<%@ page
contentType="text/html; charset=UTF-8"
import="javax.servlet.*"
import="javax.servlet.http.*"
import="java.io.*"
import="java.util.*"
import="java.net.*"
import="org.apache.hadoop.hdfs.*"
import="org.apache.hadoop.hdfs.server.namenode.*"
import="org.apache.hadoop.hdfs.server.datanode.*"
import="org.apache.hadoop.hdfs.protocol.*"
import="org.apache.hadoop.io.*"
import="org.apache.hadoop.conf.*"
import="org.apache.hadoop.net.DNS"
import="org.apache.hadoop.util.*"
import="org.apache.hadoop.net.NetUtils"
import="java.text.DateFormat"
%>
<%!
static JspHelper jspHelper = new JspHelper();
public void generateFileChunks(JspWriter out, HttpServletRequest req)
throws IOException {
long startOffset = 0;
int chunkSizeToView = 0;
String referrer = req.getParameter("referrer");
boolean noLink = false;
if (referrer == null) {
noLink = true;
}
String filename = req.getParameter("filename");
if (filename == null) {
out.print("Invalid input (file name absent)");
return;
}
String namenodeInfoPortStr = req.getParameter("namenodeInfoPort");
int namenodeInfoPort = -1;
if (namenodeInfoPortStr != null)
namenodeInfoPort = Integer.parseInt(namenodeInfoPortStr);
String chunkSizeToViewStr = req.getParameter("chunkSizeToView");
if (chunkSizeToViewStr != null && Integer.parseInt(chunkSizeToViewStr) > 0)
chunkSizeToView = Integer.parseInt(chunkSizeToViewStr);
else chunkSizeToView = jspHelper.defaultChunkSizeToView;
if (!noLink) {
out.print("Tail of File: ");
JspHelper.printPathWithLinks(filename, out, namenodeInfoPort);
out.print("
");
out.print("Go Back to File View
");
}
else {
out.print("" + filename + "
");
}
out.print("Chunk size to view (in bytes, up to file's DFS block size): ");
out.print("");
out.print("
");
out.print("");
out.print("");
if (!noLink)
out.print("");
//fetch the block from the datanode that has the last block for this file
DFSClient dfs = new DFSClient(jspHelper.nameNodeAddr,
jspHelper.conf);
List blocks =
dfs.namenode.getBlockLocations(filename, 0, Long.MAX_VALUE).getLocatedBlocks();
if (blocks == null || blocks.size() == 0) {
out.print("No datanodes contain blocks of file "+filename);
dfs.close();
return;
}
LocatedBlock lastBlk = blocks.get(blocks.size() - 1);
long blockSize = lastBlk.getBlock().getNumBytes();
long blockId = lastBlk.getBlock().getBlockId();
long genStamp = lastBlk.getBlock().getGenerationStamp();
DatanodeInfo chosenNode;
try {
chosenNode = jspHelper.bestNode(lastBlk);
} catch (IOException e) {
out.print(e.toString());
dfs.close();
return;
}
InetSocketAddress addr = NetUtils.createSocketAddr(chosenNode.getName());
//view the last chunkSizeToView bytes while Tailing
if (blockSize >= chunkSizeToView)
startOffset = blockSize - chunkSizeToView;
else startOffset = 0;
out.print("");
dfs.close();
}
%>
<%JspHelper.createTitle(out, request, request.getParameter("filename")); %>
Local logs
Log directory
<%
out.println(ServletUtil.htmlFooter());
%>