File Coverage

blib/lib/Mango.pm

Criterion	Covered	Total	%
statement	36	209	17.2
branch	0	94	0.0
condition	1	71	1.4
subroutine	12	40	30.0
pod	7	7	100.0
total	56	421	13.3

package Mango;
use Mojo::Base 'Mojo::EventEmitter';

use Carp 'croak';
use Hash::Util::FieldHash;
use Mango::BSON 'bson_doc';
use Mango::Database;
use Mango::Protocol;
use Mojo::IOLoop;
use Mojo::URL;
use Mojo::Util 'dumper';
use Scalar::Util 'weaken';

use constant DEBUG => $ENV{MANGO_DEBUG} || 0;
use constant DEFAULT_PORT => 27017;

has default_db  => 'admin';
has hosts       => sub { [['localhost']] };
has [qw(inactivity_timeout j)] => 0;
has ioloop => sub { Mojo::IOLoop->new };
has max_bson_size   => 16777216;
has max_connections => 5;
has [qw(max_write_batch_size wtimeout)] => 1000;
has protocol => sub { Mango::Protocol->new };
has w => 1;

# Private variables are not visible in the object's dump. This
# is good for security.
Hash::Util::FieldHash::fieldhash my %AUTH;

our $VERSION = '1.29';

sub DESTROY { shift->_cleanup }

sub backlog { scalar @{shift->{queue} || []} }

sub db {
  my ($self, $name) = @_;
  $name //= $self->default_db;
  my $db = Mango::Database->new(mango => $self, name => $name);
  weaken $db->{mango};
  return $db;
}

sub from_string {
  my ($self, $str) = @_;

  # Protocol
  return $self unless $str;
  my $url = Mojo::URL->new($str);
  croak qq{Invalid MongoDB connection string "$str"}
    unless $url->protocol eq 'mongodb';

  # Hosts
  my @hosts;
  /^([^,:]+)(?::(\d+))?/ and push @hosts, $2 ? [$1, $2] : [$1]
    for split /,/, join(':', map { $_ // '' } $url->host, $url->port);
  $self->hosts(\@hosts) if @hosts;

  # Database
  if (my $db = $url->path->parts->[0]) { $self->default_db($db) }

  # User and password
  if (($url->userinfo // '') =~ /^([^:]+):([^:]+)$/) {
    require Mango::Auth::SCRAM;
    $self->_auth(Mango::Auth::SCRAM->new)
      ->_auth->_credentials([$self->default_db, $1, $2]);
  }

  # Options
  my $query = $url->query;
  if (my $j       = $query->param('journal'))    { $self->j($j) }
  if (my $w       = $query->param('w'))          { $self->w($w) }
  if (my $timeout = $query->param('wtimeoutMS')) { $self->wtimeout($timeout) }

  return $self;
}

sub get_more { shift->_op('get_more', 1, @_) }

sub kill_cursors { shift->_op('kill_cursors', 0, @_) }

sub new { shift->SUPER::new->from_string(@_) }

sub query { shift->_op('query', 1, @_) }

sub _auth {
  my ($self, $mode) = @_;
  return $AUTH{$self} unless $mode;

  $AUTH{$self} = $mode;
  $AUTH{$self}->mango($self);
  weaken $AUTH{$self}->{mango};
  return $self;
}

sub _build {
  my ($self, $name) = (shift, shift);
  my $next = $self->_id;
  warn "-- Operation #$next ($name)\n@{[dumper [@_]]}" if DEBUG;
  my $method = "build_$name";
  return ($next, $self->protocol->$method($next, @_));
}

sub _cleanup {
  my $self = shift;
  return unless $self->_loop(0);

  # Clean up connections
  delete $self->{pid};
  my $connections = delete $self->{connections};
  for my $c (keys %$connections) {
    my $loop = $self->_loop($connections->{$c}{nb});
    $loop->remove($c) if $loop;
  }

  # Clean up active operations
  my $queue = delete $self->{queue} || [];
  $_->{last} && !$_->{start} && unshift @$queue, $_->{last}
    for values %$connections;
  $self->_finish(undef, $_->{cb}, 'Premature connection close') for @$queue;
}

sub _close {
  my ($self, $id) = @_;

  return unless my $c = delete $self->{connections}{$id};
  my $last = $c->{last};
  $self->_finish(undef, $last->{cb}, 'Premature connection close') if $last;
  $self->_connect($c->{nb}) if @{$self->{queue}};
}

sub _connect {
  my ($self, $nb, $hosts) = @_;

  my ($host, $port) = @{shift @{$hosts ||= [@{$self->hosts}]}};
  weaken $self;
  my $id;
  $id = $self->_loop($nb)->client(
    {address => $host, port => $port //= DEFAULT_PORT} => sub {
      my ($loop, $err, $stream) = @_;

