Access Antlib Resources From Within Apache Ant Macros - ant

Is it possible to access resources from within Apache Ant macros defined in an Antlib?
For instance, within my antlib.xml, I have a macro that performs some XSLT. Ideally I would like the XSLT file to be packaged in the same JAR as the antlib.xml, but I have no idea how to specify the location of the XSLT.
Here is the (simplified) code:
<antlib xmlns:tibant="antlib:org.windyroad.tibant">
<macrodef name="configure-ear">
<attribute name="xml" />
<attribute name="out" />
<sequential>
<xslt in="#{xml}"
out="#{out}"
style="...what to put here...">
</xslt>
</sequential>
</macrodef>
</antlib>
The problem is that whatever I put in the style attribute is relative to the basedir for the project using the antlib and I can't find any way to specify a path relative to the antlib.xml.
Any ideas?
I can ship the XSLT as a separate file, but then I would need to give users some way to specify the location of the XSLT, which is not ideal (e.g. setting a tibant.home property). I could also use echoxml to write out the XSLT to a temp file, but IMO that's a hack.

Instead of using the style attribute, try a nested <style> element, which will allow you to specify a javaresource as the style sheet. You can then put the stylesheet next to your antlib.xml in the jar, and it will be available on the classpath.
<xslt in="#{xml}"
out="#{out}">
<style>
<javaresource name="your/package/structure/style.xslt" />
</style>
</xslt>

The first thing I would look at is to load XSL from the classloader as a resource. You should be able to accomplish this with LoadResource task (http://ant.apache.org/manual/Tasks/loadresource.html). The next I would look at options that XSLT task gives you for the specifying style. It doesn't look like it has any ability to take literal contents of XSLT. You can work around this by writing out the XSLT content to a temporary file and then giving the path to the temp file to the XSLT task.
So...
Load XSLT text from the classloader.
Acquire a temporary file using Tempfile task (http://ant.apache.org/manual/Tasks/tempfile.html).
Write out XSLT text to the temp file using Echo task.
Invoke XSLT with reference to the temp file.

Related

concat as resource collection in zip not working?

I'm trying to use <concat> as a resource collection in a <zip> task and, according to the documentation, this should work. I'd like to do this because some of the files I want to include in the zip need to have some properties expanded, so I will also add a <filterchain> to the <concat> to do this. I'd prefer to do it directly rather than copying to a temp location (with property substitution) and including the copy in the zip file.
However, I can't seem to get <zip> to correctly use the <concat> element.
A simplified example of what I have so far:
<zip destfile="target/dist.zip">
<concat>
<fileset file="CHANGES.txt" />
</concat>
</zip>
This creates a zip file containing several directories all named concat (C: (obviously this is on a Windows machine).
What am I missing?
A colleague and I came up with the answer by looking through the <zip> and <concat> source. There are really two answers:
<concat>'s implementation of the ResourceCollection interface is odd, but we understand why.
There's a way around that.
For #1, while <concat> is a ResourceCollection (like FileSet), under the hood it returns as the name of single Resource it contains a hard-coded value:
"concat (" + String.valueOf(c) + ")";
Look familiar?
The name of resources is normally ignored--except by <zip> and its related tasks, which uses the resource name as the ZipEntry name. Since <concat> returns the odd-looking name, that's what we get in the zip file.
I haven't quite figured out why I get multiple entries, but it doesn't matter: the observation leads to a convoluted solution.
Since I know the name of the ZipEntry I want to create, I can use a <mapper> to give the <concat> resource a name. Here's what I came up with in all its glory:
<zip destfile="target/distribution.zip">
<fileset dir=".">
<exclude name="target/**" />
<exclude name="CHANGES.txt" />
</fileset>
<mappedresources>
<concat>
<fileset file="CHANGES.txt" />
<filterchain>
<expandproperties />
</filterchain>
</concat>
<mergemapper to="CHANGES.txt" />
</mappedresources>
</zip>
As my colleague says "In Ant every problem can be solved using a mapper."
This only works for Ant 1.8+ because <mappedresources> was added in that release.
I'm going to post some comments to the Ant mailing list and suggest a couple of enhancements:
Allow a resource name to be specified as an attribute on <concat> when it's being used as a ResourceCollection.
Throw an exception (and don't create a synthetic value) if getName() is called without having a value specified.
Finally, though not directly related, I do wish <expandproperties> could take a <propertyset> so I can control which properties get substituted.
Do you want the final zip to contain a single file or multiple files? As far as I can see, using concat (when done successfully, which isn't done above) would produce a single file, the result of concatenation of all files in the resource collection.
If you want multiple files rather than concatenation, I think intermediate copy is what you'll need.
From Ant manual for the concat task:
Since Apache Ant 1.7.1, this task can
be used as a Resource Collection that
will return exactly one resource.

How do I make a fileset from a comma-separated list of directories in Ant?

