public void streamBlockInAscii( InetSocketAddress addr, long blockId, Token<BlockTokenIdentifier> accessToken, long genStamp, long blockSize, long offsetIntoBlock, long chunkSizeToView, JspWriter out, Configuration conf) throws IOException { if (chunkSizeToView == 0) return; Socket s = new Socket(); s.connect(addr, HdfsConstants.READ_TIMEOUT); s.setSoTimeout(HdfsConstants.READ_TIMEOUT); long amtToRead = Math.min(chunkSizeToView, blockSize - offsetIntoBlock); // Use the block name for file name. BlockReader blockReader = RemoteBlockReader.newBlockReader( s, addr.toString() + ":" + blockId, blockId, accessToken, genStamp, offsetIntoBlock, amtToRead, conf.getInt("io.file.buffer.size", 4096)); byte[] buf = new byte[(int) amtToRead]; int readOffset = 0; int retries = 2; while (amtToRead > 0) { int numRead; try { numRead = blockReader.readAll(buf, readOffset, (int) amtToRead); } catch (IOException e) { retries--; if (retries == 0) throw new IOException("Could not read data from datanode"); continue; } amtToRead -= numRead; readOffset += numRead; } blockReader = null; s.close(); out.print(HtmlQuoting.quoteHtmlChars(new String(buf))); }
public void generateFileChunks(JspWriter out, HttpServletRequest req, Configuration conf) throws IOException, InterruptedException { long startOffset = 0; int datanodePort = 0; int chunkSizeToView = 0; String namenodeInfoPortStr = req.getParameter("namenodeInfoPort"); int namenodeInfoPort = -1; if (namenodeInfoPortStr != null) namenodeInfoPort = Integer.parseInt(namenodeInfoPortStr); String filename = HtmlQuoting.unquoteHtmlChars(req.getParameter("filename")); if (filename == null) { out.print("Invalid input (filename absent)"); return; } String blockIdStr = null; long blockId = 0; blockIdStr = req.getParameter("blockId"); if (blockIdStr == null) { out.print("Invalid input (blockId absent)"); return; } blockId = Long.parseLong(blockIdStr); String tokenString = req.getParameter(JspHelper.DELEGATION_PARAMETER_NAME); UserGroupInformation ugi = JspHelper.getUGI(req, conf); final DFSClient dfs = JspHelper.getDFSClient(ugi, jspHelper.nameNodeAddr, conf); Token<BlockTokenIdentifier> accessToken = BlockTokenSecretManager.DUMMY_TOKEN; if (conf.getBoolean(DFSConfigKeys.DFS_BLOCK_ACCESS_TOKEN_ENABLE_KEY, false)) { List<LocatedBlock> blks = dfs.namenode.getBlockLocations(filename, 0, Long.MAX_VALUE).getLocatedBlocks(); if (blks == null || blks.size() == 0) { out.print("Can't locate file blocks"); dfs.close(); return; } for (int i = 0; i < blks.size(); i++) { if (blks.get(i).getBlock().getBlockId() == blockId) { accessToken = blks.get(i).getBlockToken(); break; } } } String blockGenStamp = null; long genStamp = 0; blockGenStamp = req.getParameter("genstamp"); if (blockGenStamp == null) { out.print("Invalid input (genstamp absent)"); return; } genStamp = Long.parseLong(blockGenStamp); String blockSizeStr; long blockSize = 0; blockSizeStr = req.getParameter("blockSize"); if (blockSizeStr == null) { out.print("Invalid input (blockSize absent)"); return; } blockSize = Long.parseLong(blockSizeStr); String chunkSizeToViewStr = req.getParameter("chunkSizeToView"); if (chunkSizeToViewStr != null && Integer.parseInt(chunkSizeToViewStr) > 0) chunkSizeToView = Integer.parseInt(chunkSizeToViewStr); else chunkSizeToView = JspHelper.getDefaultChunkSize(conf); String startOffsetStr = req.getParameter("startOffset"); if (startOffsetStr == null || Long.parseLong(startOffsetStr) < 0) startOffset = 0; else startOffset = Long.parseLong(startOffsetStr); String datanodePortStr = req.getParameter("datanodePort"); if (datanodePortStr == null) { out.print("Invalid input (datanodePort absent)"); return; } datanodePort = Integer.parseInt(datanodePortStr); out.print("<h3>File: "); JspHelper.printPathWithLinks( HtmlQuoting.quoteHtmlChars(filename), out, namenodeInfoPort, tokenString); out.print("</h3><hr>"); String parent = new File(filename).getParent(); JspHelper.printGotoForm(out, namenodeInfoPort, tokenString, HtmlQuoting.quoteHtmlChars(parent)); out.print("<hr>"); out.print( "<a href=\"http://" + req.getServerName() + ":" + req.getServerPort() + "/browseDirectory.jsp?dir=" + URLEncoder.encode(parent, "UTF-8") + "&namenodeInfoPort=" + namenodeInfoPort + "\"><i>Go back to dir listing</i></a><br>"); out.print("<a