Acme-Throw
view release on metacpan or search on metacpan
t/lib/Capture/Tiny.pm view on Meta::CPAN
}
#--------------------------------------------------------------------------#
# create API subroutines and export them
# [do STDOUT flag, do STDERR flag, do merge flag, do tee flag]
#--------------------------------------------------------------------------#
my %api = (
capture => [1,1,0,0],
capture_stdout => [1,0,0,0],
capture_stderr => [0,1,0,0],
capture_merged => [1,1,1,0],
tee => [1,1,0,1],
tee_stdout => [1,0,0,1],
tee_stderr => [0,1,0,1],
tee_merged => [1,1,1,1],
);
for my $sub ( keys %api ) {
my $args = join q{, }, @{$api{$sub}};
eval "sub $sub(&;@) {unshift \@_, $args; goto \\&_capture_tee;}"; ## no critic
}
our @ISA = qw/Exporter/;
our @EXPORT_OK = keys %api;
t/lib/Capture/Tiny.pm view on Meta::CPAN
}
else {
_open \*STDOUT, ">" . File::Spec->devnull;
# _debug( "# proxied STDOUT as " . (defined fileno STDOUT ? fileno STDOUT : 'undef' ) . "\n" );
_open $dup{stdout} = IO::Handle->new, ">&=STDOUT";
}
$proxies{stdout} = \*STDOUT;
binmode(STDOUT, ':utf8') if $] >= 5.008; ## no critic
}
if ( ! defined fileno STDERR ) {
$proxy_count{stderr}++;
if (defined $dup{stderr}) {
_open \*STDERR, ">&=" . fileno($dup{stderr});
# _debug( "# restored proxy STDERR as " . (defined fileno STDERR ? fileno STDERR : 'undef' ) . "\n" );
}
else {
_open \*STDERR, ">" . File::Spec->devnull;
# _debug( "# proxied STDERR as " . (defined fileno STDERR ? fileno STDERR : 'undef' ) . "\n" );
_open $dup{stderr} = IO::Handle->new, ">&=STDERR";
}
$proxies{stderr} = \*STDERR;
binmode(STDERR, ':utf8') if $] >= 5.008; ## no critic
}
return %proxies;
}
sub _unproxy {
my (%proxies) = @_;
# _debug( "# unproxying: " . join(" ", keys %proxies) . "\n" );
for my $p ( keys %proxies ) {
$proxy_count{$p}--;
t/lib/Capture/Tiny.pm view on Meta::CPAN
if ( ! $proxy_count{$p} ) {
_close $proxies{$p};
_close $dup{$p} unless $] < 5.008; # 5.6 will have already closed this as dup
delete $dup{$p};
}
}
}
sub _copy_std {
my %handles;
for my $h ( qw/stdout stderr stdin/ ) {
next if $h eq 'stdin' && ! $IS_WIN32; # WIN32 hangs on tee without STDIN copied
my $redir = $h eq 'stdin' ? "<&" : ">&";
_open $handles{$h} = IO::Handle->new(), $redir . uc($h); # ">&STDOUT" or "<&STDIN"
}
return \%handles;
}
# In some cases we open all (prior to forking) and in others we only open
# the output handles (setting up redirection)
sub _open_std {
my ($handles) = @_;
_open \*STDIN, "<&" . fileno $handles->{stdin} if defined $handles->{stdin};
_open \*STDOUT, ">&" . fileno $handles->{stdout} if defined $handles->{stdout};
_open \*STDERR, ">&" . fileno $handles->{stderr} if defined $handles->{stderr};
}
#--------------------------------------------------------------------------#
# private subs
#--------------------------------------------------------------------------#
sub _start_tee {
my ($which, $stash) = @_; # $which is "stdout" or "stderr"
# setup pipes
$stash->{$_}{$which} = IO::Handle->new for qw/tee reader/;
pipe $stash->{reader}{$which}, $stash->{tee}{$which};
