NAME

Net::Curl::Easy - Perl interface for curl_easy_* functions

SYNOPSIS

Direct use.

use Net::Curl::Easy qw(:constants);

my $easy = Net::Curl::Easy->new();
$easy->setopt( CURLOPT_URL, "http://example.com/" );

$easy->perform();

Build your own browser.

package MyBrowser;
use Net::Curl::Easy qw(/^CURLOPT_/ /^CURLINFO_/);
use base qw(Net::Curl::Easy);

sub new
{
    my $class = shift;
    my $self = $class->SUPER::new( { head => '', body => ''} );
    $self->setopt( CURLOPT_USERAGENT, "MyBrowser v0.1" );
    $self->setopt( CURLOPT_FOLLOWLOCATION, 1 );
    $self->setopt( CURLOPT_COOKIEFILE, "" ); # enable cookie session
    $self->setopt( CURLOPT_FILE, \$self->{body} );
    $self->setopt( CURLOPT_HEADERDATA, \$self->{head} );
    return $self;
}

sub get
{
    my ( $self, $uri ) = @_;
    $self->setopt( CURLOPT_URL, $uri );
    @$self{qw(head body)} = ('', '');
    $self->perform();
    my $ref = $self->getinfo( CURLINFO_EFFECTIVE_URL );
    $self->setopt( CURLOPT_REFERER, $ref );
    return @$self{qw(head body)};
}

DESCRIPTION

This module wraps easy handle from libcurl and all related functions and constants. It does not export by default anything, but constants can be exported upon request.

use Net::Curl::Easy qw(:constants);

CONSTRUCTOR

new( [BASE] )

Creates new Net::Curl::Easy object. If BASE is specified it will be used as object base, otherwise an empty hash will be used. BASE must be a valid reference which has not been blessed already. It will not be used by the object.

my $easy = Net::Curl::Easy->new( [qw(my very private data)] );

Calls curl_easy_init(3) and presets some defaults.

METHODS

duphandle( [BASE] )

Clone Net::Curl::Easy object. It will not copy BASE from the source object. If you want it copied you must do it on your own.

my $hash_clone = $easy->duphandle( { %$easy } );

use Storable qw(dclone);
my $deep_clone = $easy->duphandle( dclone( $easy ) );

Calls curl_easy_duphandle(3).

setopt( OPTION, VALUE )

Set an option. OPTION is a numeric value, use one of CURLOPT_* constants. VALUE depends on whatever that option expects.

$easy->setopt( Net::Curl::Easy::CURLOPT_URL, $uri );

Calls curl_easy_setopt(3). Throws "Net::Curl::Easy::Code" on error.

pushopt( OPTION, ARRAYREF )

If option expects a slist, specified array will be appended instead of replacing the old slist.

$easy->pushopt( Net::Curl::Easy::CURLOPT_HTTPHEADER,
    ['More: headers'] );

Builds a slist and calls curl_easy_setopt(3). Throws "Net::Curl::Easy::Code" on error.

reset( )

Reinitializes easy handle (was broken before v0.27!).

$easy->reset();

Calls curl_easy_reset(3) and presets some defaults.

perform( )

Perform upload and download process.

$easy->perform();

Calls curl_easy_perform(3). Rethrows exceptions from callbacks. Throws "Net::Curl::Easy::Code" on other errors.

getinfo( OPTION )

Retrieve a value. OPTION is one of CURLINFO_* constants.

my $socket = $self->getinfo( CURLINFO_LASTSOCKET );

Calls curl_easy_getinfo(3). Throws "Net::Curl::Easy::Code" on error.

pause( )

Pause the transfer.

Calls curl_easy_pause(3). Not available in curl before 7.18.0. Throws "Net::Curl::Easy::Code" on error.

send( BUFFER )

Send raw data.

$easy->send( $data );

Calls curl_easy_send(3). Not available in curl before 7.18.2. Throws "Net::Curl::Easy::Code" on error.

recv( BUFFER, MAXLENGTH )

Receive raw data. Will receive at most MAXLENGTH bytes. New data will be concatenated to BUFFER.

$easy->recv( $buffer, $len );

Calls curl_easy_recv(3). Not available in curl before 7.18.2. Throws "Net::Curl::Easy::Code" on error.

error( )

Get last error message.

See information on CURLOPT_ERRORBUFFER in curl_easy_setopt(3) for a longer description.

my $error = $easy->error();
print "Last error: $error\n";
multi( )

If easy object is associated with any multi handles, it will return that multi handle.

my $multi = $easy->multi;

Use $multi->add_handle() to attach the easy object to the multi interface.

share( )

If share object is attached to this easy handle, this method will return that share object.

my $share = $easy->share;

Use setopt() with CURLOPT_SHARE option to attach the share object.

form( )

If form object is attached to this easy handle, this method will return that form object.

my $form = $easy->form;

Use setopt() with CURLOPT_HTTPPOST option to attach the share object.

