/*
* 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 gobblin.runtime.job_catalog;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Collection;
import gobblin.runtime.api.JobCatalog;
import gobblin.runtime.api.JobCatalogWithTemplates;
import gobblin.runtime.api.JobTemplate;
import gobblin.runtime.api.SpecNotFoundException;
import gobblin.runtime.template.ResourceBasedJobTemplate;
import gobblin.util.Decorator;
import lombok.experimental.Delegate;
/**
* A {@link Decorator} for {@link JobCatalog} that loads {@link JobTemplate}s from classpath (resources and classes).
*
* This decorator will intercept {@link JobTemplate} requests with schemes "resource" or "class", and will load them
* from classpath.
* * A class template has uri "class://fully.qualified.class.name", and will instantiate that class and attempt to cast
* as {@link JobTemplate}.
* * A resource template has uri "resource:///path/to/template/in/resources.template", and the decorator will attempt to
* parse it as a {@link ResourceBasedJobTemplate}.
* * Any other scheme will be delegated to the underlying job catalog if it implements {@link JobCatalogWithTemplates},
* or a {@link SpecNotFoundException} will be thrown.
*/
public class PackagedTemplatesJobCatalogDecorator implements Decorator, JobCatalogWithTemplates {
public static final String RESOURCE = "resource";
public static final String CLASS = "class";
/**
* Creates a {@link PackagedTemplatesJobCatalogDecorator} with an underlying empty {@link InMemoryJobCatalog}.
*/
public PackagedTemplatesJobCatalogDecorator() {
this(new InMemoryJobCatalog());
}
@Delegate
private final JobCatalog underlying;
public PackagedTemplatesJobCatalogDecorator(JobCatalog underlying) {
this.underlying = underlying != null ? underlying : new InMemoryJobCatalog();
}
@Override
public Object getDecoratedObject() {
return this.underlying;
}
@Override
public JobTemplate getTemplate(URI uri)
throws SpecNotFoundException, JobTemplate.TemplateException {
if (RESOURCE.equals(uri.getScheme())) {
try {
// resources are accessed by relative uris, make the uri relative (get path, strip initial /)
URI actualResourceUri = new URI(uri.getPath().substring(1));
return ResourceBasedJobTemplate.forURI(actualResourceUri, this);
} catch (URISyntaxException use) {
throw new RuntimeException("Error when computing resource path.", use);
} catch (IOException ioe) {
throw new SpecNotFoundException(uri, ioe);
}
} else if(CLASS.equals(uri.getScheme())) {
try {
return ((Class<? extends JobTemplate>) Class.forName(uri.getAuthority())).newInstance();
} catch (ReflectiveOperationException roe) {
throw new SpecNotFoundException(uri, roe);
}
}
if (this.underlying != null && this.underlying instanceof JobCatalogWithTemplates) {
JobTemplate template = ((JobCatalogWithTemplates) this.underlying).getTemplate(uri);
if (template == null) {
throw new SpecNotFoundException(uri);
}
return template;
}
throw new SpecNotFoundException(uri);
}
@Override
public Collection<JobTemplate> getAllTemplates() {
throw new UnsupportedOperationException();
}
}