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<link rel="stylesheet" type="text/css" href="../stylesheets/style.css">
<title>Get Task</title>
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<h2><a name="get">Get</a></h2>
<h3>Description</h3>
<p>Gets a file from a URL. When the verbose option is &quot;on&quot;, this task
displays a '.' for every 100 Kb retrieved. Any URL schema supported by
the runtime is valid here, including http:, ftp: and jar:; 
https: is only valid if the appropriate support is added to the pre-1.4 Java
runtimes. 
 
</p>
The <i>usetimestamp</i> option enables you to control downloads so that the remote file is
only fetched if newer than the local copy. If there is no local copy, the download always takes 
place. When a file is downloaded, the timestamp of the downloaded file is set to the remote timestamp,
if  the JVM is Java1.2 or later. 
NB: This timestamp facility only works on downloads using the HTTP protocol. 
<p>
A username and password can be specified, in which case basic 'slightly encoded
plain text' authentication is used. This is only secure over an HTTPS link.
</p>
<p>
<b>Proxies</b>. Since Ant1.7, Ant running on Java1.5 or later defaults to 
    <a href="../proxy.html">using
    the proxy settings of the operating system</a>. There is also the  
 <a href="../OptionalTasks/setproxy.html">&lt;setproxy&gt;</a> task for
    earlier Java versions. With proxies turned on, <code>&lt;get&gt;</code> requests against
    localhost may not work as expected, if the request is relayed to the proxy.
    The <code>-noproxy</code> option can be used to turn this feature off.
</p>
 
<h3>Parameters</h3>
<table border="1" cellpadding="2" cellspacing="0">
  <tr>
    <td valign="top"><b>Attribute</b></td>
    <td valign="top"><b>Description</b></td>
    <td align="center" valign="top"><b>Required</b></td>
  </tr>
  <tr>
    <td valign="top">src</td>
    <td valign="top">the URL from which to retrieve a file.</td>
    <td align="center" valign="top">Yes</td>
  </tr>
  <tr>
    <td valign="top">dest</td>
    <td valign="top">the file where to store the retrieved file.</td>
    <td align="center" valign="top">Yes</td>
  </tr>
  <tr>
    <td valign="top">verbose</td>
    <td valign="top">show verbose progress information (&quot;on&quot;/&quot;off&quot;).</td>
    <td align="center" valign="top">No; default "false"</td>
  </tr>
  <tr>
    <td valign="top">ignoreerrors</td>
    <td valign="top">Log errors but don't treat as fatal.</td>
    <td align="center" valign="top">No; default "false"</td>
  </tr>
  <tr>
    <td valign="top">usetimestamp</td>
    <td valign="top">conditionally download a file based on the timestamp of the
    local copy. HTTP only</td>
    <td align="center" valign="top">No; default "false"</td>
  </tr>
  <tr>
    <td valign="top">username</td>
    <td valign="top">username for 'BASIC' http authentication</td>
    <td align="center" valign="top">if password is set</td>
  </tr>  
  <tr>
    <td valign="top">password</td>
    <td valign="top">password: required </td>
    <td align="center" valign="top">if username is set</td>
  </tr>  
  <tr>
    <td valign="top">maxtime</td>
    <td valign="top">Maximum time in seconds the download may take,
    otherwise it will be interrupted and treated like a download
      error.  <em>Since Ant 1.8.0</em></td>
    <td align="center" valign="top">No: default 0 which means no
      maximum time</td>
  </tr>  
  <tr>
    <td valign="top">retries</td>
    <td valign="top">the number of retries on error<br/>
      <em>since Ant 1.8.0</em></td>
    <td align="center" valign="top">No; default "3"</td>
  </tr>
  <tr>
    <td valign="top">skipexisting</td>
    <td valign="top">skip files that already exist on the local filesystem<br/>
      <em>since Ant 1.8.0</em></td>
    <td align="center" valign="top">No; default "false"</td>
  </tr>
   <tr>
    <td valign="top">httpusecaches</td>
    <td valign="top">HTTP only - if true, allow caching at the
      HttpUrlConnection level.  if false, turn caching off.<br/>
      <b>Note</b> this is only a hint to the underlying UrlConnection
      class, implementations and proxies are free to ignore the
      setting.</td>
    <td align="center" valign="top">No; default "true"</td>
  </tr>
</table>
<h3>Examples</h3>
<pre>  &lt;get src=&quot;http://ant.apache.org/&quot; dest=&quot;help/index.html&quot;/&gt;</pre>
<p>Gets the index page of http://ant.apache.org/, and stores it in the file <code>help/index.html</code>.</p>

<pre>  &lt;get src=&quot;http://www.apache.org/dist/ant/KEYS&quot; 
    dest=&quot;KEYS&quot; 
    verbose=&quot;true&quot;
    usetimestamp=&quot;true&quot;/&gt;</pre>
<p>
Gets the PGP keys of Ant's (current and past) release managers, if the local copy
is missing or out of date. Uses the verbose option 
for progress information.
</p>

<pre>  &lt;get src=&quot;https://insecure-bank.org/statement/user=1214&quot; 
    dest=&quot;statement.html&quot; 
    username="1214";
    password="secret"/&gt;</pre>
<p>
Fetches some file from a server with access control. Because https is being used the
fact that basic auth sends passwords in plaintext is moot if you
ignore the fact that it is part of your build file which may be
readable by third parties.  If you need more security, consider using
the <a href="input.html">input task</a> to query for a password.</p>

<p>Using a macro like the following</p>

<pre>
  &lt;macrodef name="get-and-checksum">
    &lt;attribute name="url"/>
    &lt;attribute name="dest"/>
    &lt;sequential>
      &lt;get src="@{url}" dest="@{dest}"/>
      &lt;get src="@{url}.sha1" dest="@{dest}.sha"/>
      &lt;local name="checksum.matches"/>
      &lt;local name="checksum.matches.fail"/>
      &lt;checksum file="@{dest}" algorithm="sha" fileext=".sha"
                verifyproperty="checksum.matches"/>
      &lt;condition property="checksum.matches.fail">
        &lt;equals arg1="${checksum.matches}" arg2="false"/>
      &lt;/condition>
      &lt;fail if="checksum.matches.fail">Checksum error&lt;/fail>
    &lt;/sequential>
  &lt;/macrodef>
</pre>

<p>it is possible to download an artifacts together with its SHA1
  checksum (assuming a certain naming convention for the checksum
  file, of course) and validate the checksum on the fly.</p>

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