FUNCTIONS

None of those functions are exported, you must use fully qualified names.

strerror( [WHATEVER], CODE )

Return a string for error code CODE.

my $message = Net::Curl::Easy::strerror(
    Net::Curl::Easy::CURLE_OK
);

Calls curl_easy_strerror(3).

CONSTANTS

Net::Curl::Easy contains all the constants that do not form part of any other Net::Curl modules. List below describes only the ones that behave differently than their C counterparts.

CURLOPT_PRIVATE

setopt() does not allow to use this constant. Hide any private data in your base object.

CURLOPT_ERRORBUFFER

setopt() does not allow to use this constant. You can always retrieve latest error message with $east->error() method.

CALLBACKS

Reffer to libcurl documentation for more detailed info on each of those. Callbacks can be set using setopt() method.

$easy->setopt( CURLOPT_somethingFUNCTION, \&callback_function );
# or
$easy->setopt( CURLOPT_somethingFUNCTION, "callback_method" );
$easy->setopt( CURLOPT_somethingDATA, [qw(any additional data
    you want)] );
CURLOPT_WRITEFUNCTION ( CURLOPT_WRITEDATA )

write callback receives 3 arguments: easy object, data to write, and whatever CURLOPT_WRITEDATA was set to. It must return number of data bytes.

sub cb_write {
    my ( $easy, $data, $uservar ) = @_;
    # ... process ...
    return CURL_WRITEFUNC_PAUSE if $want_pause;
    return length $data;
}
CURLOPT_READFUNCTION ( CURLOPT_READDATA )

read callback receives 3 arguments: easy object, maximum data length, and CURLOPT_READDATA value. It must return either a reference to data read or one of numeric values: 0 - transfer completed, CURL_READFUNC_ABORT - abort upload, CURL_READFUNC_PAUSE - pause upload. Reference to any value that is zero in length ("", undef) will also signalize completed transfer.

sub cb_read {
    my ( $easy, $maxlen, $uservar ) = @_;
    # ... read $data, $maxlen ...
    return \$data;
}
CURLOPT_IOCTLFUNCTION ( CURLOPT_IOCTLDATA )

ioctl callback receives 3 arguments: easy object, ioctl command, and CURLOPT_IOCTLDATA value. It must return a curlioerr value.

sub cb_ioctl {
    my ( $easy, $command, $uservar ) = @_;

    if ( $command == CURLIOCMD_RESTARTREAD ) {
        if ( restart_read() ) {
            return CURLIOE_OK;
        } else {
            return CURLIOE_FAILRESTART;
        }
    }
    return CURLIOE_UNKNOWNCMD;
}
CURLOPT_SEEKFUNCTION ( CURLOPT_SEEKDATA ) 7.18.0+

seek callback receives 4 arguments: easy object, offset / position, origin / whence, and CURLOPT_SEEKDATA value. Must return one of CURL_SEEKFUNC_* values.

use Fcntl qw(:seek);
sub cb_seek {
    my ( $easy, $offset, $origin, $uservar ) = @_;
    if ( $origin = SEEK_SET ) {
        if ( seek SOMETHING, $offset, SEEK_SET ) {
            return CURL_SEEKFUNC_OK;
        }
        return CURL_SEEKFUNC_CANTSEEK;
    }
    return CURL_SEEKFUNC_FAIL
}
CURLOPT_SOCKOPTFUNCTION ( CURLOPT_SOCKOPTDATA ) 7.15.6+

sockopt callback receives 4 arguments: easy object, socket fd, socket purpose, and CURLOPT_SOCKOPTDATA value. Is should return one of CURL_SOCKOPT_* values.

sub cb_sockopt {
    my ( $easy, $socket, $purpose, $uservar ) = @_;
    # ... do something with the socket ...
    return CURL_SOCKOPT_OK;
}
CURLOPT_OPENSOCKETFUNCTION ( CURLOPT_OPENSOCKETDATA ) 7.17.1+

opensocket callback receives 4 arguments: easy object, socket purpose, address structure (in form of a hashref), and CURLOPT_OPENSOCKETDATA value. The address structure has following numeric values: "family", "socktype", "protocol"; and "addr" in binary form. Use Socket module to decode "addr" field. You are also allowed to change those values.

Callback must return fileno of the socket or CURL_SOCKET_BAD on error.

use Socket;
sub cb_opensocket {
    my ( $easy, $purpose, $address, $uservar ) = @_;

    # decode addr information
    my ( $port, $ip ) = unpack_sockaddr_in( $address->{addr} );
    my $ip_string = inet_ntoa( $ip );

    # open the socket
    socket my $socket, $address->{family}, $address->{socktype},
        $address->{protocol};

    # save it somewhere so perl won't close the socket
    $opened_sockets{ fileno( $socket ) } = $socket;

    # return the socket
    return fileno $socket;
}
CURLOPT_CLOSESOCKETFUNCTION ( CURLOPT_CLOSESOCKETDATA ) 7.21.7+

closesocket callback receives 3 arguments: easy object, socket fileno, and CURLOPT_CLOSESOCKETDATA value.