      # Connection error (try next server)
      if ($err) {
        return $self->_error($id, $err) unless @$hosts;
        delete $self->{connections}{$id};
        return $self->_connect($nb, $hosts);
      }

      # Connection established
      $stream->timeout($self->inactivity_timeout);
      $stream->on(close => sub { $self && $self->_close($id) });
      $stream->on(error => sub { $self && $self->_error($id, pop) });
      $stream->on(read => sub { $self->_read($id, pop) });

      # Check node information with "isMaster" command
      my $cb = sub { shift->_master($id, $nb, $hosts, pop) };
      $self->_fast($id, $self->default_db, {isMaster => 1}, $cb);
    }
  );
  $self->{connections}{$id} = { nb => $nb, start => 1 };

  my $num = scalar keys %{$self->{connections}};
  warn "-- New connection ($host:$port:$num)\n" if DEBUG;
}

sub _error {
  my ($self, $id, $err) = @_;

  return unless my $c = delete $self->{connections}{$id};
  $self->_loop($c->{nb})->remove($id);

  my $last = $c->{last} // shift @{$self->{queue}};
  $self->_finish(undef, $last->{cb}, $err) if $last;
}

sub _fast {
  my ($self, $id, $db, $command, $cb) = @_;

  # Handle errors
  my $wrapper = sub {
    my ($self, $err, $reply) = @_;

    my $doc = $reply->{docs}[0];
    $err ||= $self->protocol->command_error($doc);
    return $self->$cb(undef, $doc) unless $err;

    return unless my $last = shift @{$self->{queue}};
    $self->_finish(undef, $last->{cb}, $err);
  };

  # Skip the queue and run command right away
  my ($next, $msg)
    = $self->_build('query', "$db.\$cmd", {}, 0, -1, $command, {});
  $self->{connections}{$id}{fast}
    = {id => $next, safe => 1, msg => $msg, cb => $wrapper};
  $self->_next;
}

sub _finish {
  my ($self, $reply, $cb, $err) = @_;
  $self->$cb($err || $self->protocol->query_failure($reply), $reply);
}

sub _id { $_[0]{id} = $_[0]->protocol->next_id($_[0]{id} // 0) }

sub _loop { $_[1] ? Mojo::IOLoop->singleton : $_[0]->ioloop }

sub _master {
  my ($self, $id, $nb, $hosts, $doc) = @_;

  # Check version
  return $self->_error($id, 'MongoDB version 3.0 required')
    unless ($doc->{maxWireVersion} || 0) >= 3;

  # Continue with authentication if we are connected to the primary
  if ($doc->{ismaster}) {
    return $self->_auth
      ? $self->_auth->_authenticate($id)
      : $self->emit(connection => $id)->_next;
  }

  # Get primary and try to connect again
  unshift @$hosts, [$1, $2] if ($doc->{primary} // '') =~ /^(.+):(\d+)$/;
  return $self->_error($id, "Couldn't find primary node") unless @$hosts;
  delete $self->{connections}{$id};
  $self->_loop($nb)->remove($id);
  $self->_connect($nb, $hosts);
}

sub _next {
  my ($self, $op) = @_;

  # Make sure all connections are saturated
  push @{$self->{queue} ||= []}, $op if $op;
  my $connections = $self->{connections};
  my $start;
  $self->_write($_) and $start++ for keys %$connections;

  # Check if we need a blocking connection
  return unless $op;
  my @ids = keys %$connections;
  return $self->_connect(0)
    if !$op->{nb} && !grep { !$connections->{$_}{nb} } @ids;

  # Check if we need more non-blocking connections
  $self->_connect(1)
    if !$start && @{$self->{queue}} && @ids < $self->max_connections;
}

sub _op {
  my ($self, $op, $safe) = (shift, shift, shift);
  my $cb = ref $_[-1] eq 'CODE' ? pop : undef;
  my ($next, $msg) = $self->_build($op, @_);
  $self->_start(
    {id => $next, safe => $safe, msg => $msg, nb => !!$cb, cb => $cb});
}

sub _read {
  my ($self, $id, $chunk) = @_;

  my $c = $self->{connections}{$id};
  $c->{buffer} .= $chunk;
  while (my $reply = $self->protocol->parse_reply(\$c->{buffer})) {
    warn "-- Client <<< Server (#$reply->{to})\n@{[dumper $reply]}" if DEBUG;
    next unless $reply->{to} == $c->{last}{id};
    $self->_finish($reply, (delete $c->{last})->{cb});
  }
  $self->_next;
}

sub _start {
  my ($self, $op) = @_;

