yang/yang-repo-fs/src/main/java/org/opendaylight/yangtools/yang/model/repo/fs/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.fs;
   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.util.concurrent.FluentFuture;
  16 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
  17 import java.io.File;
  18 import java.io.FilenameFilter;
  19 import java.io.IOException;
  20 import java.io.InputStream;
  21 import java.nio.file.FileVisitResult;
  22 import java.nio.file.Files;
  23 import java.nio.file.Path;
  24 import java.nio.file.SimpleFileVisitor;
  25 import java.nio.file.StandardCopyOption;
  26 import java.nio.file.attribute.BasicFileAttributes;
  27 import java.time.format.DateTimeParseException;
  28 import java.util.ArrayList;
  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.AbstractSchemaSourceCache;
  43 import org.opendaylight.yangtools.yang.model.repo.spi.PotentialSchemaSource.Costs;
  44 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistry;
  45 import org.slf4j.Logger;
  46 import org.slf4j.LoggerFactory;
  47
  48 /**
  49  * Cache implementation that stores schemas in form of files under provided folder.
  50  */
  51 public final class FilesystemSchemaSourceCache<T extends SchemaSourceRepresentation>
  52         extends AbstractSchemaSourceCache<T> {
  53
  54     private static final Logger LOG = LoggerFactory.getLogger(FilesystemSchemaSourceCache.class);
  55
  56     // Init storage adapters
  57     private static final Map<Class<? extends SchemaSourceRepresentation>,
  58             StorageAdapter<? extends SchemaSourceRepresentation>> STORAGE_ADAPTERS = Collections.singletonMap(
  59                     YangTextSchemaSource.class, new YangTextSchemaStorageAdapter());
  60
  61     private static final Pattern CACHED_FILE_PATTERN =
  62             Pattern.compile("(?<moduleName>[^@]+)" + "(@(?<revision>" + Revision.STRING_FORMAT_PATTERN + "))?");
  63
  64     private final Class<T> representation;
  65     private final File storageDirectory;
  66
  67     public FilesystemSchemaSourceCache(
  68             final SchemaSourceRegistry consumer, final Class<T> representation, final File storageDirectory) {
  69         super(consumer, representation, Costs.LOCAL_IO);
  70         this.representation = representation;
  71         this.storageDirectory = requireNonNull(storageDirectory);
  72
  73         checkSupportedRepresentation(representation);
  74
  75         checkArgument(storageDirectory.mkdirs() || storageDirectory.isDirectory(),
  76                 "Unable to create cache directory at %s", storageDirectory);
  77         checkArgument(storageDirectory.canWrite());
  78         checkArgument(storageDirectory.canRead());
  79
  80         init();
  81     }
  82
  83     private static void checkSupportedRepresentation(final Class<? extends SchemaSourceRepresentation> representation) {
  84         for (final Class<? extends SchemaSourceRepresentation> supportedRepresentation : STORAGE_ADAPTERS.keySet()) {
  85             if (supportedRepresentation.isAssignableFrom(representation)) {
  86                 return;
  87             }
  88         }
  89
  90         throw new IllegalArgumentException(String.format(
  91                    "This cache does not support representation: %s, supported representations are: %s",
  92                    representation, STORAGE_ADAPTERS.keySet()));
  93     }
  94
  95     /**
  96      * Restore cache state.
  97      */
  98     private void init() {
  99
 100         final CachedModulesFileVisitor fileVisitor = new CachedModulesFileVisitor();
 101         try {
 102             Files.walkFileTree(storageDirectory.toPath(), fileVisitor);
 103         } catch (final IOException e) {
 104             LOG.warn("Unable to restore cache from {}. Starting with an empty cache", storageDirectory, e);
 105             return;
 106         }
 107
 108         fileVisitor.getCachedSchemas().stream().forEach(this::register);
 109     }
 110
 111     @Override
 112     public synchronized FluentFuture<? extends T> getSource(final SourceIdentifier sourceIdentifier) {
 113         final File file = sourceIdToFile(sourceIdentifier, storageDirectory);
 114         if (file.exists() && file.canRead()) {
 115             LOG.trace("Source {} found in cache as {}", sourceIdentifier, file);
 116             final SchemaSourceRepresentation restored = STORAGE_ADAPTERS.get(representation).restore(sourceIdentifier,
 117                     file);
 118             return immediateFluentFuture(representation.cast(restored));
 119         }
 120
 121         LOG.debug("Source {} not found in cache as {}", sourceIdentifier, file);
 122         return immediateFailedFluentFuture(new MissingSchemaSourceException("Source not found", sourceIdentifier));
 123     }
 124
 125     @Override
 126     protected synchronized void offer(final T source) {
 127         LOG.trace("Source {} offered to cache", source.getIdentifier());
 128         final File file = sourceIdToFile(source);
 129         if (file.exists()) {