# _debug( "# pipe for $which\: " . _name($stash->{tee}{$which}) . " " . fileno( $stash->{tee}{$which} ) . " => " . _name($stash->{reader}{$which}) . " " . fileno( $stash->{reader}{$which}) . "\n" );
select((select($stash->{tee}{$which}), $|=1)[0]); # autoflush
# setup desired redirection for parent and child
$stash->{new}{$which} = $stash->{tee}{$which};
$stash->{child}{$which} = {
stdin => $stash->{reader}{$which},
stdout => $stash->{old}{$which},
stderr => $stash->{capture}{$which},
};
# flag file is used to signal the child is ready
$stash->{flag_files}{$which} = scalar tmpnam();
# execute @cmd as a separate process
if ( $IS_WIN32 ) {
local $@;
eval "use Win32API::File qw/CloseHandle GetOsFHandle SetHandleInformation fileLastError HANDLE_FLAG_INHERIT INVALID_HANDLE_VALUE/ ";
# _debug( "# Win32API::File loaded\n") unless $@;
my $os_fhandle = GetOsFHandle( $stash->{tee}{$which} );
# _debug( "# Couldn't get OS handle: " . fileLastError() . "\n") if ! defined $os_fhandle || $os_fhandle == INVALID_HANDLE_VALUE();
t/lib/Capture/Tiny.pm view on Meta::CPAN
_open_std( $stash->{child}{$which} );
$stash->{pid}{$which} = system(1, @cmd, $stash->{flag_files}{$which});
# not restoring std here as it all gets redirected again shortly anyway
}
else { # use fork
_fork_exec( $which, $stash );
}
}
sub _fork_exec {
my ($which, $stash) = @_; # $which is "stdout" or "stderr"
my $pid = fork;
if ( not defined $pid ) {
Carp::confess "Couldn't fork(): $!";
}
elsif ($pid == 0) { # child
# _debug( "# in child process ...\n" );
untie *STDIN; untie *STDOUT; untie *STDERR;
_close $stash->{tee}{$which};
# _debug( "# redirecting handles in child ...\n" );
_open_std( $stash->{child}{$which} );
t/lib/Capture/Tiny.pm view on Meta::CPAN
my $text = do { local $/; scalar readline $fh };
return defined($text) ? $text : "";
}
#--------------------------------------------------------------------------#
# _capture_tee() -- generic main sub for capturing or teeing
#--------------------------------------------------------------------------#
sub _capture_tee {
# _debug( "# starting _capture_tee with (@_)...\n" );
my ($do_stdout, $do_stderr, $do_merge, $do_tee, $code, @opts) = @_;
my %do = ($do_stdout ? (stdout => 1) : (), $do_stderr ? (stderr => 1) : ());
Carp::confess("Custom capture options must be given as key/value pairs\n")
unless @opts % 2 == 0;
my $stash = { capture => { @opts } };
for ( keys %{$stash->{capture}} ) {
my $fh = $stash->{capture}{$_};
Carp::confess "Custom handle for $_ must be seekable\n"
unless ref($fh) eq 'GLOB' || (blessed($fh) && $fh->isa("IO::Seekable"));
}
# save existing filehandles and setup captures
local *CT_ORIG_STDIN = *STDIN ;
local *CT_ORIG_STDOUT = *STDOUT;
local *CT_ORIG_STDERR = *STDERR;
# find initial layers
my %layers = (
stdin => [PerlIO::get_layers(\*STDIN) ],
stdout => [PerlIO::get_layers(\*STDOUT, output => 1)],
stderr => [PerlIO::get_layers(\*STDERR, output => 1)],
);
# _debug( "# existing layers for $_\: @{$layers{$_}}\n" ) for qw/stdin stdout stderr/;
# get layers from underlying glob of tied filehandles if we can
# (this only works for things that work like Tie::StdHandle)
$layers{stdout} = [PerlIO::get_layers(tied *STDOUT)]
if tied(*STDOUT) && (reftype tied *STDOUT eq 'GLOB');
$layers{stderr} = [PerlIO::get_layers(tied *STDERR)]
