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
  13 import com.google.common.base.MoreObjects.ToStringHelper;
  14 import com.google.common.base.Strings;
  15 import com.google.common.collect.Lists;
  16 import com.google.common.util.concurrent.CheckedFuture;
  17 import com.google.common.util.concurrent.Futures;
  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.text.DateFormat;
  29 import java.text.ParseException;
  30 import java.util.Collections;
  31 import java.util.Date;
  32 import java.util.List;
  33 import java.util.Map;
  34 import java.util.Optional;
  35 import java.util.TreeMap;
  36 import java.util.regex.Matcher;
  37 import java.util.regex.Pattern;
  38 import org.opendaylight.yangtools.yang.common.SimpleDateFormatUtil;
  39 import org.opendaylight.yangtools.yang.model.repo.api.MissingSchemaSourceException;
  40 import org.opendaylight.yangtools.yang.model.repo.api.RevisionSourceIdentifier;
  41 import org.opendaylight.yangtools.yang.model.repo.api.SchemaSourceException;
  42 import org.opendaylight.yangtools.yang.model.repo.api.SchemaSourceRepresentation;
  43 import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
  44 import org.opendaylight.yangtools.yang.model.repo.api.YangTextSchemaSource;
  45 import org.opendaylight.yangtools.yang.model.repo.spi.PotentialSchemaSource.Costs;
  46 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistry;
  47 import org.slf4j.Logger;
  48 import org.slf4j.LoggerFactory;
  49
  50 /**
  51  * Cache implementation that stores schemas in form of files under provided folder.
  52  */
  53 public final class FilesystemSchemaSourceCache<T extends SchemaSourceRepresentation>
  54         extends AbstractSchemaSourceCache<T> {
  55
  56     private static final Logger LOG = LoggerFactory.getLogger(FilesystemSchemaSourceCache.class);
  57
  58     // Init storage adapters
  59     private static final Map<Class<? extends SchemaSourceRepresentation>,
  60             StorageAdapter<? extends SchemaSourceRepresentation>> STORAGE_ADAPTERS = Collections.singletonMap(
  61                     YangTextSchemaSource.class, new YangTextSchemaStorageAdapter());
  62
  63     private static final Pattern CACHED_FILE_PATTERN =
  64             Pattern.compile("(?<moduleName>[^@]+)" + "(@(?<revision>" + SourceIdentifier.REVISION_PATTERN + "))?");
  65
  66     private final Class<T> representation;
  67     private final File storageDirectory;
  68
  69     public FilesystemSchemaSourceCache(
  70             final SchemaSourceRegistry consumer, final Class<T> representation, final File storageDirectory) {
  71         super(consumer, representation, Costs.LOCAL_IO);
  72         this.representation = representation;
  73         this.storageDirectory = requireNonNull(storageDirectory);
  74
  75         checkSupportedRepresentation(representation);
  76
  77         if (!storageDirectory.exists()) {
  78             checkArgument(storageDirectory.mkdirs(), "Unable to create cache directory at %s", storageDirectory);
  79         }
  80         checkArgument(storageDirectory.exists());
  81         checkArgument(storageDirectory.isDirectory());
  82         checkArgument(storageDirectory.canWrite());
  83         checkArgument(storageDirectory.canRead());
  84
  85         init();
  86     }
  87
  88     private static void checkSupportedRepresentation(final Class<? extends SchemaSourceRepresentation> representation) {
  89         for (final Class<? extends SchemaSourceRepresentation> supportedRepresentation : STORAGE_ADAPTERS.keySet()) {
  90             if (supportedRepresentation.isAssignableFrom(representation)) {
  91                 return;
  92             }
  93         }
  94
  95         throw new IllegalArgumentException(String.format(
  96                    "This cache does not support representation: %s, supported representations are: %s",
  97                    representation, STORAGE_ADAPTERS.keySet()));
  98     }
  99
 100     /**
 101      * Restore cache state.