  # Fork safety
  $self->_cleanup unless ($self->{pid} //= $$) eq $$;

  # Non-blocking
  return $self->_next($op) if $op->{cb};

  # Blocking
  my ($err, $reply);
  $op->{cb} = sub { shift->ioloop->stop; ($err, $reply) = @_ };
  $self->_next($op);
  $self->ioloop->start;
  return $err ? croak $err : $reply;
}

sub _write {
  my ($self, $id) = @_;

  # Make sure connection has not been corrupted while event loop was stopped
  my $c = $self->{connections}{$id};
  return $c->{start} if $c->{last};
  my $loop = $self->_loop($c->{nb});
  return undef unless my $stream = $loop->stream($id);
  if (!$loop->is_running && $stream->is_readable) {
    $stream->close;
    return undef;
  }

  # Fast operation
  delete $c->{start} unless my $last = delete $c->{fast};

  # Blocking operations have a higher precedence
  return $c->{start}
    unless $last || ($c->{nb} xor !($self->{queue}->[-1] || {})->{nb});
  $last ||= $c->{nb} ? shift @{$self->{queue}} : pop @{$self->{queue}};

  return $c->{start} unless $c->{last} = $last;
  warn "-- Client >>> Server (#$last->{id})\n" if DEBUG;
  $stream->write(delete $last->{msg});

  # Unsafe operations are done when they are written
  return $c->{start} if $last->{safe};
  weaken $self;
  $stream->write('', sub { $self->_finish(undef, delete($c->{last})->{cb}) });
  return $c->{start};
}

1;

=encoding utf8

=head1 NAME

Mango - Pure-Perl non-blocking I/O MongoDB driver

=head1 SYNOPSIS

  use Mango;

  # Declare a Mango helper
  sub mango { state $m = Mango->new('mongodb://localhost:27017') }
  # or in a Mojolicious::Lite app
  helper mango => sub { state $m = Mango->new('mongodb://localhost:27017') };

  # Insert document
  my $oid   = mango->db('test')->collection('foo')->insert({bar => 'baz'});

  # Find document
  my $doc = mango->db('test')->collection('foo')->find_one({bar => 'baz'});
  say $doc->{bar};

  # Update document
  mango->db('test')->collection('foo')
    ->update({bar => 'baz'}, {bar => 'yada'});

  # Remove document
  mango->db('test')->collection('foo')->remove({bar => 'yada'});

  # Insert document with special BSON types
  use Mango::BSON ':bson';
  my $oid = mango->db('test')->collection('foo')
    ->insert({data => bson_bin("\x00\x01"), now => bson_time});

  # Non-blocking concurrent find
  my $delay = Mojo::IOLoop->delay(sub {
    my ($delay, @docs) = @_;
    ...
  });
  for my $name (qw(sri marty)) {
    my $end = $delay->begin(0);
    mango->db('test')->collection('users')->find({name => $name})->all(sub {
      my ($cursor, $err, $docs) = @_;
      $end->(@$docs);
    });
  }
  $delay->wait;

  # Event loops such as AnyEvent are supported through EV
  use EV;
  use AnyEvent;
  my $cv = AE::cv;
  mango->db('test')->command(buildInfo => sub {
    my ($db, $err, $doc) = @_;
    $cv->send($doc->{version});
  });
  say $cv->recv;

=head1 DESCRIPTION

L is a pure-Perl non-blocking I/O MongoDB driver, optimized for use
with the L real-time web framework, and with multiple event loop
support. Since MongoDB is still changing rapidly, only the latest stable
version is supported.

For MongoDB 2.6 support, use L 1.16.

To learn more about MongoDB you should take a look at the
L, the documentation included
in this distribution is no replacement for it.

Look at L for CRUD operations.

Many arguments passed to methods as well as values of attributes get
serialized to BSON with L, which provides many helper functions
you can use to generate data types that are not available natively in Perl.
All connections will be reset automatically if a new process has been forked,
this allows multiple processes to share the same L object safely.

For better scalability (epoll, kqueue) and to provide IPv6, SOCKS5 as well as
TLS support, the optional modules L (4.0+), L (0.20+),
L (0.64+) and L (1.84+) will be used
automatically if they are installed. Individual features can also be disabled
with the C, C and C environment
variables.

=head1 EVENTS

L inherits all events from L and can emit the
following new ones.

=head2 connection

  $mango->on(connection => sub {
    my ($mango, $id) = @_;
    ...
  });

Emitted when a new connection has been established.

=head1 ATTRIBUTES

L implements the following attributes.

=head2 default_db

  my $name = $mango->default_db;
  $mango   = $mango->default_db('test');

Default database, defaults to C.

=head2 hosts

  my $hosts = $mango->hosts;
  $mango    = $mango->hosts([['localhost', 3000], ['localhost', 4000]]);

Servers to connect to, defaults to C and port C<27017>.

