fsresource/src/main/java/org/apache/sling/fsprovider/FsResourceProvider.java - sling-samples - Git at Google

 /*
  * 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.fsprovider;

 import java.io.File;
 import java.util.Collections;
 import java.util.Dictionary;
 import java.util.Iterator;
 import java.util.NoSuchElementException;

 import javax.jcr.RepositoryException;
 import javax.jcr.Session;
 import javax.servlet.http.HttpServletRequest;

 import org.apache.sling.api.resource.Resource;
 import org.apache.sling.api.resource.ResourceProvider;
 import org.apache.sling.api.resource.ResourceResolver;
 import org.osgi.framework.BundleContext;
 import org.osgi.service.component.ComponentContext;

 /**
  * The <code>FsResourceProvider</code> is a resource provider which maps
  * filesystem files and folders into the virtual resource tree. The provider is
  * implemented in terms of a component factory, that is multiple instances of
  * this provider may be created by creating respective configuration.
  * <p>
  * Each provider instance is configured with to properties: The location in the
  * resource tree where resources are provided ({@link ResourceProvider#ROOTS})
  * and the file system path from where files and folders are mapped into the
  * resource ({@link #PROP_PROVIDER_FILE}).
  *
  * @scr.component label="%resource.resolver.name"
  *                description="%resource.resolver.description"
  *                factory="org.apache.sling.fsprovider.FsResourceProviderFactory"
  * @scr.service
  * @scr.property name="service.description" value="Sling Filesystem Resource
  *               Provider"
  * @scr.property name="service.vendor" value="The Apache Software Foundation"
  * @scr.property nameRef="ResourceProvider.ROOTS"
  * @scr.property nameRef="PROP_PROVIDER_FILE"
  */
 public class FsResourceProvider implements ResourceProvider {

     /**
      * The name of the configuration property providing file system path of
      * files and folders mapped into the resource tree (value is
      * "provider.file").
      */
     public static final String PROP_PROVIDER_FILE = "provider.file";

     // The location in the resource tree where the resources are mapped
     private String providerRoot;

     // providerRoot + "/" to be used for prefix matching of paths
     private String providerRootPrefix;

     // The "root" file or folder in the file system
     private File providerFile;

     /**
      * Same as {@link #getResource(ResourceResolver, String)}, i.e. the
      * <code>request</code> parameter is ignored.
      *
      * @see #getResource(ResourceResolver, String)
      */
     public Resource getResource(ResourceResolver resourceResolver,
             HttpServletRequest request, String path) {
         return getResource(resourceResolver, path);
     }

     /**
      * Returns a resource wrapping a filesystem file or folder for the given
      * path. If the <code>path</code> is equal to the configured resource tree
      * location of this provider, the configured file system file or folder is
      * used for the resource. Otherwise the configured resource tree location
      * prefix is removed from the path and the remaining relative path is used
      * to access the file or folder. If no such file or folder exists, this
      * method returns <code>null</code>.
      */
     public Resource getResource(ResourceResolver resourceResolver, String path) {
         return getResource(resourceResolver, path, getFile(path));
     }

     /**
      * Returns an iterator of resources.
      */
     public Iterator<Resource> listChildren(Resource parent) {
         File parentFile = parent.adaptTo(File.class);

         // not a FsResource, try to create one from the resource
         if (parentFile == null) {
             // if the parent path is at or below the provider root, get
             // the respective file
             parentFile = getFile(parent.getPath());

             // if the parent path is actually the parent of the provider
             // root, return a single element iterator just containing the
             // provider file, unless the provider file is a directory and
             // a repository item with the same path actually exists
             if (parentFile == null) {

                 String parentPath = parent.getPath().concat("/");
                 if (providerRoot.startsWith(parentPath)) {
                     String relPath = providerRoot.substring(parentPath.length());
                     if (relPath.indexOf('/') < 0) {
                         Resource res = getResource(
                             parent.getResourceResolver(), providerRoot,
                             providerFile);
                         if (res != null) {
                             return Collections.singletonList(res).iterator();
                         }
                     }
                 }

