Ejemplo n.º 1
0
  /**
   * Check whether the contents of src and dst are the same.
   *
   * <p>Return false if dstpath does not exist
   *
   * <p>If the files have different sizes, return false.
   *
   * <p>If the files have the same sizes, the file checksums will be compared.
   *
   * <p>When file checksum is not supported in any of file systems, two files are considered as the
   * same if they have the same size.
   */
  private static boolean sameFile(
      FileSystem srcfs, FileStatus srcstatus, FileSystem dstfs, Path dstpath) throws IOException {
    FileStatus dststatus;
    try {
      dststatus = dstfs.getFileStatus(dstpath);
    } catch (FileNotFoundException fnfe) {
      return false;
    }

    // same length?
    if (srcstatus.getLen() != dststatus.getLen()) {
      return false;
    }

    // compare checksums
    try {
      final FileChecksum srccs = srcfs.getFileChecksum(srcstatus.getPath());
      final FileChecksum dstcs = dstfs.getFileChecksum(dststatus.getPath());
      // return true if checksum is not supported
      // (i.e. some of the checksums is null)
      return srccs == null || dstcs == null || srccs.equals(dstcs);
    } catch (FileNotFoundException fnfe) {
      return false;
    }
  }
Ejemplo n.º 2
0
    /**
     * Produce splits such that each is no greater than the quotient of the total size and the
     * number of splits requested.
     *
     * @param job The handle to the JobConf object
     * @param numSplits Number of splits requested
     */
    public InputSplit[] getSplits(JobConf job, int numSplits) throws IOException {
      int cnfiles = job.getInt(SRC_COUNT_LABEL, -1);
      long cbsize = job.getLong(TOTAL_SIZE_LABEL, -1);
      String srcfilelist = job.get(SRC_LIST_LABEL, "");
      if (cnfiles < 0 || cbsize < 0 || "".equals(srcfilelist)) {
        throw new RuntimeException(
            "Invalid metadata: #files("
                + cnfiles
                + ") total_size("
                + cbsize
                + ") listuri("
                + srcfilelist
                + ")");
      }
      Path src = new Path(srcfilelist);
      FileSystem fs = src.getFileSystem(job);
      FileStatus srcst = fs.getFileStatus(src);

      ArrayList<FileSplit> splits = new ArrayList<FileSplit>(numSplits);
      LongWritable key = new LongWritable();
      FilePair value = new FilePair();
      final long targetsize = cbsize / numSplits;
      long pos = 0L;
      long last = 0L;
      long acc = 0L;
      long cbrem = srcst.getLen();
      SequenceFile.Reader sl = null;
      try {
        sl = new SequenceFile.Reader(fs, src, job);
        for (; sl.next(key, value); last = sl.getPosition()) {
          // if adding this split would put this split past the target size,
          // cut the last split and put this next file in the next split.
          if (acc + key.get() > targetsize && acc != 0) {
            long splitsize = last - pos;
            splits.add(new FileSplit(src, pos, splitsize, (String[]) null));
            cbrem -= splitsize;
            pos = last;
            acc = 0L;
          }
          acc += key.get();
        }
      } finally {
        checkAndClose(sl);
      }
      if (cbrem != 0) {
        splits.add(new FileSplit(src, pos, cbrem, (String[]) null));
      }

      return splits.toArray(new FileSplit[splits.size()]);
    }
Ejemplo n.º 3
0
  /**
   * Initialize DFSCopyFileMapper specific job-configuration.
   *
   * @param conf : The dfs/mapred configuration.
   * @param jobConf : The handle to the jobConf object to be initialized.
   * @param args Arguments
   */
  private static void setup(Configuration conf, JobConf jobConf, final Arguments args)
      throws IOException {
    jobConf.set(DST_DIR_LABEL, args.dst.toUri().toString());

    // set boolean values
    final boolean update = args.flags.contains(Options.UPDATE);
    final boolean overwrite = !update && args.flags.contains(Options.OVERWRITE);
    jobConf.setBoolean(Options.UPDATE.propertyname, update);
    jobConf.setBoolean(Options.OVERWRITE.propertyname, overwrite);
    jobConf.setBoolean(
        Options.IGNORE_READ_FAILURES.propertyname,
        args.flags.contains(Options.IGNORE_READ_FAILURES));
    jobConf.setBoolean(
        Options.PRESERVE_STATUS.propertyname, args.flags.contains(Options.PRESERVE_STATUS));

    final String randomId = getRandomId();
    JobClient jClient = new JobClient(jobConf);
    Path jobDirectory = new Path(jClient.getSystemDir(), NAME + "_" + randomId);
    jobConf.set(JOB_DIR_LABEL, jobDirectory.toString());

    FileSystem dstfs = args.dst.getFileSystem(conf);
    boolean dstExists = dstfs.exists(args.dst);
    boolean dstIsDir = false;
    if (dstExists) {
      dstIsDir = dstfs.getFileStatus(args.dst).isDir();
    }

