing) -> {
         if ((existing != null) && !existing.isClosed()) {
           throw new CacheException("Cache " + cacheName + " already exists");
-        } else if (CacheFactory.isDefinedExternally(cacheName)) {
+        } else if (CacheFactory.isDefinedExternally(this, cacheName)) {
           throw new CacheException("Cache " + cacheName + " is configured externally");
         }
         return CacheFactory.createCache(this, cacheName, configuration);

jcache/src/main/java/com/github/benmanes/caffeine/jcache/configuration/ConfigSource.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2023 Ben Manes. All Rights Reserved.
+ *
+ * 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.github.benmanes.caffeine.jcache.configuration;
+
+import java.net.URI;
+
+import com.typesafe.config.Config;
+
+/**
+ * A provider for the external configuration.
+ *
+ * @author ben.manes@gmail.com (Ben Manes)
+ */
+@FunctionalInterface
+public interface ConfigSource {
+
+  /**
+   * Returns a {@link Config} that provides the cache configurations.
+   *
+   * @param uri a uri that may assist in resolve to the resource
+   * @param classloader the classloader to load with
+   * @return a configuration
+   */
+  Config get(URI uri, ClassLoader classloader);
+}

jcache/src/main/java/com/github/benmanes/caffeine/jcache/configuration/TypesafeConfigurator.java

@@ -19,15 +19,18 @@
 import static java.util.concurrent.TimeUnit.MILLISECONDS;
 import static java.util.concurrent.TimeUnit.NANOSECONDS;
 
+import java.io.File;
 import java.lang.System.Logger;
 import java.lang.System.Logger.Level;
+import java.net.URI;
 import java.util.Collections;
 import java.util.Objects;
 import java.util.Optional;
 import java.util.OptionalLong;
 import java.util.Set;
 import java.util.function.Supplier;
 
+import javax.cache.CacheManager;
 import javax.cache.configuration.Factory;
 import javax.cache.configuration.FactoryBuilder;
 import javax.cache.configuration.MutableCacheEntryListenerConfiguration;
@@ -44,6 +47,8 @@
 import com.typesafe.config.Config;
 import com.typesafe.config.ConfigException;
 import com.typesafe.config.ConfigFactory;
+import com.typesafe.config.ConfigParseOptions;
+import com.typesafe.config.ConfigSyntax;
 
 /**
  * Static utility methods pertaining to externalized {@link CaffeineConfiguration} entries using the
@@ -55,8 +60,8 @@
 public final class TypesafeConfigurator {
   static final Logger logger = System.getLogger(TypesafeConfigurator.class.getName());
 
+  static ConfigSource configSource = TypesafeConfigurator::resolveConfig;
   static FactoryCreator factoryCreator = FactoryBuilder::factoryOf;
-  static Supplier<Config> configSource = ConfigFactory::load;
 
   private TypesafeConfigurator() {}
 
@@ -118,21 +123,68 @@ public static void setFactoryCreator(FactoryCreator factoryCreator) {
   }
 
   /**
-   * Specifies how the {@link Config} instance should be loaded. The default strategy uses
-   * {@link ConfigFactory#load()}. The configuration is retrieved on-demand, allowing for it to be
-   * reloaded, and it is assumed that the source caches it as needed.
+   * Specifies how the {@link Config} instance should be loaded. The default strategy uses the uri
+   * provided by {@link CacheManager#getURI()} as an optional override location to parse from a
+   * file system or classpath resource, or else returns {@link ConfigFactory#load(ClassLoader)}.
+   * The configuration is retrieved on-demand, allowing for it to be reloaded, and it is assumed
+   * that the source caches it as needed.
    *
    * @param configSource the strategy for loading the configuration
    */
   public static void setConfigSource(Supplier<Config> configSource) {
+    requireNonNull(configSource);
+    setConfigSource((uri, classloader) -> configSource.get());
+  }
+
+  /**
+   * Specifies how the {@link Config} instance should be loaded. The default strategy uses the uri
+   * provided by {@link CacheManager#getURI()} as an optional override location to parse from a
+   * file system or classpath resource, or else returns {@link ConfigFactory#load(ClassLoader)}.
+   * The configuration is retrieved on-demand, allowing for it to be reloaded, and it is assumed
+   * that the source caches it as needed.
+   *
+   * @param configSource the strategy for loading the configuration from a uri
+   */
+  public static void setConfigSource(ConfigSource configSource) {
     TypesafeConfigurator.configSource = requireNonNull(configSource);
   }
 
   /** Returns the strategy for loading the configuration. */
-  public static Supplier<Config> configSource() {
+  public static ConfigSource configSource() {
     return TypesafeConfigurator.configSource;
   }
 
+  /** Returns the configuration by applying the default strategy. */
+  private static Config resolveConfig(URI uri, ClassLoader classloader) {
+    requireNonNull(uri);
+    requireNonNull(classloader);
+    var options = ConfigParseOptions.defaults().setAllowMissing(false);
+    if ((uri.getScheme() != null) && uri.getScheme().equalsIgnoreCase("file")) {
+      return ConfigFactory.parseFile(new File(uri), options);
+    } else if (isResource(uri)) {
+      return ConfigFactory.parseResources(uri.getSchemeSpecificPart(), options);
+    }
+    return ConfigFactory.load(classloader);
+  }
+
+  /** Returns if the uri is a file or classpath resource. */
+  private static boolean isResource(URI uri) {
+    if ((uri.getScheme() != null) && !uri.getScheme().equalsIgnoreCase("classpath")) {
+      return false;
+    }
+    var path = uri.getSchemeSpecificPart();
+    int dotIndex = path.lastIndexOf('.');
+    if (dotIndex != -1) {
+      var extension = path.substring(dotIndex + 1);
+      for (var format : ConfigSyntax.values()) {
+        if (format.toString().equalsIgnoreCase(extension)) {
+          return true;
+        }
+      }
+    }
+    return false;
+  }
+
   /** A one-shot builder for creating a configuration instance. */
   private static final class Configurator<K, V> {
     final CaffeineConfiguration<K, V> configuration;

jcache/src/main/java/com/github/benmanes/caffeine/jcache/spi/CaffeineCachingProvider.java

@@ -39,9 +39,7 @@
 import org.osgi.service.component.annotations.Component;
 
 import com.github.benmanes.caffeine.jcache.CacheManagerImpl;
-import com.github.benmanes.caffeine.jcache.configuration.TypesafeConfigurator;
 import com.google.errorprone.annotations.concurrent.GuardedBy;
-import com.typesafe.config.ConfigFactory;
 
 /**
  * A provider that produces a JCache implementation backed by Caffeine. Typically, this provider is
@@ -103,7 +101,8 @@ public CacheManager getCacheManager(URI uri, ClassLoader classLoader, Properties
           managerClassLoader, any -> new HashMap<>());
       return cacheManagersByURI.computeIfAbsent(managerURI, any -> {
         Properties managerProperties = (properties == null) ? getDefaultProperties() : properties;
-        return new CacheManagerImpl(this, managerURI, managerClassLoader, managerProperties);
+        return new CacheManagerImpl(this, isOsgiComponent,
+            managerURI, managerClassLoader, managerProperties);
       });
     }
   }
@@ -267,10 +266,5 @@ public Enumeration<URL> getResources(String name) throws IOException {
   @SuppressWarnings("unused")
   private void activate() {
     isOsgiComponent = true;
-    TypesafeConfigurator.setConfigSource(() -> ConfigFactory.load(DEFAULT_CLASS_LOADER));
-  }
-
-  public boolean isOsgiComponent() {
-    return isOsgiComponent;
   }
 }