AnyEvent-CouchDB
view release on metacpan or search on metacpan
lib/AnyEvent/CouchDB.pm view on Meta::CPAN
body => $body,
$cb
);
$cv;
}
1;
__END__
=head1 NAME
AnyEvent::CouchDB - a non-blocking CouchDB client based on jquery.couch.js
=head1 SYNOPSIS
Getting information about a CouchDB server:
use AnyEvent::CouchDB;
use Data::Dump 'pp';
my $couch = couch('http://localhost:5984/');
print pp( $couch->all_dbs->recv ), "\n";
print pp( $couch->info->recv ), "\n";
Get an object representing a CouchDB database:
my $db = $couch->db('database');
$db = couchdb('database');
$db = couchdb('http://somewhere.com:7777/database/');
With authentication:
# user is the username and s3cret is the password
$db = couchdb('http://user:s3cret@somewhere.com:7777/database');
Work with individual CouchDB documents;
my $user = $db->open_doc('~larry')->recv;
$user->{name} = "larry";
$db->save_doc($user)->recv;
Query a view:
$db->view('users/all', { startkey => 'b', endkey => 'bZZZ' })->recv
Finally, an asynchronous example:
# Calling cb allow you to set a callback that will run when results are available.
$db->all_docs->cb(sub {
my ($cv) = @_;
print pp( $cv->recv ), "\n";
});
# However, you have to be in an event loop at some point in time.
AnyEvent->condvar->recv;
=head1 DESCRIPTION
AnyEvent::CouchDB is a non-blocking CouchDB client implemented on top of the
L<AnyEvent> framework. Using this library will give you the ability to run
many CouchDB requests asynchronously, and it was intended to be used within
a L<Coro>+L<AnyEvent> environment. However, it can also be used synchronously
if you want.
Its API is based on jquery.couch.js, but we've adapted the API slightly so that
it makes sense in an asynchronous Perl environment.
=head2 AnyEvent condvars
The main thing you have to remember is that all the data retrieval methods
return an AnyEvent condvar, C<$cv>. If you want the actual data from the
request, there are a few things you can do.
You may have noticed that many of the examples in the SYNOPSIS call C<recv>
on the condvar. You're allowed to do this under 2 circumstances:
=over 4
=item Either you're in a main program,
Main programs are "allowed to call C<recv> blockingly", according to the
author of L<AnyEvent>.
=item or you're in a Coro + AnyEvent environment.
When you call C<recv> inside a coroutine, only that coroutine is blocked
while other coroutines remain active. Thus, the program as a whole is
still responsive.
=back
If you're not using Coro, and you don't want your whole program to block,
what you should do is call C<cb> on the condvar, and give it a coderef to
execute when the results come back. The coderef will be given a condvar
as a parameter, and it can call C<recv> on it to get the data. The final
example in the SYNOPSIS gives a brief example of this.
Also note that C<recv> will throw an exception if the request fails, so be
prepared to catch exceptions where appropriate.
Please read the L<AnyEvent> documentation for more information on the proper
use of condvars.
=head2 The \%options Parameter
Many data retrieval methods will take an optional C<\%options> hashref.
Most of these options get turned into CGI query parameters. The standard
CouchDB parameters are as follows:
=over 4
=item key=keyvalue
This lets you pick out one document with the specified key value.
=item startkey=keyvalue
This makes it so that lists start with a key value that is greater than or
equal to the specified key value.
( run in 2.820 seconds using v1.01-cache-2.11-cpan-13bb782fe5a )