                 // no children here
                 return null;
             }
         }

         if (parentFile != null) {

             final File[] children = parentFile.listFiles();

             if (children != null && children.length > 0) {
                 final ResourceResolver resolver = parent.getResourceResolver();
                 final String parentPath = parent.getPath();
                 return new Iterator<Resource>() {
                     int index = 0;

                     Resource next = seek();

                     public boolean hasNext() {
                         return next != null;
                     }

                     public Resource next() {
                         if (!hasNext()) {
                             throw new NoSuchElementException();
                         }

                         Resource result = next;
                         next = seek();
                         return result;
                     }

                     public void remove() {
                         throw new UnsupportedOperationException("remove");
                     }

                     private Resource seek() {
                         while (index < children.length) {
                             File file = children[index++];
                             String path = parentPath + "/" + file.getName();
                             Resource result = getResource(resolver, path, file);
                             if (result != null) {
                                 return result;
                             }
                         }

                         // nothing found any more
                         return null;
                     }
                 };
             }
         }

         // no children
         return null;
     }

     // ---------- SCR Integration

     protected void activate(ComponentContext context) {
         Dictionary<?, ?> props = context.getProperties();

         String providerRoot = (String) props.get(ROOTS);
         if (providerRoot == null || providerRoot.length() == 0) {
             throw new IllegalArgumentException(ROOTS + " property must be set");
         }

         String providerFileName = (String) props.get(PROP_PROVIDER_FILE);
         if (providerFileName == null || providerFileName.length() == 0) {
             throw new IllegalArgumentException(PROP_PROVIDER_FILE
                 + " property must be set");
         }

         this.providerRoot = providerRoot;
         this.providerRootPrefix = providerRoot.concat("/");
         this.providerFile = getProviderFile(providerFileName,
             context.getBundleContext());
     }

     protected void deactivate(ComponentContext context) {
         this.providerRoot = null;
         this.providerRootPrefix = null;
         this.providerFile = null;
     }

     // ---------- internal

     private File getProviderFile(String providerFileName,
             BundleContext bundleContext) {

         // the file object from the plain name
         File providerFile = new File(providerFileName);

         // resolve relative file name against sling.home or current
         // working directory
         if (!providerFile.isAbsolute()) {
             String home = bundleContext.getProperty("sling.home");
             if (home != null && home.length() > 0) {
                 providerFile = new File(home, providerFileName);
             }
         }

         // resolve the path
         providerFile = providerFile.getAbsoluteFile();

         // if the provider file does not exist, create an empty new folder
         if (!providerFile.exists() && !providerFile.mkdirs()) {
             throw new IllegalArgumentException(
                 "Cannot create provider file root " + providerFile);
         }

         return providerFile;
     }

     /**
      * Returns a file corresponding to the given absolute resource tree path. If
      * the path equals the configured provider root, the provider root file is
      * returned. If the path starts with the configured provider root, a file is
      * returned relative to the provider root file whose relative path is the
      * remains of the resource tree path without the provider root path.
      * Otherwise <code>null</code> is returned.
      */
     private File getFile(String path) {
         if (path.equals(providerRoot)) {
             return providerFile;
         }

         if (path.startsWith(providerRootPrefix)) {
             String relPath = path.substring(providerRootPrefix.length());
             return new File(providerFile, relPath);
         }

         return null;
     }

     private Resource getResource(ResourceResolver resourceResolver,
             String resourcePath, File file) {

         if (file != null) {

             // if the file is a directory, and a repository item exists for
             // the path, do not return the directory here
             if (file.isDirectory()) {
                 Session session = resourceResolver.adaptTo(Session.class);
                 if (session != null) {
                     try {
                         if (session.itemExists(resourcePath)) {
                             return null;
                         }
                     } catch (RepositoryException re) {
                         // don't care
                     }
                 }
             }

             // if the file exists, but is not a directory or no repository entry
             // exists, return it as a resource
             if (file.exists()) {
                 return new FsResource(resourceResolver, resourcePath, file);
             }