 102      */
 103     private void init() {
 104
 105         final CachedModulesFileVisitor fileVisitor = new CachedModulesFileVisitor();
 106         try {
 107             Files.walkFileTree(storageDirectory.toPath(), fileVisitor);
 108         } catch (final IOException e) {
 109             LOG.warn("Unable to restore cache from {}. Starting with empty cache", storageDirectory);
 110             return;
 111         }
 112
 113         for (final SourceIdentifier cachedSchema : fileVisitor.getCachedSchemas()) {
 114             register(cachedSchema);
 115         }
 116     }
 117
 118     @Override
 119     public synchronized CheckedFuture<? extends T, SchemaSourceException> getSource(
 120             final SourceIdentifier sourceIdentifier) {
 121         final File file = sourceIdToFile(sourceIdentifier, storageDirectory);
 122         if (file.exists() && file.canRead()) {
 123             LOG.trace("Source {} found in cache as {}", sourceIdentifier, file);
 124             final SchemaSourceRepresentation restored = STORAGE_ADAPTERS.get(representation).restore(sourceIdentifier,
 125                     file);
 126             return Futures.immediateCheckedFuture(representation.cast(restored));
 127         }
 128
 129         LOG.debug("Source {} not found in cache as {}", sourceIdentifier, file);
 130         return Futures.immediateFailedCheckedFuture(new MissingSchemaSourceException("Source not found",
 131                     sourceIdentifier));
 132     }
 133
 134     @Override
 135     protected synchronized void offer(final T source) {
 136         LOG.trace("Source {} offered to cache", source.getIdentifier());
 137         final File file = sourceIdToFile(source);
 138         if (file.exists()) {
 139             LOG.debug("Source {} already in cache as {}", source.getIdentifier(), file);
 140             return;
 141         }
 142
 143         storeSource(file, source);
 144         register(source.getIdentifier());
 145         LOG.trace("Source {} stored in cache as {}", source.getIdentifier(), file);
 146     }
 147
 148     private File sourceIdToFile(final T source) {
 149         return sourceIdToFile(source.getIdentifier(), storageDirectory);
 150     }
 151
 152     static File sourceIdToFile(final SourceIdentifier identifier, final File storageDirectory) {
 153         final String rev = identifier.getRevision();
 154         final File file;
 155         if (Strings.isNullOrEmpty(rev)) {
 156             file = findFileWithNewestRev(identifier, storageDirectory);
 157         } else {
 158             file = new File(storageDirectory, identifier.toYangFilename());
 159         }
 160         return file;
 161     }
 162
 163     private static File findFileWithNewestRev(final SourceIdentifier identifier, final File storageDirectory) {
 164         File[] files = storageDirectory.listFiles(new FilenameFilter() {
 165             final Pattern pat = Pattern.compile(Pattern.quote(identifier.getName())
 166                     + "(\\.yang|@\\d\\d\\d\\d-\\d\\d-\\d\\d.yang)");
 167
 168             @Override
 169             public boolean accept(final File dir, final String name) {
 170                 return pat.matcher(name).matches();
 171             }
 172         });
 173
 174         if (files.length == 0) {
 175             return new File(storageDirectory, identifier.toYangFilename());
 176         }
 177         if (files.length == 1) {
 178             return files[0];
 179         }
 180
 181         File file = null;
 182         TreeMap<Date, File> map = new TreeMap<>();
 183         for (File sorted : files) {
 184             String fileName = sorted.getName();
 185             Matcher match = SourceIdentifier.REVISION_PATTERN.matcher(fileName);
 186             if (match.find()) {
 187                 String revStr = match.group();
 188                 /*
 189                  * FIXME: Consider using string for comparison.
