overriding built-in tasks (not targets)

Hi.

My IDE generates an Ant script with the run-deploy and run-undeploy targets. They internally use the standard <get> task, but they don't check the outcome and sometimes return false positive.

The build is customizable by editing the file build.xml that includes this generated project file. I want to replace <get> with a macro that additionally greps the http response body for the success message.

The main problem is: when the macro tries to call the real <get>, it either fails with a stack overflow or with the message: "antcall task calling its own parent target". I thought I could fix it with name spaces, but it was too complex for me. My current workaround is to re-import org.apache.tools.ant.taskdefs.Get with a different task name.

There are some other issues with overriding <get> with a macrodef: the generated script calls get either with or without a password, but a macro cannot pass unknown attributes to the wrapped tasks. On the other hand, <presetdef> can pass them, but it won't let me add the additional checker task.
Macro attributes with default values don't work for the the "password" property of <get>, because null and empty string treated differently. There's no way to avoid calling the property setter, if the property has a default value in the macro instance. My workaround is to have two <real-get> elements in the custom script: with and without the password.

This leads to another problem: to invoke one of the <real-get> tasks conditionally I have to use <antcall> and because of that I can't support the optional children elements of <get>.


	<?xml version="1.0" encoding="utf-8"?>
	<project default="build" >
	
		<taskdef name="real-get" classname="org.apache.tools.ant.taskdefs.Get" />
		
		<macrodef name="get">
			<attribute name="src"/>
			<attribute name="dest"/>
			<attribute name="username" default="NOT-SET" />
			<attribute name="password" default="NOT-SET" />
			<sequential>
				<condition property="mymacro.no.creds">
					<and>
						<equals arg1="@{username}" arg2="NOT-SET"/>
						<equals arg1="@{password}" arg2="NOT-SET"/>
					</and>
				</condition>
				<property name="mymacro.src" value="@{src}"/>
				<property name="mymacro.dest" value="@{dest}"/>
				<property name="mymacro.username" value="@{username}"/>
				<property name="mymacro.password" value="@{password}"/>
				<antcall target="-get-without-creds"/>
				<antcall target="-get-with-creds"/>
				<!--
				TODO: check download result and optionally fail
				-->
				<echo message="some additional check"/>
			</sequential>
		</macrodef>
	
		<target name="-get-without-creds" if="mymacro.no.creds">
			<real-get src="${mymacro.src}" dest="${mymacro.dest}" />
		</target>
	
		<target name="-get-with-creds" unless="mymacro.no.creds">
			<real-get src="${mymacro.src}" dest="${mymacro.dest}" username="${mymacro.username}" password="${mymacro.password}" />
		</target>
		
		<target name="build">
			<get src="http://www.calife.com/HTML/test.php" dest="out.html"/>
		</target>
	
	</project>