         }

         // not applicable or not an existing file path
         return null;
     }
 }
	/*
	* 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.fsprovider;

	import java.io.File;
	import java.util.Collections;
	import java.util.Dictionary;
	import java.util.Iterator;
	import java.util.NoSuchElementException;

	import javax.jcr.RepositoryException;
	import javax.jcr.Session;
	import javax.servlet.http.HttpServletRequest;

	import org.apache.sling.api.resource.Resource;
	import org.apache.sling.api.resource.ResourceProvider;
	import org.apache.sling.api.resource.ResourceResolver;
	import org.osgi.framework.BundleContext;
	import org.osgi.service.component.ComponentContext;

	/**
	* The <code>FsResourceProvider</code> is a resource provider which maps
	* filesystem files and folders into the virtual resource tree. The provider is
	* implemented in terms of a component factory, that is multiple instances of
	* this provider may be created by creating respective configuration.
	* <p>
	* Each provider instance is configured with to properties: The location in the
	* resource tree where resources are provided ({@link ResourceProvider#ROOTS})
	* and the file system path from where files and folders are mapped into the
	* resource ({@link #PROP_PROVIDER_FILE}).
	*
	* @scr.component label="%resource.resolver.name"
	* description="%resource.resolver.description"
	* factory="org.apache.sling.fsprovider.FsResourceProviderFactory"
	* @scr.service
	* @scr.property name="service.description" value="Sling Filesystem Resource
	* Provider"
	* @scr.property name="service.vendor" value="The Apache Software Foundation"
	* @scr.property nameRef="ResourceProvider.ROOTS"
	* @scr.property nameRef="PROP_PROVIDER_FILE"
	*/
	public class FsResourceProvider implements ResourceProvider {

	/**
	* The name of the configuration property providing file system path of
	* files and folders mapped into the resource tree (value is
	* "provider.file").
	*/
	public static final String PROP_PROVIDER_FILE = "provider.file";

	// The location in the resource tree where the resources are mapped
	private String providerRoot;

	// providerRoot + "/" to be used for prefix matching of paths
	private String providerRootPrefix;

	// The "root" file or folder in the file system
	private File providerFile;

	/**
	* Same as {@link #getResource(ResourceResolver, String)}, i.e. the
	* <code>request</code> parameter is ignored.
	*
	* @see #getResource(ResourceResolver, String)
	*/
	public Resource getResource(ResourceResolver resourceResolver,
	HttpServletRequest request, String path) {
	return getResource(resourceResolver, path);
	}

	/**
	* Returns a resource wrapping a filesystem file or folder for the given
	* path. If the <code>path</code> is equal to the configured resource tree
	* location of this provider, the configured file system file or folder is
	* used for the resource. Otherwise the configured resource tree location
	* prefix is removed from the path and the remaining relative path is used
	* to access the file or folder. If no such file or folder exists, this
	* method returns <code>null</code>.
	*/
	public Resource getResource(ResourceResolver resourceResolver, String path) {
	return getResource(resourceResolver, path, getFile(path));
	}

	/**
	* Returns an iterator of resources.
	*/
	public Iterator<Resource> listChildren(Resource parent) {
	File parentFile = parent.adaptTo(File.class);

	// not a FsResource, try to create one from the resource
	if (parentFile == null) {
	// if the parent path is at or below the provider root, get
	// the respective file
	parentFile = getFile(parent.getPath());

	// if the parent path is actually the parent of the provider
	// root, return a single element iterator just containing the
	// provider file, unless the provider file is a directory and
	// a repository item with the same path actually exists
	if (parentFile == null) {

	String parentPath = parent.getPath().concat("/");
	if (providerRoot.startsWith(parentPath)) {
	String relPath = providerRoot.substring(parentPath.length());
	if (relPath.indexOf('/') < 0) {
	Resource res = getResource(
	parent.getResourceResolver(), providerRoot,
	providerFile);
	if (res != null) {
	return Collections.singletonList(res).iterator();
	}
	}
	}