href=\"#viewOptions\">Advanced view/download options</a><br>"); out.print("<hr>"); // Determine the prev & next blocks long nextStartOffset = 0; long nextBlockSize = 0; String nextBlockIdStr = null; String nextGenStamp = null; String nextHost = req.getServerName(); int nextPort = req.getServerPort(); int nextDatanodePort = datanodePort; // determine data for the next link if (startOffset + chunkSizeToView >= blockSize) { // we have to go to the next block from this point onwards List<LocatedBlock> blocks = dfs.namenode.getBlockLocations(filename, 0, Long.MAX_VALUE).getLocatedBlocks(); for (int i = 0; i < blocks.size(); i++) { if (blocks.get(i).getBlock().getBlockId() == blockId) { if (i != blocks.size() - 1) { LocatedBlock nextBlock = blocks.get(i + 1); nextBlockIdStr = Long.toString(nextBlock.getBlock().getBlockId()); nextGenStamp = Long.toString(nextBlock.getBlock().getGenerationStamp()); nextStartOffset = 0; nextBlockSize = nextBlock.getBlock().getNumBytes(); DatanodeInfo d = jspHelper.bestNode(nextBlock); String datanodeAddr = d.getName(); nextDatanodePort = Integer.parseInt( datanodeAddr.substring(datanodeAddr.indexOf(':') + 1, datanodeAddr.length())); nextHost = InetAddress.getByName(d.getHost()).getCanonicalHostName(); nextPort = d.getInfoPort(); } } } } else { // we are in the same block nextBlockIdStr = blockIdStr; nextStartOffset = startOffset + chunkSizeToView; nextBlockSize = blockSize; nextGenStamp = blockGenStamp; } String nextUrl = null; if (nextBlockIdStr != null) { nextUrl = "http://" + nextHost + ":" + nextPort + "/browseBlock.jsp?blockId=" + nextBlockIdStr + "&blockSize=" + nextBlockSize + "&startOffset=" + nextStartOffset + "&genstamp=" + nextGenStamp + "&filename=" + URLEncoder.encode(filename, "UTF-8") + "&chunkSizeToView=" + chunkSizeToView + "&datanodePort=" + nextDatanodePort + "&namenodeInfoPort=" + namenodeInfoPort + JspHelper.getDelegationTokenUrlParam(tokenString); out.print("<a href=\"" + nextUrl + "\">View Next chunk</a> "); } // determine data for the prev link String prevBlockIdStr = null; String prevGenStamp = null; long prevStartOffset = 0; long prevBlockSize = 0; String prevHost = req.getServerName(); int prevPort = req.getServerPort(); int prevDatanodePort = datanodePort; if (startOffset == 0) { List<LocatedBlock> blocks = dfs.namenode.getBlockLocations(filename, 0, Long.MAX_VALUE).getLocatedBlocks(); for (int i = 0; i < blocks.size(); i++) { if (blocks.get(i).getBlock().getBlockId() == blockId) { if (i != 0) { LocatedBlock prevBlock = blocks.get(i - 1); prevBlockIdStr = Long.toString(prevBlock.getBlock().getBlockId()); prevGenStamp = Long.toString(prevBlock.getBlock().getGenerationStamp()); prevStartOffset = prevBlock.getBlock().getNumBytes() - chunkSizeToView; if (prevStartOffset < 0) prevStartOffset = 0; prevBlockSize = prevBlock.getBlock().getNumBytes(); DatanodeInfo d = jspHelper.bestNode(prevBlock); String datanodeAddr = d.getName(); prevDatanodePort = Integer.parseInt( datanodeAddr.substring(datanodeAddr.indexOf(':') + 1, datanodeAddr.length())); prevHost = InetAddress.getByName(d.getHost()).getCanonicalHostName(); prevPort = d.getInfoPort(); } } } } else { // we are in the same block prevBlockIdStr = blockIdStr; prevStartOffset = startOffset - chunkSizeToView; if (prevStartOffset < 0) prevStartOffset = 0; prevBlockSize = blockSize; prevGenStamp = blockGenStamp; } String prevUrl = null; if (prevBlockIdStr != null) { prevUrl = "http://" + prevHost + ":" + prevPort + "/browseBlock.jsp?blockId=" + prevBlockIdStr + "&blockSize=" + prevBlockSize + "&startOffset=" + prevStartOffset + "&filename=" + URLEncoder.encode(filename, "UTF-8") + "&chunkSizeToView=" + chunkSizeToView + "&genstamp=" + prevGenStamp + "&datanodePort=" + prevDatanodePort + "&namenodeInfoPort=" + namenodeInfoPort + JspHelper.getDelegationTokenUrlParam(tokenString); out.print("<a href=\"" + prevUrl + "\">View Prev chunk</a> "); } out.print("<hr>"); out.print("<textarea cols=\"100\" rows=\"25\" wrap=\"virtual\" style=\"width:100%\" READONLY>"); try { jspHelper.streamBlockInAscii( new InetSocketAddress(req.getServerName(), datanodePort), blockId, accessToken, genStamp, blockSize, startOffset, chunkSizeToView, out, conf); } catch (Exception e) { out.print(e); } out.print("</textarea>"); dfs.close(); }