yang/yang-model-util/src/main/java/org/opendaylight/yangtools/yang/model/repo/util/FilesystemSchemaSourceCache.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.yangtools.yang.model.repo.util;
   9
  10 import static com.google.common.base.Preconditions.checkArgument;
  11 import static java.util.Objects.requireNonNull;
  12 import static org.opendaylight.yangtools.util.concurrent.FluentFutures.immediateFailedFluentFuture;
  13 import static org.opendaylight.yangtools.util.concurrent.FluentFutures.immediateFluentFuture;
  14
  15 import com.google.common.base.MoreObjects.ToStringHelper;
  16 import com.google.common.collect.Lists;
  17 import com.google.common.util.concurrent.FluentFuture;
  18 import java.io.File;
  19 import java.io.FilenameFilter;
  20 import java.io.IOException;
  21 import java.io.InputStream;
  22 import java.nio.file.FileVisitResult;
  23 import java.nio.file.Files;
  24 import java.nio.file.Path;
  25 import java.nio.file.SimpleFileVisitor;
  26 import java.nio.file.StandardCopyOption;
  27 import java.nio.file.attribute.BasicFileAttributes;
  28 import java.time.format.DateTimeParseException;
  29 import java.util.Collections;
  30 import java.util.List;
  31 import java.util.Map;
  32 import java.util.Optional;
  33 import java.util.TreeMap;
  34 import java.util.regex.Matcher;
  35 import java.util.regex.Pattern;
  36 import org.opendaylight.yangtools.yang.common.Revision;
  37 import org.opendaylight.yangtools.yang.model.repo.api.MissingSchemaSourceException;
  38 import org.opendaylight.yangtools.yang.model.repo.api.RevisionSourceIdentifier;
  39 import org.opendaylight.yangtools.yang.model.repo.api.SchemaSourceRepresentation;
  40 import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
  41 import org.opendaylight.yangtools.yang.model.repo.api.YangTextSchemaSource;
  42 import org.opendaylight.yangtools.yang.model.repo.spi.PotentialSchemaSource.Costs;
  43 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistry;
  44 import org.slf4j.Logger;
  45 import org.slf4j.LoggerFactory;
  46
  47 /**
  48  * Cache implementation that stores schemas in form of files under provided folder.
  49  */
  50 public final class FilesystemSchemaSourceCache<T extends SchemaSourceRepresentation>
  51         extends AbstractSchemaSourceCache<T> {
  52
  53     private static final Logger LOG = LoggerFactory.getLogger(FilesystemSchemaSourceCache.class);
  54
  55     // Init storage adapters
  56     private static final Map<Class<? extends SchemaSourceRepresentation>,
  57             StorageAdapter<? extends SchemaSourceRepresentation>> STORAGE_ADAPTERS = Collections.singletonMap(
  58                     YangTextSchemaSource.class, new YangTextSchemaStorageAdapter());
  59
  60     private static final Pattern CACHED_FILE_PATTERN =
  61             Pattern.compile("(?<moduleName>[^@]+)" + "(@(?<revision>" + Revision.STRING_FORMAT_PATTERN + "))?");
  62
  63     private final Class<T> representation;
  64     private final File storageDirectory;
  65
  66     public FilesystemSchemaSourceCache(
  67             final SchemaSourceRegistry consumer, final Class<T> representation, final File storageDirectory) {
  68         super(consumer, representation, Costs.LOCAL_IO);
  69         this.representation = representation;
  70         this.storageDirectory = requireNonNull(storageDirectory);
  71
  72         checkSupportedRepresentation(representation);
  73
  74         checkArgument(storageDirectory.mkdirs() || storageDirectory.isDirectory(),
  75                 "Unable to create cache directory at %s", storageDirectory);
  76         checkArgument(storageDirectory.canWrite());
  77         checkArgument(storageDirectory.canRead());
  78
  79         init();
  80     }
  81
  82     private static void checkSupportedRepresentation(final Class<? extends SchemaSourceRepresentation> representation) {
  83         for (final Class<? extends SchemaSourceRepresentation> supportedRepresentation : STORAGE_ADAPTERS.keySet()) {
  84             if (supportedRepresentation.isAssignableFrom(representation)) {
  85                 return;
  86             }
  87         }
  88
  89         throw new IllegalArgumentException(String.format(
  90                    "This cache does not support representation: %s, supported representations are: %s",
  91                    representation, STORAGE_ADAPTERS.keySet()));
  92     }
  93
  94     /**
  95      * Restore cache state.