if tied(*STDERR) && (reftype tied *STDERR eq 'GLOB');
# _debug( "# tied object corrected layers for $_\: @{$layers{$_}}\n" ) for qw/stdin stdout stderr/;
# bypass scalar filehandles and tied handles
# localize scalar STDIN to get a proxy to pick up FD0, then restore later to CT_ORIG_STDIN
my %localize;
$localize{stdin}++, local(*STDIN)
if grep { $_ eq 'scalar' } @{$layers{stdin}};
$localize{stdout}++, local(*STDOUT)
if $do_stdout && grep { $_ eq 'scalar' } @{$layers{stdout}};
$localize{stderr}++, local(*STDERR)
if ($do_stderr || $do_merge) && grep { $_ eq 'scalar' } @{$layers{stderr}};
$localize{stdin}++, local(*STDIN), _open( \*STDIN, "<&=0")
if tied *STDIN && $] >= 5.008;
$localize{stdout}++, local(*STDOUT), _open( \*STDOUT, ">&=1")
if $do_stdout && tied *STDOUT && $] >= 5.008;
$localize{stderr}++, local(*STDERR), _open( \*STDERR, ">&=2")
if ($do_stderr || $do_merge) && tied *STDERR && $] >= 5.008;
# _debug( "# localized $_\n" ) for keys %localize;
# proxy any closed/localized handles so we don't use fds 0, 1 or 2
my %proxy_std = _proxy_std();
# _debug( "# proxy std: @{ [%proxy_std] }\n" );
# update layers after any proxying
$layers{stdout} = [PerlIO::get_layers(\*STDOUT, output => 1)] if $proxy_std{stdout};
$layers{stderr} = [PerlIO::get_layers(\*STDERR, output => 1)] if $proxy_std{stderr};
# _debug( "# post-proxy layers for $_\: @{$layers{$_}}\n" ) for qw/stdin stdout stderr/;
# store old handles and setup handles for capture
$stash->{old} = _copy_std();
$stash->{new} = { %{$stash->{old}} }; # default to originals
for ( keys %do ) {
$stash->{new}{$_} = ($stash->{capture}{$_} ||= File::Temp->new);
seek( $stash->{capture}{$_}, 0, 2 ) or die "Could not seek on capture handle for $_\n";
$stash->{pos}{$_} = tell $stash->{capture}{$_};
# _debug("# will capture $_ on " . fileno($stash->{capture}{$_})."\n" );
_start_tee( $_ => $stash ) if $do_tee; # tees may change $stash->{new}
}
_wait_for_tees( $stash ) if $do_tee;
# finalize redirection
$stash->{new}{stderr} = $stash->{new}{stdout} if $do_merge;
# _debug( "# redirecting in parent ...\n" );
_open_std( $stash->{new} );
# execute user provided code
my ($exit_code, $inner_error, $outer_error, @result);
{
local *STDIN = *CT_ORIG_STDIN if $localize{stdin}; # get original, not proxy STDIN
# _debug( "# finalizing layers ...\n" );
_relayer(\*STDOUT, $layers{stdout}) if $do_stdout;
_relayer(\*STDERR, $layers{stderr}) if $do_stderr;
# _debug( "# running code $code ...\n" );
local $@;
eval { @result = $code->(); $inner_error = $@ };
$exit_code = $?; # save this for later
$outer_error = $@; # save this for later
}
# restore prior filehandles and shut down tees
# _debug( "# restoring filehandles ...\n" );
_open_std( $stash->{old} );
_close( $_ ) for values %{$stash->{old}}; # don't leak fds
# shouldn't need relayering originals, but see rt.perl.org #114404
_relayer(\*STDOUT, $layers{stdout}) if $do_stdout;
_relayer(\*STDERR, $layers{stderr}) if $do_stderr;
_unproxy( %proxy_std );
# _debug( "# killing tee subprocesses ...\n" ) if $do_tee;
_kill_tees( $stash ) if $do_tee;
# return captured output, but shortcut in void context
# unless we have to echo output to tied/scalar handles;
my %got;