    // default logPath
    Path logPath = args.log;
    if (logPath == null) {
      String filename = "_distcp_logs_" + randomId;
      if (!dstExists || !dstIsDir) {
        Path parent = args.dst.getParent();
        if (!dstfs.exists(parent)) {
          dstfs.mkdirs(parent);
        }
        logPath = new Path(parent, filename);
      } else {
        logPath = new Path(args.dst, filename);
      }
    }
    FileOutputFormat.setOutputPath(jobConf, logPath);

    // create src list, dst list
    FileSystem jobfs = jobDirectory.getFileSystem(jobConf);

    Path srcfilelist = new Path(jobDirectory, "_distcp_src_files");
    jobConf.set(SRC_LIST_LABEL, srcfilelist.toString());
    SequenceFile.Writer src_writer =
        SequenceFile.createWriter(
            jobfs,
            jobConf,
            srcfilelist,
            LongWritable.class,
            FilePair.class,
            SequenceFile.CompressionType.NONE);

    Path dstfilelist = new Path(jobDirectory, "_distcp_dst_files");
    SequenceFile.Writer dst_writer =
        SequenceFile.createWriter(
            jobfs, jobConf, dstfilelist, Text.class, Text.class, SequenceFile.CompressionType.NONE);

    Path dstdirlist = new Path(jobDirectory, "_distcp_dst_dirs");
    jobConf.set(DST_DIR_LIST_LABEL, dstdirlist.toString());
    SequenceFile.Writer dir_writer =
        SequenceFile.createWriter(
            jobfs,
            jobConf,
            dstdirlist,
            Text.class,
            FilePair.class,
            SequenceFile.CompressionType.NONE);

    // handle the case where the destination directory doesn't exist
    // and we've only a single src directory OR we're updating/overwriting
    // the contents of the destination directory.
    final boolean special = (args.srcs.size() == 1 && !dstExists) || update || overwrite;
    int srcCount = 0, cnsyncf = 0, dirsyn = 0;
    long fileCount = 0L, byteCount = 0L, cbsyncs = 0L;
    try {
      for (Iterator<Path> srcItr = args.srcs.iterator(); srcItr.hasNext(); ) {
        final Path src = srcItr.next();
        FileSystem srcfs = src.getFileSystem(conf);
        FileStatus srcfilestat = srcfs.getFileStatus(src);
        Path root = special && srcfilestat.isDir() ? src : src.getParent();
        if (srcfilestat.isDir()) {
          ++srcCount;
        }

        Stack<FileStatus> pathstack = new Stack<FileStatus>();
        for (pathstack.push(srcfilestat); !pathstack.empty(); ) {
          FileStatus cur = pathstack.pop();
          FileStatus[] children = srcfs.listStatus(cur.getPath());
          for (int i = 0; i < children.length; i++) {
            boolean skipfile = false;
            final FileStatus child = children[i];
            final String dst = makeRelative(root, child.getPath());
            ++srcCount;

            if (child.isDir()) {
              pathstack.push(child);
            } else {
              // skip file if the src and the dst files are the same.
              skipfile = update && sameFile(srcfs, child, dstfs, new Path(args.dst, dst));
              // skip file if it exceed file limit or size limit
              skipfile |=
                  fileCount == args.filelimit || byteCount + child.getLen() > args.sizelimit;

              if (!skipfile) {
                ++fileCount;
                byteCount += child.getLen();

                if (LOG.isTraceEnabled()) {
                  LOG.trace("adding file " + child.getPath());
                }

                ++cnsyncf;
                cbsyncs += child.getLen();
                if (cnsyncf > SYNC_FILE_MAX || cbsyncs > BYTES_PER_MAP) {
                  src_writer.sync();
                  dst_writer.sync();
                  cnsyncf = 0;
                  cbsyncs = 0L;
                }
              }
            }

            if (!skipfile) {
              src_writer.append(
                  new LongWritable(child.isDir() ? 0 : child.getLen()), new FilePair(child, dst));
            }

            dst_writer.append(new Text(dst), new Text(child.getPath().toString()));
          }

          if (cur.isDir()) {
            String dst = makeRelative(root, cur.getPath());
            dir_writer.append(new Text(dst), new FilePair(cur, dst));
            if (++dirsyn > SYNC_FILE_MAX) {
              dirsyn = 0;
              dir_writer.sync();
            }
          }
        }
      }
    } finally {
      checkAndClose(src_writer);
      checkAndClose(dst_writer);
      checkAndClose(dir_writer);
    }

    FileStatus dststatus = null;
    try {
      dststatus = dstfs.getFileStatus(args.dst);
    } catch (FileNotFoundException fnfe) {
      LOG.info(args.dst + " does not exist.");
    }

    // create dest path dir if copying > 1 file
    if (dststatus == null) {
      if (srcCount > 1 && !dstfs.mkdirs(args.dst)) {
        throw new IOException("Failed to create" + args.dst);
      }
    }

    final Path sorted = new Path(jobDirectory, "_distcp_sorted");
    checkDuplication(jobfs, dstfilelist, sorted, conf);

    if (dststatus != null && args.flags.contains(Options.DELETE)) {
      deleteNonexisting(dstfs, dststatus, sorted, jobfs, jobDirectory, jobConf, conf);
    }

