Ant 1.8 include or import with nested resource collection - ant

I'd like to have Ant automatically include or import resources matching a particular pattern, but I'm really struggling with the syntax. Here's what I've tried:
<import>
<fileset dir="${basedir}" includes="*-graph.xml" />
</import>
However, I just get the error message
import requires file attribute or at least one nested resource
The documentation for import (and include) both say that you can use a nested resource collection, and the documentation for resource collections says <fileset> is a resource collection. I've Googled and can't find any useful examples at all.
I'm using Ant 1.8.1 (verified with ant -version)
EDIT
Found the problem. Firstly, SOMETHING has to match the expression. With no files that match, it blows up - even with optional=true, which is odd! Secondly, the matching files have be valid Ant file (even if they just contain <project/> - simply creating an empty file wasn't good enough).
Better error messages, please Apache! :-)

Try:
<foreach target="-import" param="file.name">
<fileset dir="${basedir}" includes="*-graph.xml" />
</foreach>
<target name="-import">
<import file="${file.name}" />
</target>
is in the ant-contrib tasks (http://ant-contrib.sourceforge.net/tasks/tasks/index.html) I'm not sure if this will work, I just came up with it on the fly.

Here is a simple way to deal with this problem:
<project name="the-name-of-the-project">
<import>
<fileset dir="${basedir}" includes="*-graph.xml" erroronmissingdir="false"/>
<fileset file="${ant.file.the-name-of-the-project}"/>
</import>
</project>
This way, the set of imported files is never empty since it includes the file containing this declaration. This works for <import> directives only, since it omits already imported files; <include> directives would trivially lead to a recursion.
Note the erroronmissingdir="false" is optional if basedir always exists.

Related

What are the usage restrictions on Ant's if/unless conditional attributes?

So we're using basic Ant 1.9.4, with a little use of 1.9.1's new if/unless attributes. For example,
<project xmlns:if="ant:if" xmlns:unless="ant:unless">
.... miles and miles of XML ....
<jar ....>
<service ....>
<provider classname="a.b.c.X" if:true="${some.flag}"/>
<provider ..../>
</service>
<fileset>
....the stuff in here will matter shortly....
</fileset>
</jar>
with some.flag always set to true or false, never left unset, and never set to any other value (assigned inside a property file read in earlier, if that matters), and it works wonderfully, giving us exactly the behavior we need. Joy!
More recently, we tried to make some of the jar task's fileset entries a little smarter, such as
<fileset dir="somedir">
<include name="optional_file" if:true="${some.flag}"/> <!-- same property name as before -->
</fileset>
With this syntax, we get an error "A zip file cannot include itself", with a line number pointing to the start of the jar task. This is obviously bogus syntax. However, changing this second if:true to simply if out of desperation -- and making no other changes -- avoids the error and gives us correct flag-based optional inclusion behavior.
What's going on here? Is the new syntax simply unavailable in <fileset> and/or fileset's nested <include> blocks?
As an experiment, I tried using an if:true or if:set attribute as appropriate in a few other useful places. Some places it worked perfectly. Some places I got some bizarre nonsense error, clearly the kind of thing that a parser prints when it's gone off the rails. Each time, reworking if:set="$(foo}" into if="foo" and if:true="${foo}" into if="${foo}" got back to the desired if-then behavior. So it's not a blocking problem, but we'd rather have the self-documenting :condition if we could.
I couldn't find mention of any such restriction in the Ant manual, but the manual describes the if/unless syntax in at least two different places using different descriptions. (I'm not sure where they are due to the manual's use of HTML frames; every URL shows up as index.html. Anytime I refer to the manual it feels like I'm browsing like it's 1999, baby! *does MC Hammer slide out of the room*)
Since Ant 1.4, <include> and <exclude> elements nested under <patternset> elements have supported if and else attributes. Each <fileset> has an implicit <patternset> nested under it, so the if and else attributes are available to it...
<condition property="some.flag.istrue">
<istrue value="${some.flag}"/>
</condition>
<fileset dir="somedir">
<!-- The "if" below is different than "if:true". -->
<include name="optional_file" if="some.flag.istrue"/>
</fileset>
In the above example, the if in <include> is an ordinary Ant attribute in the "default" Ant XML namespace. On the other hand, if:true is in the ant:if XML namespace.
The namespaced if:true doesn't work well with <include> elements. If the value provided to if:true doesn't evaluate to true, then Ant behaves as if the entire <include> element never existed. This is bad because Ant takes empty patternsets to mean "match every file". This is likely why you received the "A zip file cannot include itself" error; the <fileset> was likely containing the destination JAR file.
Stick with the plain if and else attributes for <include> and <exclude> elements and things should work.

