org.opensaml.saml.metadata.resolver.impl.FilesystemMetadataResolver Maven / Gradle / Ivy
/*
* Licensed to the University Corporation for Advanced Internet Development,
* Inc. (UCAID) under one or more contributor license agreements. See the
* NOTICE file distributed with this work for additional information regarding
* copyright ownership. The UCAID 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.opensaml.saml.metadata.resolver.impl;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.Timer;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import net.shibboleth.utilities.java.support.component.ComponentSupport;
import net.shibboleth.utilities.java.support.logic.Constraint;
import net.shibboleth.utilities.java.support.resolver.ResolverException;
import org.joda.time.DateTime;
import org.joda.time.chrono.ISOChronology;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A metadata provider that pulls metadata from a file on the local filesystem.
*
* This metadata provider periodically checks to see if the read metadata file has changed. The delay between each
* refresh interval is calculated as follows. If no validUntil or cacheDuration is present then the
* {@link #getMaxRefreshDelay()} value is used. Otherwise, the earliest refresh interval of the metadata file is checked
* by looking for the earliest of all the validUntil attributes and cacheDuration attributes. If that refresh interval
* is larger than the max refresh delay then {@link #getMaxRefreshDelay()} is used. If that number is smaller than the
* min refresh delay then {@link #getMinRefreshDelay()} is used. Otherwise the calculated refresh delay multiplied by
* {@link #getRefreshDelayFactor()} is used. By using this factor, the provider will attempt to be refresh before the
* cache actually expires, allowing a some room for error and recovery. Assuming the factor is not exceedingly close to
* 1.0 and a min refresh delay that is not overly large, this refresh will likely occur a few times before the cache
* expires.
*
*/
public class FilesystemMetadataResolver extends AbstractReloadingMetadataResolver {
/** Class logger. */
private final Logger log = LoggerFactory.getLogger(FilesystemMetadataResolver.class);
/** The metadata file. */
@Nonnull private File metadataFile;
/**
* Constructor.
*
* @param metadata the metadata file
*
* @throws ResolverException this exception is no longer thrown
*/
public FilesystemMetadataResolver(@Nonnull final File metadata) throws ResolverException {
super();
setMetadataFile(metadata);
}
/**
* Constructor.
*
* @param metadata the metadata file
* @param backgroundTaskTimer timer used to refresh metadata in the background
*
* @throws ResolverException this exception is no longer thrown
*/
public FilesystemMetadataResolver(@Nullable final Timer backgroundTaskTimer, @Nonnull final File metadata)
throws ResolverException {
super(backgroundTaskTimer);
setMetadataFile(metadata);
}
/**
* Sets the file from which metadata is read.
*
* @param file path to the metadata file
*
* @throws ResolverException this exception is no longer thrown
*/
protected void setMetadataFile(@Nonnull final File file) throws ResolverException {
ComponentSupport.ifInitializedThrowUnmodifiabledComponentException(this);
ComponentSupport.ifDestroyedThrowDestroyedComponentException(this);
metadataFile = Constraint.isNotNull(file, "Metadata file cannot be null");
}
/** {@inheritDoc} */
@Override
protected void doDestroy() {
metadataFile = null;
super.doDestroy();
}
/** {@inheritDoc} */
@Override
protected String getMetadataIdentifier() {
return metadataFile.getAbsolutePath();
}
/** {@inheritDoc} */
@Override
protected byte[] fetchMetadata() throws ResolverException {
try {
validateMetadataFile(metadataFile);
final DateTime metadataUpdateTime =
new DateTime(metadataFile.lastModified(), ISOChronology.getInstanceUTC());
if (getLastRefresh() == null || getLastUpdate() == null || metadataUpdateTime.isAfter(getLastUpdate())) {
return inputstreamToByteArray(new FileInputStream(metadataFile));
}
return null;
} catch (final IOException e) {
final String errMsg = "Unable to read metadata file " + metadataFile.getAbsolutePath();
log.error("{} " + errMsg, getLogPrefix(), e);
throw new ResolverException(errMsg, e);
}
}
/**
* Validate the basic properties of the specified metadata file, for example that it exists;
* that it is a file; and that it is readable.
*
* @param file the file to evaluate
* @throws ResolverException if file does not pass basic properties required of a metadata file
*/
protected void validateMetadataFile(@Nonnull final File file) throws ResolverException {
if (!file.exists()) {
throw new ResolverException("Metadata file '" + file.getAbsolutePath() + "' does not exist");
}
if (!file.isFile()) {
throw new ResolverException("Metadata file '" + file.getAbsolutePath() + "' is not a file");
}
if (!file.canRead()) {
throw new ResolverException("Metadata file '" + file.getAbsolutePath() + "' is not readable");
}
}
}