    Path tmpDir =
        new Path(
            (dstExists && !dstIsDir) || (!dstExists && srcCount == 1)
                ? args.dst.getParent()
                : args.dst,
            "_distcp_tmp_" + randomId);
    jobConf.set(TMP_DIR_LABEL, tmpDir.toUri().toString());
    LOG.info("srcCount=" + srcCount);
    jobConf.setInt(SRC_COUNT_LABEL, srcCount);
    jobConf.setLong(TOTAL_SIZE_LABEL, byteCount);
    setMapCount(byteCount, jobConf);
  }
Ejemplo n.º 4
0
    /**
     * Copy a file to a destination.
     *
     * @param srcstat src path and metadata
     * @param dstpath dst path
     * @param reporter
     */
    private void copy(
        FileStatus srcstat,
        Path relativedst,
        OutputCollector<WritableComparable<?>, Text> outc,
        Reporter reporter)
        throws IOException {
      Path absdst = new Path(destPath, relativedst);
      int totfiles = job.getInt(SRC_COUNT_LABEL, -1);
      assert totfiles >= 0 : "Invalid file count " + totfiles;

      // if a directory, ensure created even if empty
      if (srcstat.isDir()) {
        if (destFileSys.exists(absdst)) {
          if (!destFileSys.getFileStatus(absdst).isDir()) {
            throw new IOException("Failed to mkdirs: " + absdst + " is a file.");
          }
        } else if (!destFileSys.mkdirs(absdst)) {
          throw new IOException("Failed to mkdirs " + absdst);
        }
        // TODO: when modification times can be set, directories should be
        // emitted to reducers so they might be preserved. Also, mkdirs does
        // not currently return an error when the directory already exists;
        // if this changes, all directory work might as well be done in reduce
        return;
      }

      if (destFileSys.exists(absdst) && !overwrite && !needsUpdate(srcstat, destFileSys, absdst)) {
        outc.collect(null, new Text("SKIP: " + srcstat.getPath()));
        ++skipcount;
        reporter.incrCounter(Counter.SKIP, 1);
        updateStatus(reporter);
        return;
      }

      Path tmpfile = new Path(job.get(TMP_DIR_LABEL), relativedst);
      long cbcopied = 0L;
      FSDataInputStream in = null;
      FSDataOutputStream out = null;
      try {
        // open src file
        try {
          in = srcstat.getPath().getFileSystem(job).open(srcstat.getPath());
        } catch (IOException e) {
          LOG.error("Failed to open src file " + srcstat.getPath() + ", ignore and return");
          in = null;
          return;
        }
        reporter.incrCounter(Counter.BYTESEXPECTED, srcstat.getLen());
        // open tmp file
        out = create(tmpfile, reporter, srcstat);
        // copy file
        for (int cbread; (cbread = in.read(buffer)) >= 0; ) {
          out.write(buffer, 0, cbread);
          cbcopied += cbread;
          reporter.setStatus(
              String.format("%.2f ", cbcopied * 100.0 / srcstat.getLen())
                  + absdst
                  + " [ "
                  + StringUtils.humanReadableInt(cbcopied)
                  + " / "
                  + StringUtils.humanReadableInt(srcstat.getLen())
                  + " ]");
        }
      } finally {
        checkAndClose(in);
        checkAndClose(out);
      }

      if (cbcopied != srcstat.getLen()) {
        if (srcstat.getLen() == 0 && cbcopied > 0) {
          LOG.info("most likely see a WAL file corruption: " + srcstat.getPath());
        } else {
          throw new IOException(
              "File size not matched: copied "
                  + bytesString(cbcopied)
                  + " to tmpfile (="
                  + tmpfile
                  + ") but expected "
                  + bytesString(srcstat.getLen())
                  + " from "
                  + srcstat.getPath());
        }
      } else {
        if (totfiles == 1) {
          // Copying a single file; use dst path provided by user as destination
          // rather than destination directory, if a file
          Path dstparent = absdst.getParent();
          if (!(destFileSys.exists(dstparent) && destFileSys.getFileStatus(dstparent).isDir())) {
            absdst = dstparent;
          }
        }
        if (destFileSys.exists(absdst) && destFileSys.getFileStatus(absdst).isDir()) {
          throw new IOException(absdst + " is a directory");
        }
        if (!destFileSys.mkdirs(absdst.getParent())) {
          throw new IOException("Failed to craete parent dir: " + absdst.getParent());
        }
        rename(tmpfile, absdst);

        FileStatus dststat = destFileSys.getFileStatus(absdst);
        if (dststat.getLen() != srcstat.getLen()) {
          destFileSys.delete(absdst, false);
          throw new IOException(
              "File size not matched: copied "
                  + bytesString(dststat.getLen())
                  + " to dst (="
                  + absdst
                  + ") but expected "
                  + bytesString(srcstat.getLen())
                  + " from "
                  + srcstat.getPath());
        }
        updatePermissions(srcstat, dststat);
      }

      // report at least once for each file
      ++copycount;
      reporter.incrCounter(Counter.BYTESCOPIED, cbcopied);
      reporter.incrCounter(Counter.COPY, 1);
      updateStatus(reporter);
    }