Ant exclude file based on it's content

Is there any way to exclude files from an ant fileset based on the file content?
We do have test servers where code files are mixed up with files that have been generated by a CMS.
Usually, the files are placed in different folders, but there is a risk that real code files are in the middle of generated code.
The only way to differentiate generated files is to open the files and look at it's content. If the file contains a keyword, it should be excluded.
Does anyone know a way to perform this with Ant?
From the answer provided by Preet Sangha, Ishould use a filterchain. However, I'm missing a step here.
Let's say I load a text file of exclusions to be performed:
<loadfile property="exclusions" srcFile="exclusions.txt" />
But I don't know how to integrate it into my current copy task:
<copy todir="${test.dir}">
<fileset dir="${src.dir}">
</fileset>
</copy>
I tried to add the following exclude to the fileset but it does not do anything:
<exclude name="${exclusions}"/>
I'm sure I'm missing a simple step...
Have a look at the not and contains selectors.
The not selector contains an example of pretty much exactly what you're trying to do.
<copy todir="${test.dir}">
<fileset dir="${src.dir}">
<not>
<contains text="your-keyword-here"/>
</not>
</fileset>
</copy>
There's also the containsregexp selector which might be useful if your criteria for exclusion is more complicated.
There's a load more selectors you can use to refine your selection if needed.
I don't know ant but reading the docs....
Can you build a files list using a filterchain, and put this into the excludefiles of a fileset?
or
perhaps create a fileset with a filterchain that uses a filterreader and linecontainsregexp

Passing optional path arguments to ant

I have an ant task that uses an apply task to run a script on a group of files.
I have a directory structure resultant of something like this:
mkdir -p a/{b,c,d,e}/f
Normally (if I pass no arguments), I would like ant to run on all fs.
That is, if I called ant mytask, it should process: a/b/f, a/c/f, a/d/f, a/e/f. This already works using apply and patternsets.
However, when I pass it an optional argument called foo, it should only call the script on a/foo/f.
So if I called ant mytask -foo b, it should process a/b/f only, and not the others.
I have read this SO post, which explains ways of passing arguments, and I have looked at the ant documentation regarding properties, and conditionals. But I am still unable to piece them together in a way that works.
Also, I do not want to use one of the suggestions from the SO above which called for arguments like this:
<arg value="${arg0}"/>
<arg value="${arg1}"/>
I want to be able to call it as ant mytask -foo valueoffoo for any arbitrary foo.
Thanks.
I tried martin clayton's suggestion below and have code like:
<target name="mytask">
<property name="foo" value="*" />
<apply executable="perl">
<arg value="somescript"/>
<dirset id="them" dir="a">
<include name="${foo}/*/f" />
</dirset>
</apply>
</target>
The above does what I want.
Note 1: In my actual code I use a patternset instead of dirset but it should work the same.
Note 2: In my original question I said the directory structure was a/{b,c,d,e}/f. It is in fact a bit more complicated, hence the * in the include above. I omitted that the first time around because it did not seem relevant.
You can do this - albeit with a slightly different command-line syntax -
using a property 'override'.
First, in the buildfile, construct your fileset or dirset from a property foo,
something like this:
<property name="foo" value="*" />
<dirset id="them" dir="a">
<include name="${foo}/f" />
</dirset>
This will give you your default behaviour - processing all
subdirectories of a that themselves have a subdirectory f.
Now, if you run Ant like this:
ant -Dfoo=d
Only directory a/d/f will be processed.
This works because Ant properties are not mutable - well, not normally anyway -
so the command-line definition of foo prevents the one within the buildfile from being used.

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.

Filter a fileset referenced using a refid

I have a fileset (which is returned from the Maven Ant task), and it contains all the jars I need to repack. This fileset is referenced by a refid. I only want to include our own jars, so I would like to filter that. But Ant filesets don't support any further attributes or nested tags if a refid is used.
For example, if the fileset is:
org.foo.1.jar
org.foo.2.jar
log4j.jar
and I want to have a fileset which contains only
org.foo*.jar
How would I do that?
Try using a restrict resource collection, which you can use like a fileset in any task that uses resource collections to select the groups of files to operate on.
For example, for a fileset returned from your Maven task referenced via an id called dependency.fileset you can declare a restrict resource collection like so:
<restrict id="filtered.dependencies">
<fileset refid="dependency.fileset"/>
<rsel:name name="org.foo*.jar"/>
</restrict>
Note you'll have to declare the resource selector namespace as it isn't part of the built-in Ant namespace:
<project xmlns:rsel="antlib:org.apache.tools.ant.types.resources.selectors">
...
</project>
From here you can reference your restrict resource collection in a similar fashion to how you would reference your fileset. For example, to create backups of your filtered set of files:
<copy todir=".">
<restrict refid="filtered.dependencies"/>
<globmapper from="*" to="*.bak"/>
</copy>
Of course you can inline your restrict resource collection if you so desire:
<copy todir=".">
<restrict>
<fileset refid="dependency.fileset"/>
<rsel:name name="org.foo*.jar"/>
</restrict>
<globmapper from="*" to="*.bak"/>
</copy>
Have a look at the Ant documentation on resource collections for further information.
I think you'll need to write an ant task for that. They're pretty easy to write though.
See http://ant.apache.org/manual/develop.html#writingowntask
In your task, you'll need to call getProject() and ask it to give you the fileset, walk through it, and create a new one.
I 'm using Ant with Ivy. With the help of Ivy it is possible to filter dependencies for retrieval, with the following code in ivy.xml:
<dependency name="Project1" rev="latest.integration" transitive="true" conf="modlibs">
<exclude name="${exclusionRegEx}" matcher="regexp" />
</dependency>
<dependency name="Project2" rev="latest.integration" transitive="false" conf="modules"/>
Maybe a quick look at the Ivy source 'll help?
If you are using a sufficiently recent version of Ant and the JDK, for example, Ant 1.7 and JDK 6, then you can use the optional script task to do what you want. (Earlier versions may also work.) The page I linked to, if you scroll down to the text "The goal is to list the filesizes" then you'll see a sample script that creates a Fileset.
This isn't for the faint of heart, and a custom ant task you write yourself will probably be more flexible. But I wanted to point out the option.

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