source: proiecte/HadoopJUnit/hadoop-0.20.1/src/webapps/datanode/tail.jsp @ 176

Last change on this file since 176 was 120, checked in by (none), 14 years ago

Added the mail files for the Hadoop JUNit Project
  • Property svn:executable set to *
File size: 4.1 KB
Line 
1<%@ page
2  contentType="text/html; charset=UTF-8"
3  import="javax.servlet.*"
4  import="javax.servlet.http.*"
5  import="java.io.*"
6  import="java.util.*"
7  import="java.net.*"
8  import="org.apache.hadoop.hdfs.*"
9  import="org.apache.hadoop.hdfs.server.namenode.*"
10  import="org.apache.hadoop.hdfs.server.datanode.*"
11  import="org.apache.hadoop.hdfs.protocol.*"
12  import="org.apache.hadoop.io.*"
13  import="org.apache.hadoop.conf.*"
14  import="org.apache.hadoop.net.DNS"
15  import="org.apache.hadoop.util.*"
16  import="org.apache.hadoop.net.NetUtils"
17  import="java.text.DateFormat"
18%>
19
20<%!
21  static JspHelper jspHelper = new JspHelper();
22
23  public void generateFileChunks(JspWriter out, HttpServletRequest req) 
24    throws IOException {
25    long startOffset = 0;
26   
27    int chunkSizeToView = 0;
28
29    String referrer = req.getParameter("referrer");
30    boolean noLink = false;
31    if (referrer == null) {
32      noLink = true;
33    }
34
35    String filename = req.getParameter("filename");
36    if (filename == null) {
37      out.print("Invalid input (file name absent)");
38      return;
39    }
40
41    String namenodeInfoPortStr = req.getParameter("namenodeInfoPort");
42    int namenodeInfoPort = -1;
43    if (namenodeInfoPortStr != null)
44      namenodeInfoPort = Integer.parseInt(namenodeInfoPortStr);
45   
46    String chunkSizeToViewStr = req.getParameter("chunkSizeToView");
47    if (chunkSizeToViewStr != null && Integer.parseInt(chunkSizeToViewStr) > 0)
48      chunkSizeToView = Integer.parseInt(chunkSizeToViewStr);
49    else chunkSizeToView = jspHelper.defaultChunkSizeToView;
50
51    if (!noLink) {
52      out.print("<h3>Tail of File: ");
53      JspHelper.printPathWithLinks(filename, out, namenodeInfoPort);
54            out.print("</h3><hr>");
55      out.print("<a href=\"" + referrer + "\">Go Back to File View</a><hr>");
56    }
57    else {
58      out.print("<h3>" + filename + "</h3>");
59    }
60    out.print("<b>Chunk size to view (in bytes, up to file's DFS block size): </b>");
61    out.print("<input type=\"text\" name=\"chunkSizeToView\" value=" +
62              chunkSizeToView + " size=10 maxlength=10>");
63    out.print("&nbsp;&nbsp;<input type=\"submit\" name=\"submit\" value=\"Refresh\"><hr>");
64    out.print("<input type=\"hidden\" name=\"filename\" value=\"" + filename +
65              "\">");
66    out.print("<input type=\"hidden\" name=\"namenodeInfoPort\" value=\"" + namenodeInfoPort +
67    "\">");
68    if (!noLink)
69      out.print("<input type=\"hidden\" name=\"referrer\" value=\"" + 
70                referrer+ "\">");
71
72    //fetch the block from the datanode that has the last block for this file
73    DFSClient dfs = new DFSClient(jspHelper.nameNodeAddr, 
74                                         jspHelper.conf);
75    List<LocatedBlock> blocks = 
76      dfs.namenode.getBlockLocations(filename, 0, Long.MAX_VALUE).getLocatedBlocks();
77    if (blocks == null || blocks.size() == 0) {
78      out.print("No datanodes contain blocks of file "+filename);
79      dfs.close();
80      return;
81    }
82    LocatedBlock lastBlk = blocks.get(blocks.size() - 1);
83    long blockSize = lastBlk.getBlock().getNumBytes();
84    long blockId = lastBlk.getBlock().getBlockId();
85    long genStamp = lastBlk.getBlock().getGenerationStamp();
86    DatanodeInfo chosenNode;
87    try {
88      chosenNode = jspHelper.bestNode(lastBlk);
89    } catch (IOException e) {
90      out.print(e.toString());
91      dfs.close();
92      return;
93    }     
94    InetSocketAddress addr = NetUtils.createSocketAddr(chosenNode.getName());
95    //view the last chunkSizeToView bytes while Tailing
96    if (blockSize >= chunkSizeToView)
97      startOffset = blockSize - chunkSizeToView;
98    else startOffset = 0;
99
100    out.print("<textarea cols=\"100\" rows=\"25\" wrap=\"virtual\" style=\"width:100%\" READONLY>");
101    jspHelper.streamBlockInAscii(addr, blockId, genStamp, blockSize, startOffset, chunkSizeToView, out);
102    out.print("</textarea>");
103    dfs.close();
104  }
105
106%>
107
108
109
110<html>
111<head>
112<%JspHelper.createTitle(out, request, request.getParameter("filename")); %>
113</head>
114<body>
115<form action="/tail.jsp" method="GET">
116<% 
117   generateFileChunks(out,request);
118%>
119</form>
120<hr>
121
122<h2>Local logs</h2>
123<a href="/logs/">Log</a> directory
124
125<%
126out.println(ServletUtil.htmlFooter());
127%>
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