  96      */
  97     private void init() {
  98
  99         final CachedModulesFileVisitor fileVisitor = new CachedModulesFileVisitor();
 100         try {
 101             Files.walkFileTree(storageDirectory.toPath(), fileVisitor);
 102         } catch (final IOException e) {
 103             LOG.warn("Unable to restore cache from {}. Starting with empty cache", storageDirectory);
 104             return;
 105         }
 106
 107         for (final SourceIdentifier cachedSchema : fileVisitor.getCachedSchemas()) {
 108             register(cachedSchema);
 109         }
 110     }
 111
 112     @Override
 113     public synchronized FluentFuture<? extends T> getSource(
 114             final SourceIdentifier sourceIdentifier) {
 115         final File file = sourceIdToFile(sourceIdentifier, storageDirectory);
 116         if (file.exists() && file.canRead()) {
 117             LOG.trace("Source {} found in cache as {}", sourceIdentifier, file);
 118             final SchemaSourceRepresentation restored = STORAGE_ADAPTERS.get(representation).restore(sourceIdentifier,
 119                     file);
 120             return immediateFluentFuture(representation.cast(restored));
 121         }
 122
 123         LOG.debug("Source {} not found in cache as {}", sourceIdentifier, file);
 124         return immediateFailedFluentFuture(new MissingSchemaSourceException("Source not found", sourceIdentifier));
 125     }
 126
 127     @Override
 128     protected synchronized void offer(final T source) {
 129         LOG.trace("Source {} offered to cache", source.getIdentifier());
 130         final File file = sourceIdToFile(source);
 131         if (file.exists()) {
 132             LOG.debug("Source {} already in cache as {}", source.getIdentifier(), file);
 133             return;
 134         }
 135
 136         storeSource(file, source);
 137         register(source.getIdentifier());
 138         LOG.trace("Source {} stored in cache as {}", source.getIdentifier(), file);
 139     }
 140
 141     private File sourceIdToFile(final T source) {
 142         return sourceIdToFile(source.getIdentifier(), storageDirectory);
 143     }
 144
 145     static File sourceIdToFile(final SourceIdentifier identifier, final File storageDirectory) {
 146         final Optional<Revision> rev = identifier.getRevision();
 147         final File file;
 148         if (!rev.isPresent()) {
 149             // FIXME: this does not look right
 150             file = findFileWithNewestRev(identifier, storageDirectory);
 151         } else {
 152             file = new File(storageDirectory, identifier.toYangFilename());
 153         }
 154         return file;
 155     }
 156
 157     private static File findFileWithNewestRev(final SourceIdentifier identifier, final File storageDirectory) {
 158         File[] files = storageDirectory.listFiles(new FilenameFilter() {
 159             final Pattern pat = Pattern.compile(Pattern.quote(identifier.getName())
 160                     + "(\\.yang|@\\d\\d\\d\\d-\\d\\d-\\d\\d.yang)");
 161
 162             @Override
 163             public boolean accept(final File dir, final String name) {
 164                 return pat.matcher(name).matches();
 165             }
 166         });
 167
 168         if (files.length == 0) {
 169             return new File(storageDirectory, identifier.toYangFilename());
 170         }
 171         if (files.length == 1) {
 172             return files[0];
 173         }
 174
 175         File file = null;
 176         TreeMap<Optional<Revision>, File> map = new TreeMap<>(Revision::compare);
 177         for (File sorted : files) {
 178             String fileName = sorted.getName();
 179             Matcher match = Revision.STRING_FORMAT_PATTERN.matcher(fileName);
 180             if (match.find()) {
 181                 String revStr = match.group();
 182                 Revision rev;
 183                 try {
 184                     rev = Revision.of(revStr);
 185                 } catch (final DateTimeParseException e) {
 186                     LOG.info("Unable to parse date from yang file name {}, falling back to not-present", fileName, e);
 187                     rev = null;
 188                 }
 189
 190                 map.put(Optional.ofNullable(rev), sorted);
 191
 192             } else {
 193                 map.put(Optional.empty(), sorted);
 194             }
 195         }
 196         file = map.lastEntry().getValue();
 197
 198         return file;
 199     }
 200
 201     private void storeSource(final File file, final T schemaRepresentation) {
 202         STORAGE_ADAPTERS.get(representation).store(file, schemaRepresentation);
 203     }
 204
 205     private abstract static class StorageAdapter<T extends SchemaSourceRepresentation> {