	// no children here
	return null;
	}
	}

	if (parentFile != null) {

	final File[] children = parentFile.listFiles();

	if (children != null && children.length > 0) {
	final ResourceResolver resolver = parent.getResourceResolver();
	final String parentPath = parent.getPath();
	return new Iterator<Resource>() {
	int index = 0;

	Resource next = seek();

	public boolean hasNext() {
	return next != null;
	}

	public Resource next() {
	if (!hasNext()) {
	throw new NoSuchElementException();
	}

	Resource result = next;
	next = seek();
	return result;
	}

	public void remove() {
	throw new UnsupportedOperationException("remove");
	}

	private Resource seek() {
	while (index < children.length) {
	File file = children[index++];
	String path = parentPath + "/" + file.getName();
	Resource result = getResource(resolver, path, file);
	if (result != null) {
	return result;
	}
	}

	// nothing found any more
	return null;
	}
	};
	}
	}

	// no children
	return null;
	}

	// ---------- SCR Integration

	protected void activate(ComponentContext context) {
	Dictionary<?, ?> props = context.getProperties();

	String providerRoot = (String) props.get(ROOTS);
	if (providerRoot == null \|\| providerRoot.length() == 0) {
	throw new IllegalArgumentException(ROOTS + " property must be set");
	}

	String providerFileName = (String) props.get(PROP_PROVIDER_FILE);
	if (providerFileName == null \|\| providerFileName.length() == 0) {
	throw new IllegalArgumentException(PROP_PROVIDER_FILE
	+ " property must be set");
	}

	this.providerRoot = providerRoot;
	this.providerRootPrefix = providerRoot.concat("/");
	this.providerFile = getProviderFile(providerFileName,
	context.getBundleContext());
	}

	protected void deactivate(ComponentContext context) {
	this.providerRoot = null;
	this.providerRootPrefix = null;
	this.providerFile = null;
	}

	// ---------- internal

	private File getProviderFile(String providerFileName,
	BundleContext bundleContext) {

	// the file object from the plain name
	File providerFile = new File(providerFileName);

	// resolve relative file name against sling.home or current
	// working directory
	if (!providerFile.isAbsolute()) {
	String home = bundleContext.getProperty("sling.home");
	if (home != null && home.length() > 0) {
	providerFile = new File(home, providerFileName);
	}
	}

	// resolve the path
	providerFile = providerFile.getAbsoluteFile();

	// if the provider file does not exist, create an empty new folder
	if (!providerFile.exists() && !providerFile.mkdirs()) {
	throw new IllegalArgumentException(
	"Cannot create provider file root " + providerFile);
	}

	return providerFile;
	}

	/**
	* Returns a file corresponding to the given absolute resource tree path. If
	* the path equals the configured provider root, the provider root file is
	* returned. If the path starts with the configured provider root, a file is
	* returned relative to the provider root file whose relative path is the
	* remains of the resource tree path without the provider root path.
	* Otherwise <code>null</code> is returned.
	*/
	private File getFile(String path) {
	if (path.equals(providerRoot)) {
	return providerFile;
	}

	if (path.startsWith(providerRootPrefix)) {
	String relPath = path.substring(providerRootPrefix.length());
	return new File(providerFile, relPath);
	}

	return null;
	}

	private Resource getResource(ResourceResolver resourceResolver,
	String resourcePath, File file) {

	if (file != null) {

	// if the file is a directory, and a repository item exists for
	// the path, do not return the directory here
	if (file.isDirectory()) {
	Session session = resourceResolver.adaptTo(Session.class);
	if (session != null) {
	try {
	if (session.itemExists(resourcePath)) {
	return null;
	}
	} catch (RepositoryException re) {
	// don't care
	}
	}
	}

	// if the file exists, but is not a directory or no repository entry
	// exists, return it as a resource
	if (file.exists()) {
	return new FsResource(resourceResolver, resourcePath, file);
	}

	}

	// not applicable or not an existing file path
	return null;
	}
	}