AnyEvent::Tools(3pm)

📦
version 0.12 · 2 versions
, in debian bookworm, debian trixie, ubuntu jammy, ubuntu noble

💖 AnyEvent::Tools 💖

okay bestie, gather round, because this is the AnyEvent::Tools page from the User Contributed Perl Documentation and it's literally a whole instrument collection for AnyEvent and I'm obsessed. 🎀

It's an instrument collection for AnyEvent, periodt.

✨ SYNOPSIS ✨

🫧 Objects pool

use AnyEvent::Tools qw(pool);
my $dbh1 = ...
my $dbh2 = ...

...
my $dbhN = ...

my $pool = pool($dbh1, $dbh2, $dbh3, ..., $dbhN);

# later
...
$pool->get(sub {
    my ($guard, $dbh) = @_;
    ... # Enjoy $dbh here

    undef $guard;           # the other process can use the $dbh
});

🔒 Mutexes

use AnyEvent::Tools qw(mutex);

my $dbh = new AnyEvent::DBI(bla);
my $mutex_dbh = mutex;

sub some_callback() {
    ...
    $mutex_dbh->lock(sub {
        my ($mutex_guard) = @_;

        $dbh->exec("SELECT * FROM table", sub {
            my ($dbh, $rows, $rv) = @_;
            ...

            undef $mutex_guard; # unlock mutex
        });

    });
}

🦋 Read/Write mutexes

# Your data
my @shared_data;

use AnyEvent::Tools qw(rw_mutex);
use AnyEvent::Tools qw(:mutex);     # mutex and rw_mutex
my $rw_mutex = rw_mutex;

sub some_callback() {
    ...
    $rw_mutex->rlock(sub {
        my ($mutex_guard) = @_;

        ...

        # You can read Your data here
        ...
        # later
        ... = sub {
            # done

            undef $mutex_guard;     # unlock mutex
        }

    });
}

sub other_callback() {
    ...
    $rw_mutex->wlock(sub {
        my ($mutex_guard) = @_;
        ...

        # You can write Your data here
        ...
        # later
        ... = sub {
            # done

            undef $mutex_guard;     # unlock mutex
        }

    });
}

🔁 Foreaches

use AnyEvent::Tools qw(:foreach);

async_repeat $count,
    sub {
        my ($guard, $iteration, $first_flag, $last_flag) = @_;

        ... do something $count times
    },
    sub {
        ... # do something after all cycles
    };

async_foreach
        \@array,
        sub {
            my ($guard, $element, $index, $first_flag, $last_flag) = @_;

            ... # do something with $array[$index];
        },
        sub {
            ... # do something after all cycles

        };

async_foreach
        \%hash,
        sub {
            my ($guard, $key, $value, $first_flag, $last_flag) = @_;

            ... # do something with $hash{$key};
        },
        sub {
            my ($guard) = @_;

            ... # do something after all cycles

        };

🍓 Buffers

use AnyEvent::Tools ':pool';    # pool and buffer
use AnyEvent::Tools qw(buffer); # buffer only
my $buffer = buffer;
$buffer->on_flush( sub { ($guard, $objects_aref) = @_; .... });

...

$buffer->push($obj1);
$buffer->push($obj2);
$buffer->push($obj3);
$buffer->push($obj4);

$buffer->flush;

# autoflush after 30 second
$buffer->interval(30);

# autoflush if it contains more than 50 elements
$buffer->size(50);

🌸 DESCRIPTION 🌸

so here's the vibe: even though the event machine gets started as one single process, you may highkey want to share one resource between a lot of subprocesses. 💅 And sometimes you also want to do something with a lot of data that's just sitting there in hashes/arrays. That's the whole point, bestie.

👑 FUNCTIONS 👑

🔐 mutex

returns unlocked mutex. slay.

This object provides the following methods:

lock(CODEREF)

You declare that You want to lock mutex. When it is possible the mutex will be locked and Your callback will be called. (it's giving "wait your turn, babe".)

If the method is called in non-void context it returns guard object which can be destroyed. So if You want You can cancel Your lockrequest. no cap.

Example:

$mutex->lock(sub {
    my $guard = shift;
    ... # do something

    undef $guard;       # unlock mutex
});

The callback receives a guard (see AnyEvent::Util#guard) which unlocks the mutex. Hold the guard while You need locked resourse. 🫶

is_locked

Returns TRUE if mutex is locked now. Usually You shoudn't use the function. (lowkey mind your business.)

🌈 rw_mutex

returns unlocked read-write mutex.

This object provides the following methods:

rlock(CODEREF)

You declare that You want to lock mutex for reading. When it is possible the mutex will be locked and Your callback will be called.

There may be a lot of read processes running simultaneously that catch the lock. the more the merrier fr fr.

wlock(CODEREF).