 206
 207         private final Class<T> supportedType;
 208
 209         protected StorageAdapter(final Class<T> supportedType) {
 210             this.supportedType = supportedType;
 211         }
 212
 213         void store(final File file, final SchemaSourceRepresentation schemaSourceRepresentation) {
 214             checkArgument(supportedType.isAssignableFrom(schemaSourceRepresentation.getClass()),
 215                     "Cannot store schema source %s, this adapter only supports %s", schemaSourceRepresentation,
 216                     supportedType);
 217
 218             storeAsType(file, supportedType.cast(schemaSourceRepresentation));
 219         }
 220
 221         protected abstract void storeAsType(File file, T cast);
 222
 223         public T restore(final SourceIdentifier sourceIdentifier, final File cachedSource) {
 224             checkArgument(cachedSource.isFile());
 225             checkArgument(cachedSource.exists());
 226             checkArgument(cachedSource.canRead());
 227             return restoreAsType(sourceIdentifier, cachedSource);
 228         }
 229
 230         protected abstract T restoreAsType(SourceIdentifier sourceIdentifier, File cachedSource);
 231     }
 232
 233     private static final class YangTextSchemaStorageAdapter extends StorageAdapter<YangTextSchemaSource> {
 234
 235         protected YangTextSchemaStorageAdapter() {
 236             super(YangTextSchemaSource.class);
 237         }
 238
 239         @Override
 240         protected void storeAsType(final File file, final YangTextSchemaSource cast) {
 241             try (InputStream castStream = cast.openStream()) {
 242                 Files.copy(castStream, file.toPath(), StandardCopyOption.REPLACE_EXISTING);
 243             } catch (final IOException e) {
 244                 throw new IllegalStateException("Cannot store schema source " + cast.getIdentifier() + " to " + file,
 245                         e);
 246             }
 247         }
 248
 249         @Override
 250         public YangTextSchemaSource restoreAsType(final SourceIdentifier sourceIdentifier, final File cachedSource) {
 251             return new YangTextSchemaSource(sourceIdentifier) {
 252
 253                 @Override
 254                 protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 255                     return toStringHelper;
 256                 }
 257
 258                 @Override
 259                 public InputStream openStream() throws IOException {
 260                     return Files.newInputStream(cachedSource.toPath());
 261                 }
 262             };
 263         }
 264     }
 265
 266     private static final class CachedModulesFileVisitor extends SimpleFileVisitor<Path> {
 267         private final List<SourceIdentifier> cachedSchemas = Lists.newArrayList();
 268
 269         @Override
 270         public FileVisitResult visitFile(final Path file, final BasicFileAttributes attrs) throws IOException {
 271             final FileVisitResult fileVisitResult = super.visitFile(file, attrs);
 272             String fileName = file.toFile().getName();
 273             fileName = com.google.common.io.Files.getNameWithoutExtension(fileName);
 274
 275             final Optional<SourceIdentifier> si = getSourceIdentifier(fileName);
 276             if (si.isPresent()) {
 277                 LOG.trace("Restoring cached file {} as {}", file, si.get());
 278                 cachedSchemas.add(si.get());
 279             } else {
 280                 LOG.debug("Skipping cached file {}, cannot restore source identifier from filename: {},"
 281                         + " does not match {}", file, fileName, CACHED_FILE_PATTERN);
 282             }
 283             return fileVisitResult;
 284         }
 285
 286         private static Optional<SourceIdentifier> getSourceIdentifier(final String fileName) {
 287             final Matcher matcher = CACHED_FILE_PATTERN.matcher(fileName);
 288             if (matcher.matches()) {
 289                 final String moduleName = matcher.group("moduleName");
 290                 final String revision = matcher.group("revision");
 291                 return Optional.of(RevisionSourceIdentifier.create(moduleName, Revision.ofNullable(revision)));
 292             }
 293             return Optional.empty();
 294         }
 295
 296         @Override
 297         public FileVisitResult visitFileFailed(final Path file, final IOException exc) throws IOException {
 298             LOG.warn("Unable to restore cached file {}. Ignoring", file, exc);
 299             return FileVisitResult.CONTINUE;
 300         }
 301
 302         public List<SourceIdentifier> getCachedSchemas() {
 303             return cachedSchemas;
 304         }
 305     }
 306 }