/*
* Copyright (c) 2014, Francis Galiegue (fgaliegue@gmail.com)
*
* This software is dual-licensed under:
*
* - the Lesser General Public License (LGPL) version 3.0 or, at your option, any
* later version;
* - the Apache Software License (ASL) version 2.0.
*
* The text of this file and of both licenses is available at the root of this
* project or, if you have the jar distribution, in directory META-INF/, under
* the names LGPL-3.0.txt and ASL-2.0.txt respectively.
*
* Direct link to the sources:
*
* - LGPL 3.0: https://www.gnu.org/licenses/lgpl-3.0.txt
* - ASL 2.0: http://www.apache.org/licenses/LICENSE-2.0.txt
*/
package com.github.fge.jsonschema.processors.validation;
import com.github.fge.jsonschema.cfg.ValidationConfiguration;
import com.github.fge.jsonschema.core.exceptions.ProcessingException;
import com.github.fge.jsonschema.core.keyword.syntax.SyntaxProcessor;
import com.github.fge.jsonschema.core.load.RefResolver;
import com.github.fge.jsonschema.core.processing.CachingProcessor;
import com.github.fge.jsonschema.core.processing.Processor;
import com.github.fge.jsonschema.core.processing.ProcessorChain;
import com.github.fge.jsonschema.core.report.ListProcessingReport;
import com.github.fge.jsonschema.core.report.ProcessingReport;
import com.github.fge.jsonschema.core.tree.SchemaTree;
import com.github.fge.jsonschema.core.util.ValueHolder;
import com.github.fge.jsonschema.library.Library;
import com.github.fge.jsonschema.processors.build.ValidatorBuilder;
import com.github.fge.jsonschema.processors.data.SchemaContext;
import com.github.fge.jsonschema.processors.data.ValidatorList;
import com.github.fge.jsonschema.processors.digest.SchemaDigester;
import com.github.fge.jsonschema.processors.format.FormatProcessor;
import com.google.common.base.Equivalence;
import javax.annotation.ParametersAreNonnullByDefault;
/**
* A validation chain
*
* <p>This processor performs the following:</p>
*
* <ul>
* <li>perform reference lookup then syntax validation;</li>
* <li>throw an exception if the previous step fails;</li>
* <li>then perform schema digesting and keyword building.</li>
* </ul>
*
* <p>A validation chain handles one schema version. Switching schema versions
* is done by {@link ValidationProcessor}.</p>
*/
public final class ValidationChain
implements Processor<SchemaContext, ValidatorList>
{
private final Processor<ValueHolder<SchemaTree>, ValueHolder<SchemaTree>>
resolver;
private final Processor<SchemaContext, ValidatorList> builder;
public ValidationChain(final RefResolver refResolver,
final Library library, final ValidationConfiguration cfg)
{
final SyntaxProcessor syntaxProcessor = new SyntaxProcessor(
cfg.getSyntaxMessages(), library.getSyntaxCheckers());
final ProcessorChain<ValueHolder<SchemaTree>, ValueHolder<SchemaTree>>
chain1
= ProcessorChain.startWith(refResolver).chainWith(syntaxProcessor);
resolver = new CachingProcessor<ValueHolder<SchemaTree>, ValueHolder<SchemaTree>>(
chain1.getProcessor(), SchemaHolderEquivalence.INSTANCE
);
final SchemaDigester digester = new SchemaDigester(library);
final ValidatorBuilder keywordBuilder = new ValidatorBuilder(library);
ProcessorChain<SchemaContext, ValidatorList> chain2
= ProcessorChain.startWith(digester).chainWith(keywordBuilder);
if (cfg.getUseFormat()) {
final FormatProcessor format = new FormatProcessor(library, cfg);
chain2 = chain2.chainWith(format);
}
builder = new CachingProcessor<SchemaContext, ValidatorList>(
chain2.getProcessor(), SchemaContextEquivalence.getInstance()
);
}
@Override
public ValidatorList process(final ProcessingReport report,
final SchemaContext input)
throws ProcessingException
{
final ValueHolder<SchemaTree> in
= ValueHolder.hold("schema", input.getSchema());
/*
* We have to go through an intermediate report. If we re-enter this
* function with a report already telling there is an error, we don't
* want to wrongly report that the schema is invalid.
*/
final ProcessingReport r = new ListProcessingReport(report);
final ValueHolder<SchemaTree> out = resolver.process(r, in);
report.mergeWith(r);
if (!r.isSuccess())
return null;
final SchemaContext output = new SchemaContext(out.getValue(),
input.getInstanceType());
return builder.process(report, output);
}
@Override
public String toString()
{
return resolver + " -> " + builder;
}
@ParametersAreNonnullByDefault
private static final class SchemaHolderEquivalence
extends Equivalence<ValueHolder<SchemaTree>>
{
private static final Equivalence<ValueHolder<SchemaTree>> INSTANCE
= new SchemaHolderEquivalence();
@Override
protected boolean doEquivalent(final ValueHolder<SchemaTree> a,
final ValueHolder<SchemaTree> b)
{
return a.getValue().equals(b.getValue());
}
@Override
protected int doHash(final ValueHolder<SchemaTree> t)
{
return t.getValue().hashCode();
}
}
}