In an Ant target I get a property, containing the list of directories to be included in further action (copying, filtering, etc.). It looks like this:
directories=dir1, dir2, dir3
I need a way to convert this list to a fileset or patternset that selects all the files in these directories.
I know I can use a script to generate pattern strings and then use it in the "include" or "exclude", but is there are a way to avoid scripts?
Note that as of Ant 1.9.4, there is a new construct <multirootfileset> that provides that functionality, even if the dirs are not siblings:
<multirootfileset basedirs="${directories}" includes="**/*">
How about using the antcontrib propertyregex task to convert the comma-separated list into wildcards suitable for a fileset?
<property name="directories" value="dir1, dir2, dir3" />
<property name="wildcard" value="${file.separator}**${file.separator}*" />
<propertyregex property="my_pattern"
input="${directories}"
regexp=", "
replace="${wildcard}," />
At this point we now have:
my_pattern=dir1/**/*,dir2/**/*,dir3
That can be used with a further suffixed wildcard to get the full fileset:
<fileset dir="." id="my_fileset" includes="${my_pattern}${wildcard}" />
(The fiddly ${wildcard} is to ensure portability between unix and windows filesystems, you could use /**/* if you're pure unix.)
Something like this should work:
<dirset includes="${directories}"/>
Yes, dirset isn't fileset. However, it may be enough, or else you can probably use a for or foreach from ant-contrib to iterate over the directories in your target. You might also be able to define a ResourceCollection based around the dirset. It might help to know what the "further action" is expected to be.
However, this feels like too much work ...

How to replace template in one file with content of another file?

I have a file username.txt with one word in it.
I have another file with template in it:
<root>
<user name="${username}">
</root>
I need during ant build change template ${username} with content of file username.txt.
How to do it?
What ant task should I use for this purpose?
If you can make your first file be a properties file instead of containing just the one word e.g.
username=superuser
Then you can load it using the property task. e.g.
<property file="username.properties" />
Update
If the file format needs to remain as in the question then take a look at the LoadFile task. It can be used to load the contents of a file into a property. e.g.
<loadfile property="username" srcFile="username.txt" />

How can I iterate over properties from a file?

All my projects and their versions are defined in a properties file like this:
ProjectNameA=0.0.1
ProjectNameB=1.4.2
I'd like to iterate over all the projects, and use their names and versions in an Ant script.
At present I read the entire file using the property task, then iterate over a given list in a for loop like this:
<for list="ProjectNameA,ProjectNameB" param="project">
<sequential>
<echo message="#{project} has version ${#{project}}" />
</sequential>
</for>
How can I avoid the hard-coding of the project names in the for loop?
Basically iterate over each line and extract the name and the version of a project as I go.
Seeing as you're already using antcontrib for, how about making use of the propertyselector task:
<property file="properties.txt" prefix="projects."/>
<propertyselector property="projects" match="projects\.(.*)" select="\1"/>
<property file="properties.txt" />
<for list="${projects}" param="project">
...
</for>
The idea here is to read the properties once with the projects prefix, and use the resulting set of properties to build a comma-separated list of projects with the propertyselector task. Then the properties are re-read without the prefix, so that your for loop can proceed as before.
Something you want to keep in mind, if you are reading additional .property files (besides build.properties) is scoping. If you read an additional file (via the property file="foo.property") tag, ant will show that the file was read, and the properties loaded. However, when you goto reference them, they come up un-defined.

ANT: How to call target for all build.xml in subdirectories?

How do you call a specific target in all build.xml located in all subdirectories using wildcards (ie not hard coding the subdirectory names)? The below answer is hardcoded. Is there a way to do it without hardcode?
Similar to this question: Pass ant target to multiple build.xml files in subdirectories
Use the Ant subant task like this:
<subant target="sometarget">
<fileset dir="." includes="*/build.xml" />
</subant>
If you include an "inheritall" attribute (same as how it's used in but defaults the opposite), you can share all your current project's properties and everything too. This also makes it very easy to overwrite tasks defined in your main build.xml file if you need to.
Read more about it here.
I'll setup different properties within my build.properties file. I use these to dynamically build paths in my targets.
Define the location of your build.properties file:
<!-- all properties are in build.properties -->
<property file="build.properties" />
Use those properties in your targets:
Properties in the build properties are similar to setting up an .ini file:
project.rootdir=c:/Deploy
project.tempbuilddir = c:/Deploy/Temp/Inetpub
project.builddir=c:/Deploy/Inetpub
# Build prefix will be added to that tags urls (.../tags/${project.buildprefix}Build_${today.date})
project.buildprefix=ACA_
I guess you could use a dynamic file as your properties file, if necessary, as long as you define the proper path to the file. You could point it to a server-side file to dynamically write your properties file (ColdFusion, PHP, JSP, whatever).
I've used ant-contrib's foreach task to do something like this.
http://ant-contrib.sourceforge.net/tasks/tasks/foreach.html
Sounds like a perfect candidate for the <subant> task.

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