=head2 inactivity_timeout

  my $timeout = $mango->inactivity_timeout;
  $mango      = $mango->inactivity_timeout(15);

Maximum amount of time in seconds a connection can be inactive before getting
closed, defaults to C<0>. Setting the value to C<0> will allow connections to
be inactive indefinitely.

=head2 ioloop

  my $loop = $mango->ioloop;
  $mango   = $mango->ioloop(Mojo::IOLoop->new);

Event loop object to use for blocking I/O operations, defaults to a
L object.

=head2 j

  my $j  = $mango->j;
  $mango = $mango->j(1);

Wait for all operations to have reached the journal, defaults to C<0>.

=head2 max_bson_size

  my $max = $mango->max_bson_size;
  $mango  = $mango->max_bson_size(16777216);

Maximum size for BSON documents in bytes, defaults to C<16777216> (16MB).

=head2 max_connections

  my $max = $mango->max_connections;
  $mango  = $mango->max_connections(5);

Maximum number of connections to use for non-blocking operations, defaults to
C<5>.

=head2 max_write_batch_size

  my $max = $mango->max_write_batch_size;
  $mango  = $mango->max_write_batch_size(1000);

 Maximum number of write operations to batch together, defaults to C<1000>.

=head2 protocol

  my $protocol = $mango->protocol;
  $mango       = $mango->protocol(Mango::Protocol->new);

Protocol handler, defaults to a L object.

=head2 w

  my $w  = $mango->w;
  $mango = $mango->w(2);

Wait for all operations to have reached at least this many servers, C<1>
indicates just primary, C<2> indicates primary and at least one secondary,
defaults to C<1>.

=head2 wtimeout

  my $timeout = $mango->wtimeout;
  $mango      = $mango->wtimeout(1);

Timeout for write propagation in milliseconds, defaults to C<1000>.

=head1 METHODS

L inherits all methods from L and implements the following
new ones.

=head2 backlog

  my $num = $mango->backlog;

Number of queued operations that have not yet been assigned to a connection.

=head2 db

  my $db = $mango->db;
  my $db = $mango->db('test');

Build L object for database, uses L if no name
is provided. Note that the reference L is weakened,
so the L object needs to be referenced elsewhere as well.

=head2 from_string

  $mango
    = $mango->from_string('mongodb://sri:s3cret@localhost:3000/test?w=2');

Parse configuration from connection string.

=head2 get_more

  my $reply = $mango->get_more($namespace, $return, $cursor);

Perform low level C operation. You can also append a callback to
perform operation non-blocking.

  $mango->get_more(($namespace, $return, $cursor) => sub {
    my ($mango, $err, $reply) = @_;
    ...
  });
  Mojo::IOLoop->start unless Mojo::IOLoop->is_running;

=head2 kill_cursors

  $mango->kill_cursors(@ids);

Perform low level C operation. You can also append a callback to
perform operation non-blocking.

    $mango->kill_cursors(@ids => sub {
      my ($mango, $err) = @_;
      ...
    });
    Mojo::IOLoop->start unless Mojo::IOLoop->is_running;

=head2 new

  my $mango = Mango->new;
  my $mango = Mango->new('mongodb://sri:s3cret@localhost:3000/test?w=2');

Construct a new L object and parse connection string with
L if necessary.

Not that is is B recommended to build your Mango object inside
a helper function like shown in the synopsis. This is because the Mango's
object reference inside L objects is weakened to avoid
memory leaks. This means your Mango instance is quickly going to get
undefined after you use the C method. So, use a helper to prevent that.

If a username and password are provided, Mango will try to authenticate using
SCRAM-SHA1. B this will require L which is not
installed by default.

=head2 query

  my $reply
    = $mango->query($namespace, $flags, $skip, $return, $query, $fields);

Perform low level C operation. You can also append a callback to
perform operation non-blocking.

  $mango->query(($namespace, $flags, $skip, $return, $query, $fields) => sub {
    my ($mango, $err, $reply) = @_;
    ...
  });
  Mojo::IOLoop->start unless Mojo::IOLoop->is_running;

=head1 DEBUGGING

You can set the C environment variable to get some advanced
diagnostics information printed to C.

  MANGO_DEBUG=1

=head1 SPONSORS

Some of the work on this distribution has been sponsored by
L, thank you!

=head1 AUTHOR

Sebastian Riedel, C.

Current maintainer: Olivier Duclos C.

=head1 CREDITS

In alphabetical order:

=over 2

alexbyk

Andrey Khozov

Colin Cyr

=back

=head1 COPYRIGHT AND LICENSE

Copyright (C) 2013-2014, Sebastian Riedel.

This program is free software, you can redistribute it and/or modify it under
the terms of the Artistic License version 2.0.

=head1 SEE ALSO

L, L,
L.

=cut