sub cb_closesocket {
    my ( $easy, $fileno, $uservar ) = @_;
    my $socket = delete $opened_sockets{ $fileno };
    close $socket;
}
CURLOPT_PROGRESSFUNCTION ( CURLOPT_PROGRESSDATA )

Progress callback receives 6 arguments: easy object, dltotal, dlnow, ultotal, ulnow and CURLOPT_PROGRESSDATA value. It should return 0.

sub cb_progress {
    my ( $easy, $dltotal, $dlnow, $ultotal, $ulnow, $uservar ) = @_;
    # ... display progress ...
    return 0;
}
CURLOPT_HEADERFUNCTION ( CURLOPT_WRITEHEADER )

Behaviour is the same as in write callback. Callback is called once for every header line.

CURLOPT_DEBUGFUNCTION ( CURLOPT_DEBUGDATA )

Debug callback receives 4 arguments: easy object, message type, debug data and CURLOPT_DEBUGDATA value. Must return 0.

sub cb_debug {
    my ( $easy, $type, $data, $uservar ) = @_;
    # ... display debug info ...
    return 0;
}
CURLOPT_SSL_CTX_FUNCTION ( CURLOPT_SSL_CTX_DATA )

Not supported, probably will never be.

CURLOPT_INTERLEAVEFUNCTION ( CURLOPT_INTERLEAVEDATA ) 7.20.0+

Behaviour is the same as in write callback.

CURLOPT_CHUNK_BGN_FUNCTION ( CURLOPT_CHUNK_DATA ) 7.21.0+

chunk_bgn callback receives 4 arguments: easy object, fileinfo structure (in form of a hashref), number of remaining chunks, and CURLOPT_CHUNK_DATA value. It must return one of CURL_CHUNK_BGN_FUNC_* values.

sub cb_chunk_bgn {
    my ( $easy, $fileinfo, $remaining, $uservar ) = @_;

    if ( exists $fileinfo->{filetype} and
            $fileinfo->{filetype} != CURLFILETYPE_FILE ) {
        # download regular files only
        return CURL_CHUNK_BGN_FUNC_SKIP;
    }
    my $filename = "unknown." . $remaining;
    $filename = $fileinfo->{filename}
        if defined $fileinfo->{filename};

    open $easy->{myfile}, '>', $filename
        or return CURL_CHUNK_BGN_FUNC_FAIL;

    return CURL_CHUNK_BGN_FUNC_OK;
}
CURLOPT_CHUNK_END_FUNCTION ( CURLOPT_CHUNK_DATA ) 7.21.0+

chunk_end callback receives 2 arguments: easy object and CURLOPT_CHUNK_DATA value. Must return one of CURL_CHUNK_END_FUNC_* values.

sub cb_chunk_end {
    my ( $easy, $uservar ) = @_;
    # ... close $easy-{myfile} ...
    return CURL_CHUNK_END_FUNC_OK;
}
CURLOPT_FNMATCH_FUNCTION ( CURLOPT_FNMATCH_DATA ) 7.21.0+

fnmatch callback receives 4 arguments: easy object, pattern, string, and CURLOPT_FNMATCH_DATA value. Must return one of CURL_FNMATCHFUNC_* values.

sub cb_fnmatch {
    my ( $easy, $pattern, $string, $uservar ) = @_;
    return ( $string =~ m/$pattern/i
        ? CURL_FNMATCHFUNC_MATCH
        : CURL_FNMATCHFUNC_NOMATCH );
}
CURLOPT_SSH_KEYFUNCTION ( CURLOPT_SSH_KEYDATA ) 7.19.6+

sshkey callback receives 4 arguments: easy object, known key, found key, khmatch status and CURLOPT_SSH_KEYDATA value. Must return one of CURLKHSTAT_* values.

sub cb_sshkey {
    my ( $easy, $knownkey, $foundkey, $khmatch, $uservar ) = @_;
    return CURLKHSTAT_FINE_ADD_TO_FILE;
}

Net::Curl::Easy::Code

Most Net::Curl::Easy methods on failure throw a Net::Curl::Easy::Code error object. It has both numeric value and, when used as string, it calls strerror() function to display a nice message.

eval {
    $easy->somemethod();
};
if ( ref $@ eq "Net::Curl::Easy::Code" ) {
    if ( $@ == CURLE_SOME_ERROR_WE_EXPECTED ) {
        warn "Expected error, continuing\n";
    } else {
        die "Unexpected curl error: $@\n";
    }
} else {
    # rethrow everyting else
    die $@;
}

SEE ALSO

Net::Curl Net::Curl::Multi Net::Curl::examples libcurl-easy(3) libcurl-errors(3)

COPYRIGHT

Copyright (c) 2011 Przemyslaw Iskra <sparky at pld-linux.org>.

You may opt to use, copy, modify, merge, publish, distribute and/or sell copies of the Software, and permit persons to whom the Software is furnished to do so, under the terms of the MPL or the MIT/X-derivate licenses. You may pick one of these licenses.