/*
* Copyright (c) 2015 Cisco Systems, Inc. and others. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 which accompanies this distribution,
* and is available at http://www.eclipse.org/legal/epl-v10.html
*/
package org.opendaylight.yangtools.yang.parser.repo;
import static com.google.common.base.Preconditions.checkArgument;
import com.google.common.base.MoreObjects.ToStringHelper;
import com.google.common.base.Optional;
import com.google.common.base.Preconditions;
import com.google.common.collect.ArrayListMultimap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Multimap;
import com.google.common.util.concurrent.CheckedFuture;
import com.google.common.util.concurrent.Futures;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.Collection;
import java.util.Set;
import java.util.concurrent.ConcurrentLinkedDeque;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicReference;
import javax.annotation.Nonnull;
import org.opendaylight.yangtools.yang.model.api.SchemaContext;
import org.opendaylight.yangtools.yang.model.parser.api.YangSyntaxErrorException;
import org.opendaylight.yangtools.yang.model.repo.api.MissingSchemaSourceException;
import org.opendaylight.yangtools.yang.model.repo.api.RevisionSourceIdentifier;
import org.opendaylight.yangtools.yang.model.repo.api.SchemaContextFactory;
import org.opendaylight.yangtools.yang.model.repo.api.SchemaRepository;
import org.opendaylight.yangtools.yang.model.repo.api.SchemaResolutionException;
import org.opendaylight.yangtools.yang.model.repo.api.SchemaSourceException;
import org.opendaylight.yangtools.yang.model.repo.api.SchemaSourceFilter;
import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
import org.opendaylight.yangtools.yang.model.repo.api.StatementParserMode;
import org.opendaylight.yangtools.yang.model.repo.api.YangTextSchemaSource;
import org.opendaylight.yangtools.yang.model.repo.spi.PotentialSchemaSource;
import org.opendaylight.yangtools.yang.model.repo.spi.PotentialSchemaSource.Costs;
import org.opendaylight.yangtools.yang.model.repo.spi.SchemaListenerRegistration;
import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceProvider;
import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistration;
import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistry;
import org.opendaylight.yangtools.yang.model.repo.util.InMemorySchemaSourceCache;
import org.opendaylight.yangtools.yang.parser.util.ASTSchemaSource;
import org.opendaylight.yangtools.yang.parser.util.TextToASTTransformer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public final class YangTextSchemaContextResolver implements AutoCloseable, SchemaSourceProvider<YangTextSchemaSource> {
private static final Logger LOG = LoggerFactory.getLogger(YangTextSchemaContextResolver.class);
private static final long SOURCE_LIFETIME_SECONDS = 60;
private final Collection<SourceIdentifier> requiredSources = new ConcurrentLinkedDeque<>();
private final Multimap<SourceIdentifier, YangTextSchemaSource> texts = ArrayListMultimap.create();
private final AtomicReference<Optional<SchemaContext>> currentSchemaContext =
new AtomicReference<>(Optional.absent());
private final InMemorySchemaSourceCache<ASTSchemaSource> cache;
private final SchemaListenerRegistration transReg;
private final SchemaSourceRegistry registry;
private final SchemaRepository repository;
private volatile Object version = new Object();
private volatile Object contextVersion = version;
private YangTextSchemaContextResolver(final SchemaRepository repository, final SchemaSourceRegistry registry) {
this.repository = Preconditions.checkNotNull(repository);
this.registry = Preconditions.checkNotNull(registry);
final TextToASTTransformer t = TextToASTTransformer.create(repository, registry);
transReg = registry.registerSchemaSourceListener(t);
cache = InMemorySchemaSourceCache.createSoftCache(registry, ASTSchemaSource.class, SOURCE_LIFETIME_SECONDS,
TimeUnit.SECONDS);
}
public static YangTextSchemaContextResolver create(final String name) {
final SharedSchemaRepository sharedRepo = new SharedSchemaRepository(name);
return new YangTextSchemaContextResolver(sharedRepo, sharedRepo);
}
/**
* Register a {@link YangTextSchemaSource}.
*
* @param source YANG text source
* @throws YangSyntaxErrorException When the YANG file is syntactically invalid
* @throws IOException when the URL is not readable
* @throws SchemaSourceException When parsing encounters general error
* @return a YangTextSchemaSourceRegistration
*/
public YangTextSchemaSourceRegistration registerSource(@Nonnull final YangTextSchemaSource source)
throws SchemaSourceException, IOException, YangSyntaxErrorException {
checkArgument(source != null);
final ASTSchemaSource ast = TextToASTTransformer.transformText(source);
LOG.trace("Resolved source {} to source {}", source, ast);
// AST carries an accurate identifier, check if it matches the one supplied by the source. If it
// does not, check how much it differs and emit a warning.
