AnyEvent-DBI-MySQL
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{
"abstract" : "Asynchronous MySQL queries",
"author" : [
"Alex Efros <powerman@cpan.org>"
],
"dynamic_config" : 0,
"generated_by" : "Dist::Zilla version 5.047, Dist::Milla version v1.0.16, CPAN::Meta::Converter version 2.150005",
"license" : [
"mit"
],
"meta-spec" : {
"url" : "http://search.cpan.org/perldoc?CPAN::Meta::Spec",
---
abstract: 'Asynchronous MySQL queries'
author:
- 'Alex Efros <powerman@cpan.org>'
build_requires:
Test::Database: '0'
Test::Exception: '0'
Test::More: '0'
Time::HiRes: '0'
configure_requires:
Module::Build::Tiny: '0.034'
dynamic_config: 0
NAME
AnyEvent::DBI::MySQL - Asynchronous MySQL queries
VERSION
This document describes AnyEvent::DBI::MySQL version v2.1.0
SYNOPSIS
use AnyEvent::DBI::MySQL;
# get cached but not in use $dbh
# sync
$rv = $dbh->do('…');
$dbh->do('…', {async=>0}, sub { my ($rv, $dbh) = @_; … });
DESCRIPTION
This module is an AnyEvent user, you need to make sure that you use and
run a supported event loop.
This module implements asynchronous MySQL queries using "ASYNCHRONOUS
QUERIES" in DBD::mysql feature. Unlike AnyEvent::DBI it doesn't spawn
any processes.
You shouldn't use {RaiseError=>1} with this module and should check
returned values in your callback to detect errors. This is because with
{RaiseError=>1} exception will be thrown instead of calling your
callback function, which isn't what you want in most cases.
INTERFACE
The API is trivial: use it just like usual DBI, but instead of
expecting return value from functions which may block add one extra
parameter: callback. That callback will be executed with usual returned
value of used method in params (only exception is extra $dbh/$sth param
in do() and execute() for convenience).
SYNCHRONOUS QUERIES
In most cases to make usual synchronous query it's enough to don't
provide callback - use standard DBI params and it will work just like
usual DBI. Only exception is prepare()/execute() pair: you should use
{async=>0} attribute for prepare() to have synchronous execute().
For convenience, you can quickly turn asynchronous query to synchronous
by adding {async=>0} attribute - you don't have to rewrite code to
remove callback function. In this case your callback will be called
immediately after executing this synchronous query.
SUPPORTED DBI METHODS
connect
$dbh = AnyEvent::DBI::MySQL->connect(...);
DBD::mysql support only single asynchronous query per MySQL connection.
To make it easier to overcome this limitation provided connect()
constructor work using DBI->connect_cached() under the hood, but it
reuse only inactive $dbh - i.e. one which you didn't use anymore. So,
connect() guarantee to not return $dbh which is already in use in your
code. For example, in FastCGI or Mojolicious app you can safely use
connect() to get own $dbh per each incoming connection; after you send
response and close this connection that $dbh should automatically go
out of scope and become inactive (you can force this by $dbh=undef;);
after that this $dbh may be returned by connect() when handling next
incoming request. As result you should automatically get a pool of
lib/AnyEvent/DBI/MySQL.pm view on Meta::CPAN
return;
}
sub do { ## no critic(ProhibitBuiltinHomonyms)
my ($dbh, @args) = @_;
local $SIG{__WARN__} = sub { (my $msg=shift)=~s/ at .*//ms; carp $msg };
my $ref = ref $args[-1];
if ($ref eq 'CODE' || $ref eq 'AnyEvent::CondVar') {
my $data = $DATA[ $dbh->{$PRIVATE} ];
if ($data->{cb}) {
croak q{can't make more than one asynchronous query simultaneously};
}
$data->{cb} = pop @args;
$data->{h} = $dbh;
weaken($data->{h});
