src/main/java/org/apache/sling/caconfig/management/impl/ConfigurationPersistenceStrategyMultiplexerImpl.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.sling.caconfig.management.impl;

import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.Map;
import java.util.Set;

import org.apache.sling.api.resource.Resource;
import org.apache.sling.api.resource.ResourceResolver;
import org.apache.sling.caconfig.management.multiplexer.ConfigurationPersistenceStrategyMultiplexer;
import org.apache.sling.caconfig.spi.ConfigurationCollectionPersistData;
import org.apache.sling.caconfig.spi.ConfigurationPersistData;
import org.apache.sling.caconfig.spi.ConfigurationPersistenceStrategy2;
import org.apache.sling.commons.osgi.Order;
import org.apache.sling.commons.osgi.RankedServices;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import org.osgi.service.component.annotations.Component;
import org.osgi.service.component.annotations.Reference;
import org.osgi.service.component.annotations.ReferenceCardinality;
import org.osgi.service.component.annotations.ReferencePolicy;
import org.osgi.service.component.annotations.ReferencePolicyOption;

/**
 * Detects all {@link ConfigurationPersistenceStrategy2} implementations in the container
 * and consolidates their result based on service ranking.
 */
@Component(
        service = ConfigurationPersistenceStrategyMultiplexer.class,
        reference = {
            @Reference(
                    name = "configurationPersistenceStrategy",
                    service = ConfigurationPersistenceStrategy2.class,
                    bind = "bindConfigurationPersistenceStrategy",
                    unbind = "unbindConfigurationPersistenceStrategy",
                    cardinality = ReferenceCardinality.MULTIPLE,
                    policy = ReferencePolicy.DYNAMIC,
                    policyOption = ReferencePolicyOption.GREEDY)
        })
public class ConfigurationPersistenceStrategyMultiplexerImpl implements ConfigurationPersistenceStrategyMultiplexer {

    private RankedServices<ConfigurationPersistenceStrategy2> items = new RankedServices<>(Order.DESCENDING);

    protected void bindConfigurationPersistenceStrategy(
            ConfigurationPersistenceStrategy2 configurationPersistenceStrategy, Map<String, Object> props) {
        items.bind(configurationPersistenceStrategy, props);
    }

    protected void unbindConfigurationPersistenceStrategy(
            ConfigurationPersistenceStrategy2 configurationPersistenceStrategy, Map<String, Object> props) {
        items.unbind(configurationPersistenceStrategy, props);
    }

    /**
     * Transform the configuration resource by the first implementation that has an answer.
     */
    @Override
    public Resource getResource(@NotNull Resource resource) {
        for (ConfigurationPersistenceStrategy2 item : items) {
            Resource result = item.getResource(resource);
            if (result != null) {
                return result;
            }
        }
        return null;
    }

    @Override
    public Resource getCollectionParentResource(@NotNull Resource resource) {
        for (ConfigurationPersistenceStrategy2 item : items) {
            Resource result = item.getCollectionParentResource(resource);
            if (result != null) {
                return result;
            }
        }
        return null;
    }

    @Override
    public Resource getCollectionItemResource(@NotNull Resource resource) {
        for (ConfigurationPersistenceStrategy2 item : items) {
            Resource result = item.getCollectionItemResource(resource);
            if (result != null) {
                return result;
            }
        }
        return null;
    }

    @Override
    public String getResourcePath(@NotNull String resourcePath) {
        for (ConfigurationPersistenceStrategy2 item : items) {
            String result = item.getResourcePath(resourcePath);
            if (result != null) {
                return result;
            }
        }
        return null;
    }

    @Override
    public String getCollectionParentResourcePath(@NotNull String resourcePath) {
        for (ConfigurationPersistenceStrategy2 item : items) {
            String result = item.getCollectionParentResourcePath(resourcePath);
            if (result != null) {
                return result;
            }
        }
        return null;
    }

    @Override
    public String getCollectionItemResourcePath(@NotNull String resourcePath) {
        for (ConfigurationPersistenceStrategy2 item : items) {
            String result = item.getCollectionItemResourcePath(resourcePath);
            if (result != null) {
                return result;
            }
        }
        return null;
    }

    @Override
    public String getConfigName(@NotNull String configName, @Nullable String relatedConfigPath) {
        for (ConfigurationPersistenceStrategy2 item : items) {
            String result = item.getConfigName(configName, relatedConfigPath);
            if (result != null) {
                return result;
            }
        }
        return null;
    }

    @Override
    public String getCollectionParentConfigName(@NotNull String configName, @Nullable String relatedConfigPath) {
        for (ConfigurationPersistenceStrategy2 item : items) {
            String result = item.getCollectionParentConfigName(configName, relatedConfigPath);
            if (result != null) {
                return result;
            }
        }
        return null;
    }

    @Override
    public String getCollectionItemConfigName(@NotNull String configName, @Nullable String relatedConfigPath) {
        for (ConfigurationPersistenceStrategy2 item : items) {
            String result = item.getCollectionItemConfigName(configName, relatedConfigPath);
            if (result != null) {
                return result;
            }
        }
        return null;
    }

    @Override
    public @NotNull Collection<String> getAllConfigNames(@NotNull String configName) {
        Set<String> configNames = new LinkedHashSet<>();
        for (ConfigurationPersistenceStrategy2 item : items) {
            String result = item.getConfigName(configName, null);
            if (result != null) {
                configNames.add(result);
            }
        }
        return configNames;
    }

    @Override
    public @NotNull Collection<String> getAllCollectionParentConfigNames(@NotNull String configName) {
        Set<String> configNames = new LinkedHashSet<>();
        for (ConfigurationPersistenceStrategy2 item : items) {
            String result = item.getCollectionParentConfigName(configName, null);
            if (result != null) {
                configNames.add(result);
            }
        }
        return configNames;
    }

    @Override
    public @NotNull Collection<String> getAllCollectionItemConfigNames(@NotNull String configName) {
        Set<String> configNames = new LinkedHashSet<>();
        for (ConfigurationPersistenceStrategy2 item : items) {
            String result = item.getCollectionItemConfigName(configName, null);
            if (result != null) {
                configNames.add(result);
            }
        }
        return configNames;
    }

    /**
     * Persist configuration data with the first implementation that accepts it.
     */
    @Override
    public boolean persistConfiguration(
            @NotNull ResourceResolver resourceResolver,
            @NotNull String configResourcePath,
            @NotNull ConfigurationPersistData data) {
        for (ConfigurationPersistenceStrategy2 item : items) {
            if (item.persistConfiguration(resourceResolver, configResourcePath, data)) {
                return true;
            }
        }
        return false;
    }

    /**
     * Persist configuration data with the first implementation that accepts it.
     */
    @Override
    public boolean persistConfigurationCollection(
            @NotNull ResourceResolver resourceResolver,
            @NotNull String configResourceCollectionParentPath,
            @NotNull ConfigurationCollectionPersistData data) {
        for (ConfigurationPersistenceStrategy2 item : items) {
            if (item.persistConfigurationCollection(resourceResolver, configResourceCollectionParentPath, data)) {
                return true;
            }
        }
        return false;
    }

    @Override
    public boolean deleteConfiguration(@NotNull ResourceResolver resourceResolver, @NotNull String configResourcePath) {
        for (ConfigurationPersistenceStrategy2 item : items) {
            if (item.deleteConfiguration(resourceResolver, configResourcePath)) {
                return true;
            }
        }
        return false;
    }
}