 130             LOG.debug("Source {} already in cache as {}", source.getIdentifier(), file);
 131             return;
 132         }
 133
 134         storeSource(file, source);
 135         register(source.getIdentifier());
 136         LOG.trace("Source {} stored in cache as {}", source.getIdentifier(), file);
 137     }
 138
 139     private File sourceIdToFile(final T source) {
 140         return sourceIdToFile(source.getIdentifier(), storageDirectory);
 141     }
 142
 143     static File sourceIdToFile(final SourceIdentifier identifier, final File storageDirectory) {
 144         final Optional<Revision> rev = identifier.getRevision();
 145         final File file;
 146         if (rev.isEmpty()) {
 147             // FIXME: this does not look right
 148             file = findFileWithNewestRev(identifier, storageDirectory);
 149         } else {
 150             file = new File(storageDirectory, identifier.toYangFilename());
 151         }
 152         return file;
 153     }
 154
 155     @SuppressFBWarnings(value = "NP_NULL_ON_SOME_PATH_FROM_RETURN_VALUE",
 156             justification = "listFiles is analyzed to return null")
 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         // FIXME: use java.nio.filePath
 222         protected abstract void storeAsType(File file, T cast);
 223
 224         T restore(final SourceIdentifier sourceIdentifier, final File cachedSource) {
 225             checkArgument(cachedSource.isFile());
 226             checkArgument(cachedSource.exists());
 227             checkArgument(cachedSource.canRead());
 228             return restoreAsType(sourceIdentifier, cachedSource);
 229         }
 230
 231         abstract T restoreAsType(SourceIdentifier sourceIdentifier, File cachedSource);
 232     }
 233
 234     private static final class YangTextSchemaStorageAdapter extends StorageAdapter<YangTextSchemaSource> {
 235
 236         protected YangTextSchemaStorageAdapter() {
 237             super(YangTextSchemaSource.class);
 238         }
 239
 240         @Override
 241         @SuppressFBWarnings(value = "RCN_REDUNDANT_NULLCHECK_WOULD_HAVE_BEEN_A_NPE",
 242             justification = "https://github.com/spotbugs/spotbugs/issues/600")
 243         protected void storeAsType(final File file, final YangTextSchemaSource cast) {
 244             try (InputStream castStream = cast.openStream()) {
 245                 Files.copy(castStream, file.toPath(), StandardCopyOption.REPLACE_EXISTING);
 246             } catch (final IOException e) {
 247                 throw new IllegalStateException("Cannot store schema source " + cast.getIdentifier() + " to " + file,
 248                         e);
 249             }
 250         }
 251
 252         @Override
 253         YangTextSchemaSource restoreAsType(final SourceIdentifier sourceIdentifier, final File cachedSource) {
 254             return YangTextSchemaSource.forPath(cachedSource.toPath(), sourceIdentifier);
 255         }
 256     }
 257
 258     private static final class CachedModulesFileVisitor extends SimpleFileVisitor<Path> {
 259         private final List<SourceIdentifier> cachedSchemas = new ArrayList<>();
 260
 261         @Override
 262         public FileVisitResult visitFile(final Path file, final BasicFileAttributes attrs) throws IOException {
 263             final FileVisitResult fileVisitResult = super.visitFile(file, attrs);
 264             String fileName = file.toFile().getName();
 265             fileName = com.google.common.io.Files.getNameWithoutExtension(fileName);
 266
 267             final Optional<SourceIdentifier> si = getSourceIdentifier(fileName);
 268             if (si.isPresent()) {
 269                 LOG.trace("Restoring cached file {} as {}", file, si.get());
 270                 cachedSchemas.add(si.get());
 271             } else {
 272                 LOG.debug("Skipping cached file {}, cannot restore source identifier from filename: {},"
 273                         + " does not match {}", file, fileName, CACHED_FILE_PATTERN);
 274             }
 275             return fileVisitResult;
 276         }
 277
 278         private static Optional<SourceIdentifier> getSourceIdentifier(final String fileName) {
 279             final Matcher matcher = CACHED_FILE_PATTERN.matcher(fileName);
 280             if (matcher.matches()) {
 281                 final String moduleName = matcher.group("moduleName");
 282                 final String revision = matcher.group("revision");
 283                 return Optional.of(RevisionSourceIdentifier.create(moduleName, Revision.ofNullable(revision)));
 284             }
 285             return Optional.empty();
 286         }
 287
 288         @Override
 289         public FileVisitResult visitFileFailed(final Path file, final IOException exc) throws IOException {
 290             LOG.warn("Unable to restore cached file {}. Ignoring", file, exc);
 291             return FileVisitResult.CONTINUE;
 292         }
 293
 294         public List<SourceIdentifier> getCachedSchemas() {
 295             return cachedSchemas;
 296         }
 297     }
 298 }