if ( defined wantarray or ($do_tee && keys %localize) ) {
for ( keys %do ) {
_relayer($stash->{capture}{$_}, $layers{$_});
$got{$_} = _slurp($_, $stash);
# _debug("# slurped " . length($got{$_}) . " bytes from $_\n");
}
print CT_ORIG_STDOUT $got{stdout}
if $do_stdout && $do_tee && $localize{stdout};
print CT_ORIG_STDERR $got{stderr}
if $do_stderr && $do_tee && $localize{stderr};
}
$? = $exit_code;
$@ = $inner_error if $inner_error;
die $outer_error if $outer_error;
# _debug( "# ending _capture_tee with (@_)...\n" );
return unless defined wantarray;
my @return;
push @return, $got{stdout} if $do_stdout;
push @return, $got{stderr} if $do_stderr && ! $do_merge;
push @return, @result;
return wantarray ? @return : $return[0];
}
1;
__END__
=pod
t/lib/Capture/Tiny.pm view on Meta::CPAN
=head1 VERSION
version 0.23
=head1 SYNOPSIS
use Capture::Tiny ':all';
# capture from external command
($stdout, $stderr, $exit) = capture {
system( $cmd, @args );
};
# capture from arbitrary code (Perl or external)
($stdout, $stderr, @result) = capture {
# your code here
};
# capture partial or merged output
$stdout = capture_stdout { ... };
$stderr = capture_stderr { ... };
$merged = capture_merged { ... };
# tee output
($stdout, $stderr) = tee {
# your code here
};
$stdout = tee_stdout { ... };
$stderr = tee_stderr { ... };
$merged = tee_merged { ... };
=head1 DESCRIPTION
Capture::Tiny provides a simple, portable way to capture almost anything sent
to STDOUT or STDERR, regardless of whether it comes from Perl, from XS code or
from an external program. Optionally, output can be teed so that it is
captured while being passed through to the original filehandles. Yes, it even
works on Windows (usually). Stop guessing which of a dozen capturing modules
to use in any particular situation and just use this one.
=head1 USAGE
The following functions are available. None are exported by default.
=head2 capture
($stdout, $stderr, @result) = capture \&code;
$stdout = capture \&code;
The C<<< capture >>> function takes a code reference and returns what is sent to
STDOUT and STDERR as well as any return values from the code reference. In
scalar context, it returns only STDOUT. If no output was received for a
filehandle, it returns an empty string for that filehandle. Regardless of calling
context, all output is captured -- nothing is passed to the existing filehandles.
It is prototyped to take a subroutine reference as an argument. Thus, it
can be called in block form:
($stdout, $stderr) = capture {
# your code here ...
};
Note that the coderef is evaluated in list context. If you wish to force
scalar context on the return value, you must use the C<<< scalar >>> keyword.
($stdout, $stderr, $count) = capture {
my @list = qw/one two three/;
return scalar @list; # $count will be 3
};
Also note that within the coderef, the C<<< @_ >>> variable will be empty. So don't
use arguments from a surrounding subroutine without copying them to an array
first:
sub wont_work {
my ($stdout, $stderr) = capture { do_stuff( @_ ) }; # WRONG
...
}
sub will_work {
my @args = @_;
my ($stdout, $stderr) = capture { do_stuff( @args ) }; # RIGHT
...