final SourceIdentifier providedId = source.getIdentifier();
final SourceIdentifier parsedId = ast.getIdentifier();
final YangTextSchemaSource text;
if (!parsedId.equals(providedId)) {
if (!parsedId.getName().equals(providedId.getName())) {
LOG.info("Provided module name {} does not match actual text {}, corrected",
providedId.toYangFilename(), parsedId.toYangFilename());
} else {
final String sourceRev = providedId.getRevision();
final String astRev = parsedId.getRevision();
if (sourceRev != null && !SourceIdentifier.NOT_PRESENT_FORMATTED_REVISION.equals(sourceRev)) {
if (!sourceRev.equals(astRev)) {
LOG.info("Provided module revision {} does not match actual text {}, corrected",
providedId.toYangFilename(), parsedId.toYangFilename());
}
} else {
LOG.debug("Expanded module {} to {}", providedId.toYangFilename(), parsedId.toYangFilename());
}
}
text = YangTextSchemaSource.delegateForByteSource(parsedId, source);
} else {
text = source;
}
synchronized (this) {
texts.put(parsedId, text);
LOG.debug("Populated {} with text", parsedId);
final SchemaSourceRegistration<YangTextSchemaSource> reg = registry.registerSchemaSource(this,
PotentialSchemaSource.create(parsedId, YangTextSchemaSource.class, Costs.IMMEDIATE.getValue()));
requiredSources.add(parsedId);
cache.schemaSourceEncountered(ast);
LOG.debug("Added source {} to schema context requirements", parsedId);
version = new Object();
return new AbstractYangTextSchemaSourceRegistration(text) {
@Override
protected void removeRegistration() {
synchronized (YangTextSchemaContextResolver.this) {
requiredSources.remove(parsedId);
LOG.trace("Removed source {} from schema context requirements", parsedId);
version = new Object();
reg.close();
texts.remove(parsedId, text);
}
}
};
}
}
/**
* Register a URL containing a YANG text.
*
* @param url YANG text source URL
* @throws YangSyntaxErrorException When the YANG file is syntactically invalid
* @throws IOException when the URL is not readable
* @throws SchemaSourceException When parsing encounters general error
* @return a YangTextSchemaSourceRegistration for this URL
*/
public YangTextSchemaSourceRegistration registerSource(@Nonnull final URL url) throws SchemaSourceException,
IOException, YangSyntaxErrorException {
checkArgument(url != null, "Supplied URL must not be null");
final String path = url.getPath();
final String fileName = path.substring(path.lastIndexOf('/') + 1);
final SourceIdentifier guessedId = guessSourceIdentifier(fileName);
return registerSource(new YangTextSchemaSource(guessedId) {
@Override
public InputStream openStream() throws IOException {
return url.openStream();
}
@Override
protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
return toStringHelper.add("url", url);
}
});
}
private static SourceIdentifier guessSourceIdentifier(final String fileName) {
try {
return YangTextSchemaSource.identifierFromFilename(fileName);
} catch (IllegalArgumentException e) {
LOG.warn("Invalid file name format in '{}'", fileName, e);
return RevisionSourceIdentifier.create(fileName);
}
}
/**
* Try to parse all currently available yang files and build new schema context.
* @return new schema context iif there is at least 1 yang file registered and
* new schema context was successfully built.
*/
public Optional<SchemaContext> getSchemaContext() {
return getSchemaContext(StatementParserMode.DEFAULT_MODE);
}
/**
* Try to parse all currently available yang files and build new schema context
* in dependence on specified parsing mode.
*
* @param statementParserMode mode of statement parser
* @return new schema context iif there is at least 1 yang file registered and
* new schema context was successfully built.
*/
public Optional<SchemaContext> getSchemaContext(final StatementParserMode statementParserMode) {
final SchemaContextFactory factory = repository.createSchemaContextFactory(SchemaSourceFilter.ALWAYS_ACCEPT);
Optional<SchemaContext> sc;
Object v;
do {
// Spin get stable context version
Object cv;
do {
cv = contextVersion;
sc = currentSchemaContext.get();
if (version == cv) {
return sc;
}
} while (cv != contextVersion);
// Version has been updated
Collection<SourceIdentifier> sources;
do {
v = version;
sources = ImmutableSet.copyOf(requiredSources);
} while (v != version);
while (true) {
final CheckedFuture<SchemaContext, SchemaResolutionException> f = factory.createSchemaContext(sources,
statementParserMode);
try {
sc = Optional.of(f.checkedGet());
break;
} catch (SchemaResolutionException e) {
LOG.info("Failed to fully assemble schema context for {}", sources, e);
sources = e.getResolvedSources();
}
}
LOG.debug("Resolved schema context for {}", sources);
synchronized (this) {
if (contextVersion == cv) {
currentSchemaContext.set(sc);
contextVersion = v;
}
}
} while (version == v);
return sc;
}
@Override
public synchronized CheckedFuture<YangTextSchemaSource, SchemaSourceException> getSource(
final SourceIdentifier sourceIdentifier) {
final Collection<YangTextSchemaSource> ret = texts.get(sourceIdentifier);
LOG.debug("Lookup {} result {}", sourceIdentifier, ret);
if (ret.isEmpty()) {
return Futures.immediateFailedCheckedFuture(new MissingSchemaSourceException(
"URL for " + sourceIdentifier + " not registered", sourceIdentifier));
}
return Futures.immediateCheckedFuture(ret.iterator().next());
}
/**
* Return the set of sources currently available in this resolved.
*
* @return An immutable point-in-time view of available sources.
*/
public synchronized Set<SourceIdentifier> getAvailableSources() {
return ImmutableSet.copyOf(texts.keySet());
}
@Override
public void close() {
transReg.close();
}
}