Perl reading zip files with IO::Uncompress::AnyUncompress - perl

Question

We are moving from our current build system (which is a mess) to one that uses Ant with Ivy. I'm cleaning up all the build files, and finding the jar dependencies. I thought it might be easier if I could automate it a bit, by going through the jars that are checked into the project, finding what classes they contain, then matching those classes with the various import statements in the Java code.
I have used Archive::Tar before, but Archive::Zip isn't a standard Perl module. (My concern is that someone is going to try my script, call me in the middle of the night and tell me it isn't working.)
I noticed that IO::Uncompress::AnyUncompress is a standard module, so I thought I could try IO::Uncompress::AnyUncompressor at leastIO::Uncompress::Unzip` which is also a standard module.
Unfortunately, the documentation for these modules give no examples (According to the documentation, examples are a todo).
I'm able to successfully open my jar and create an object:
my $zip_obj = IO::Uncompress::AnyUncompress->new ( $zip_file );
Now, I want to see the contents. According to the documentation:
getHeaderInfo
Usage is
$hdr = $z->getHeaderInfo();
#hdrs = $z->getHeaderInfo();
This method returns either a hash reference (in scalar context) or a list or hash references (in array context) that contains information about each of the header fields in the compressed data stream(s).
Okay, this isn't an object like Archive::Tar or Archive::Zip returns, and there are no methods or subroutines mentioned to parse the data. I'll use Data::Dumper and see what hash keys are contained in the reference.
Here's a simple test program:
#! /usr/bin/env perl
use 5.12.0;
use warnings;
use IO::Uncompress::AnyUncompress;
use Data::Dumper;
my $obj = IO::Uncompress::AnyUncompress->new("testng.jar")
or die qq(You're an utter failure);
say qq(Dump of \$obj = ) . Dumper $obj;
my #header2 = $obj->getHeaderInfo;
say qq(Dump of \$header = ) . Dumper $headers->[0];
And here's my results:
Dump of $obj = $VAR1 = bless( \*Symbol::GEN0, 'IO::Uncompress::Unzip' );
Dump of $header = $VAR1 = {
'UncompressedLength' => 0,
'Zip64' => 0,
'MethodName' => 'Stored',
'Stream' => 0,
'Time' => 1181224440,
'MethodID' => 0,
'CRC32' => 0,
'HeaderLength' => 43,
'ExtraFieldRaw' => '¦- ',
'ExtraField' => [
[
'¦-',
''
]
],
'FingerprintLength' => 4,
'Type' => 'zip',
'TrailerLength' => 0,
'CompressedLength' => 0,
'Name' => 'META-INF/',
'Header' => 'PK
+N¦6 META-INF/¦- '
};
Some of that looks sort of useful. However, all of my entries return `'Name' => 'META-INF/``, so it doesn't look like a file name.
Is it possible to use IO::Uncompress::AnyUncompress (or even IO::Uncompress:Unzip) to read through the archive and see what files are in its contents. And, if so, how do I parse that header?
Otherwise, I'll have to go with Archive::Zip and let people know they have to download and install it from CPAN on their systems.

Answer 1

The files in the archive are compressed in different data streams, so you need to iterate through the streams to get the individual files.
use strict;
use warnings;
use IO::Uncompress::Unzip qw(unzip $UnzipError);
my $zipfile = 'zipfile.zip';
my $u = new IO::Uncompress::Unzip $zipfile
or die "Cannot open $zipfile: $UnzipError";
die "Zipfile has no members"
if ! defined $u->getHeaderInfo;
for (my $status = 1; $status > 0; $status = $u->nextStream) {
my $name = $u->getHeaderInfo->{Name};
warn "Processing member $name\n" ;
if ($name =~ /\/$/) {
mkdir $name;
}
else {
unzip $zipfile => $name, Name => $name
or die "unzip failed: $UnzipError\n";
}
}