}
Captures are normally done to an anonymous temporary filehandle. To
capture via a named file (e.g. to externally monitor a long-running capture),
provide custom filehandles as a trailing list of option pairs:
my $out_fh = IO::File->new("out.txt", "w+");
my $err_fh = IO::File->new("out.txt", "w+");
capture { ... } stdout => $out_fh, stderr => $err_fh;
The filehandles must be readE<sol>write and seekable. Modifying the files or
filehandles during a capture operation will give unpredictable results.
Existing IO layers on them may be changed by the capture.
When called in void context, C<<< capture >>> saves memory and time by
not reading back from the capture handles.
=head2 capture_stdout
($stdout, @result) = capture_stdout \&code;
$stdout = capture_stdout \&code;
The C<<< capture_stdout >>> function works just like C<<< capture >>> except only
STDOUT is captured. STDERR is not captured.
=head2 capture_stderr
($stderr, @result) = capture_stderr \&code;
$stderr = capture_stderr \&code;
The C<<< capture_stderr >>> function works just like C<<< capture >>> except only
STDERR is captured. STDOUT is not captured.
=head2 capture_merged
($merged, @result) = capture_merged \&code;
$merged = capture_merged \&code;
The C<<< capture_merged >>> function works just like C<<< capture >>> except STDOUT and
STDERR are merged. (Technically, STDERR is redirected to the same capturing
handle as STDOUT before executing the function.)
Caution: STDOUT and STDERR output in the merged result are not guaranteed to be
properly ordered due to buffering.
=head2 tee
($stdout, $stderr, @result) = tee \&code;
$stdout = tee \&code;
The C<<< tee >>> function works just like C<<< capture >>>, except that output is captured
as well as passed on to the original STDOUT and STDERR.
When called in void context, C<<< tee >>> saves memory and time by
not reading back from the capture handles, except when the
original STDOUT OR STDERR were tied or opened to a scalar
handle.
=head2 tee_stdout
($stdout, @result) = tee_stdout \&code;
$stdout = tee_stdout \&code;
The C<<< tee_stdout >>> function works just like C<<< tee >>> except only
STDOUT is teed. STDERR is not teed (output goes to STDERR as usual).
=head2 tee_stderr
($stderr, @result) = tee_stderr \&code;
$stderr = tee_stderr \&code;
The C<<< tee_stderr >>> function works just like C<<< tee >>> except only
STDERR is teed. STDOUT is not teed (output goes to STDOUT as usual).
=head2 tee_merged
($merged, @result) = tee_merged \&code;
$merged = tee_merged \&code;
The C<<< tee_merged >>> function works just like C<<< capture_merged >>> except that output
is captured as well as passed on to STDOUT.
#!/usr/bin/env perl
use strict;
use warnings;
use utf8;
use Test::More;
use IO::Handle;
use FindBin qw/ $Bin /;
use lib "$Bin/lib";
use Capture::Tiny qw/ capture_stderr /; # bundled under t/lib
# make sure all test output supports utf
binmode( \$_, ":utf8" ) for *STDERR, *STDOUT;
$_->autoflush(1) for *STDERR, *STDOUT;
our $CLASS = "Acme::Throw";
use_ok $CLASS;
$CLASS->import;
# throw and catch an exception
my $die_msg = "your mom";
my ($got_val, $got_err);
my $stderr = capture_stderr {
$got_val = eval { die "$die_msg\n"; };
$got_err = $@;
};
# make sure die still worked
is $got_val, undef, "die didn't break";
# determine what should be output before the exception message
my $msg = $CLASS->_msg;
my $exp_output = <<END;
(╯°□°）╯︵ â”»â”â”» $msg
$die_msg
END
# make sure original exception was not changed
is $got_err, "$die_msg\n", "orig exception unchanged";
#print STDERR "msg: [$msg] output: [$stderr]\n";
#TODO: {
# is $stderr, $exp_output, "NOW WITH 100% MORE RAGE";
#};
done_testing;
( run in 1.008 second using v1.01-cache-2.11-cpan-49f99fa48dc )