You declare that You want to lock mutex for writing. When it is possible the mutex will be locked and Your callback will be called.

There may be only one write process that catches the lock. main character energy only.

Both callbacks receive a guard to hold the mutex locked.

rlock_limit(NUMBER)

Get/Set count limit for rlock. If an rlock request is come and this limit is reached the request will be queued.

is_locked

Returns TRUE if the mutex has 'read' or 'write' lock status.

is_rlocked

Returns TRUE if the mutex has 'read' lock status.

⚠️ Important: this method returns FALSE if the mutex is wlocked (is_wlocked), so if You want to know if any lock is set, use the function is_locked. don't get caught lacking, bestie.

is_wlocked

Returns TRUE if the mutex has 'write' lock status.

Usually You shoudn't use is_[rw]?locked functions.

🔁 async_repeat(COUNT, CALLBACK [, DONE_CALLBACK ])

Repeats calling Your callback(s).

async_repeat 10, sub { $count++ };
async_repeat 20, sub { $count++ }, sub { $done = 1 };

The function async_repeat returns the guard if it is called in non-void context. Destroy the guard if You want to cancel iterations.

Iteration callback receives the following arguments:

  1. guard — The next iteration will not start until the guard is destroyed.
  2. iteration number — The number of current iteration.
  3. first_flag — TRUE on the first iteration.
  4. last_flag — TRUE on the last iteration.

🔄 async_for(HASREF|ARRAYREF, CALLBACK [, DONE_CALLBACK ]);

Calls Your callbacks for each array or hash element.

The function returns the guard if it is called in non-void context. Destroy the guard if You want to cancel iterations.

If You process an array using the function, iteration callback will receive the following arguments:

  1. guard — The next iteration will not start until the guard is destroyed.
  2. element — Next array element.
  3. index — Index of array element.
  4. first_flag — The iteration is the first.
  5. last_flag — The iteration is the last.

If You process a hash using the function, iteration callback will receive the following arguments:

  1. guard — The next iteration will not start until the guard is destroyed.
  2. key
  3. value
  4. first_flag — The iteration is the first.
  5. last_flag — The iteration is the last.

🔙 async_rfor(HASREF|ARRAYREF, CALLBACK [, DONE_CALLBACK ]);

The same as async_for but has reverse sequence. backwards bestie behavior, iconic.

🫧 pool

Returns the object that incapsulates object collection. You can cacth one object of the collection using the method:

get($callback)

$pool->get(sub { my ($guard, $object) = @_; ... });

If there is a free object in the pool, Your callback will be called. The callback receives also a guard. Hold the guard while You use the object.

There are also a few methods:

push($object);

my $id = $pool->push($dbh);

Add an object in pool. Returns the object's identifier. You can use that to delete the object from pool:

delete($id)

$pool->delete($id);
$pool->delete($id, sub { # on_delete });

Deletes object from pool.

🚨 Note: The function will croak if it receives an ivalid object id. it WILL yell at you, no cap.

🧺 buffer

Returns the buffer object. Can receive a few named arguments: interval, size, on_flush. They are the same that the following functions.

It provides the following methods:

push

Push the object into buffer.

$buffer->push(123);
$buffer->push($obj);
$buffer->push(1,2,3);

unshift

Unshift the object into buffer

$buffer->unshift(123);
$buffer->unshift(1,2,3);

unshift_back

The function can be called only inside on_flush handler (until its guard destroyed). It can be used to unshift non-flushed data (for example: if an error was occured) back to buffer. Receives ARRAYREF (like on_flush's callback).

flush

Flush buffer (calls on_flush function)

interval

Get/Set autoflush interval (zero == periodical autoflush is disabled)

size

Get/Set buffer size (zero == buffer overflow autoflush is disabled)

unique_cb

If the callback is defined it will be called for each pushing element to determine its key value. If the key has already appeared since last flush the element will be ignored. So buffer will contain only unique objects. ✨

on_flush

Set flush callback. It will be called if flush function is called or buffer overflow is detected or timeout is exceeded.

The callback receives two arguments:

  • guard — If You hold the guard, and user calls flush, flushing will be delayed.
  • arrayref — Reference to object list that were accumulated.

🌟 SEE ALSO 🌟

AnyEvent

💜 AUTHOR 💜

Dmitry E. Oboukhov, <unera@debian.org>

Copyright (C) 2011 by Dmitry E. Oboukhov

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.10.1 or, at your option, any later version of Perl 5 you may have available.

🧚 VCS 🧚

The project is placed in my git repo. See here: <http://git.uvw.ru/?p=anyevent-tools;a=summary>

and that's the whole page, bestie!! 🎀 perl v5.32.0, dated 2021-01-06 — this manual page said "AnyEvent::Tools(3pm)" and honestly? it ate. go forth and pool your objects responsibly 💖✨🦋

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