 190                  * String is comparable, pattern check tested format
 191                  * so comparing as ASCII string should be sufficient
 192                  */
 193                 DateFormat df = SimpleDateFormatUtil.getRevisionFormat();
 194                 try {
 195                     Date date = df.parse(revStr);
 196                     map.put(date, sorted);
 197                 } catch (final ParseException e) {
 198                     LOG.info("Unable to parse date from yang file name {}", fileName);
 199                     map.put(new Date(0L), sorted);
 200                 }
 201
 202             } else {
 203                 map.put(new Date(0L), sorted);
 204             }
 205         }
 206         file = map.lastEntry().getValue();
 207
 208         return file;
 209     }
 210
 211     private void storeSource(final File file, final T schemaRepresentation) {
 212         STORAGE_ADAPTERS.get(representation).store(file, schemaRepresentation);
 213     }
 214
 215     private abstract static class StorageAdapter<T extends SchemaSourceRepresentation> {
 216
 217         private final Class<T> supportedType;
 218
 219         protected StorageAdapter(final Class<T> supportedType) {
 220             this.supportedType = supportedType;
 221         }
 222
 223         void store(final File file, final SchemaSourceRepresentation schemaSourceRepresentation) {
 224             checkArgument(supportedType.isAssignableFrom(schemaSourceRepresentation.getClass()),
 225                     "Cannot store schema source %s, this adapter only supports %s", schemaSourceRepresentation,
 226                     supportedType);
 227
 228             storeAsType(file, supportedType.cast(schemaSourceRepresentation));
 229         }
 230
 231         protected abstract void storeAsType(File file, T cast);
 232
 233         public T restore(final SourceIdentifier sourceIdentifier, final File cachedSource) {
 234             checkArgument(cachedSource.isFile());
 235             checkArgument(cachedSource.exists());
 236             checkArgument(cachedSource.canRead());
 237             return restoreAsType(sourceIdentifier, cachedSource);
 238         }
 239
 240         protected abstract T restoreAsType(SourceIdentifier sourceIdentifier, File cachedSource);
 241     }
 242
 243     private static final class YangTextSchemaStorageAdapter extends StorageAdapter<YangTextSchemaSource> {
 244
 245         protected YangTextSchemaStorageAdapter() {
 246             super(YangTextSchemaSource.class);
 247         }
 248
 249         @Override
 250         protected void storeAsType(final File file, final YangTextSchemaSource cast) {
 251             try (InputStream castStream = cast.openStream()) {
 252                 Files.copy(castStream, file.toPath(), StandardCopyOption.REPLACE_EXISTING);
 253             } catch (final IOException e) {
 254                 throw new IllegalStateException("Cannot store schema source " + cast.getIdentifier() + " to " + file,
 255                         e);
 256             }
 257         }
 258
 259         @Override
 260         public YangTextSchemaSource restoreAsType(final SourceIdentifier sourceIdentifier, final File cachedSource) {
 261             return new YangTextSchemaSource(sourceIdentifier) {
 262
 263                 @Override
 264                 protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 265                     return toStringHelper;
 266                 }
 267
 268                 @Override
 269                 public InputStream openStream() throws IOException {
 270                     return Files.newInputStream(cachedSource.toPath());
 271                 }
 272             };
 273         }
 274     }
 275
 276     private static final class CachedModulesFileVisitor extends SimpleFileVisitor<Path> {
 277         private final List<SourceIdentifier> cachedSchemas = Lists.newArrayList();
 278
 279         @Override
 280         public FileVisitResult visitFile(final Path file, final BasicFileAttributes attrs) throws IOException {
 281             final FileVisitResult fileVisitResult = super.visitFile(file, attrs);
 282             String fileName = file.toFile().getName();
 283             fileName = com.google.common.io.Files.getNameWithoutExtension(fileName);
 284
 285             final Optional<SourceIdentifier> si = getSourceIdentifier(fileName);
 286             if (si.isPresent()) {
 287                 LOG.trace("Restoring cached file {} as {}", file, si.get());
 288                 cachedSchemas.add(si.get());
 289             } else {
 290                 LOG.debug("Skipping cached file {}, cannot restore source identifier from filename: {},"
 291                         + " does not match {}", file, fileName, CACHED_FILE_PATTERN);
 292             }
 293             return fileVisitResult;
 294         }
 295
 296         private static Optional<SourceIdentifier> getSourceIdentifier(final String fileName) {
 297             final Matcher matcher = CACHED_FILE_PATTERN.matcher(fileName);
 298             if (matcher.matches()) {
 299                 final String moduleName = matcher.group("moduleName");
 300                 final String revision = matcher.group("revision");
 301                 return Optional.of(RevisionSourceIdentifier.create(moduleName, Optional.ofNullable(revision)));
 302             }
 303             return Optional.empty();
 304         }
 305
 306         @Override
 307         public FileVisitResult visitFileFailed(final Path file, final IOException exc) throws IOException {
 308             LOG.warn("Unable to restore cached file {}. Ignoring", file, exc);
 309             return FileVisitResult.CONTINUE;
 310         }
 311
 312         public List<SourceIdentifier> getCachedSchemas() {
 313             return cachedSchemas;
 314         }
 315     }
 316 }