$args[1] //= {};
$args[1]->{async} //= 1;
if (!$args[1]->{async}) {
my $cb = delete $data->{cb};
my $h = delete $data->{h};
$cb->( $dbh->SUPER::do(@args), $h );
lib/AnyEvent/DBI/MySQL.pm view on Meta::CPAN
use Carp;
use Scalar::Util qw( weaken );
sub execute {
my ($sth, @args) = @_;
local $SIG{__WARN__} = sub { (my $msg=shift)=~s/ at .*//ms; carp $msg };
my $data = $DATA[ $sth->{$PRIVATE} ];
my $ref = ref $args[-1];
if ($ref eq 'CODE' || $ref eq 'AnyEvent::CondVar') {
if ($data->{cb}) {
croak q{can't make more than one asynchronous query simultaneously};
}
$data->{cb} = pop @args;
$data->{h} = $sth;
if (!$sth->{$PRIVATE_async}) {
my $cb = delete $data->{cb};
my $h = delete $data->{h};
$cb->( $sth->SUPER::execute(@args), $h );
return;
}
$sth->SUPER::execute(@args);
lib/AnyEvent/DBI/MySQL.pm view on Meta::CPAN
sub execute { return '0E0' };
1; # Magic true value required at end of module
__END__
=encoding utf8
=head1 NAME
AnyEvent::DBI::MySQL - Asynchronous MySQL queries
=head1 VERSION
This document describes AnyEvent::DBI::MySQL version v2.1.0
=head1 SYNOPSIS
use AnyEvent::DBI::MySQL;
lib/AnyEvent/DBI/MySQL.pm view on Meta::CPAN
# sync
$rv = $dbh->do('…');
$dbh->do('…', {async=>0}, sub { my ($rv, $dbh) = @_; … });
=head1 DESCRIPTION
This module is an L<AnyEvent> user, you need to make sure that you use and
run a supported event loop.
This module implements asynchronous MySQL queries using
L<DBD::mysql/"ASYNCHRONOUS QUERIES"> feature. Unlike L<AnyEvent::DBI> it
doesn't spawn any processes.
You shouldn't use C<< {RaiseError=>1} >> with this module and should check
returned values in your callback to detect errors. This is because with
C<< {RaiseError=>1} >> exception will be thrown B<instead> of calling your
callback function, which isn't what you want in most cases.
=head1 INTERFACE
The API is trivial: use it just like usual DBI, but instead of expecting
return value from functions which may block add one extra parameter: callback.
That callback will be executed with usual returned value of used method in
params (only exception is extra $dbh/$sth param in do() and execute() for
convenience).
=head2 SYNCHRONOUS QUERIES
In most cases to make usual synchronous query it's enough to don't provide
callback - use standard DBI params and it will work just like usual DBI.
Only exception is prepare()/execute() pair: you should use
C<< {async=>0} >> attribute for prepare() to have synchronous execute().
For convenience, you can quickly turn asynchronous query to synchronous by
adding C<< {async=>0} >> attribute - you don't have to rewrite code to
remove callback function. In this case your callback will be called
immediately after executing this synchronous query.
=head2 SUPPORTED DBI METHODS
=head3 connect
$dbh = AnyEvent::DBI::MySQL->connect(...);
L<DBD::mysql> support only single asynchronous query per MySQL connection.
To make it easier to overcome this limitation provided connect()
constructor work using DBI->connect_cached() under the hood, but it reuse
only inactive $dbh - i.e. one which you didn't use anymore. So, connect()
guarantee to not return $dbh which is already in use in your code.
For example, in FastCGI or Mojolicious app you can safely use connect() to
get own $dbh per each incoming connection; after you send response and
close this connection that $dbh should automatically go out of scope and
become inactive (you can force this by C<$dbh=undef;>); after that this
$dbh may be returned by connect() when handling next incoming request.
As result you should automatically get a pool of connected $dbh which size
( run in 0.363 second using v1.01-cache-2.11-cpan-0d8aa00de5b )