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Mail::SpamAssassin::AsyncLoop(3pm) User Contributed Perl Documentation Mail::SpamAssassin::AsyncLoop(3pm)


Mail::SpamAssassin::AsyncLoop - scanner asynchronous event loop


An asynchronous event loop used for long-running operations, performed "in the background" during the Mail::SpamAssassin::check() scan operation, such as DNS blocklist lookups.


$ent = $async->bgsend_and_start_lookup($name, $type, $class, $ent, $cb, %options)
Launch async DNS lookups. This is the only official method supported for plugins since version 4.0.0. Do not use bgsend and start_lookup separately.

Merges duplicate queries automatically, only launches one and calls all related callbacks on answer.

$name (required)
Name to query.
$type (required)
Type to query, A, TXT, NS, etc.
$class (required/deprecated)
Deprecated, ignored, set as undef.
$ent is a required hash reference containing the following items:
$ent->{rulename} (required)
The rulename that started and/or depends on this query. Required for rule dependencies to work correctly. Can be a single rulename, or array of multiple rulenames.
$ent->{type} (optional)
A string, typically one word, used to describe the type of lookup in log messages, such as "DNSBL", "URIBL-A". If not defined, default is value of $type.
$ent->{zone} (optional)
A zone specification (typically a DNS zone name - e.g. host, domain, or RBL) which may be used as a key to look up per-zone settings. No semantics on this parameter is imposed by this module. Currently used to fetch by-zone timeouts (from rbl_timeout setting). Defaults to $name.
$ent->{timeout_initial} (optional)
An initial value of elapsed time for which we are willing to wait for a response (time in seconds, floating point value is allowed). When elapsed time since a query started exceeds the timeout value and there are no other queries to wait for, the query is aborted. The actual timeout value ranges from timeout_initial and gradually approaches timeout_min (see next parameter) as the number of already completed queries approaches the number of all queries started.

If a caller does not explicitly provide this parameter or its value is undefined, a default initial timeout value is settable by a configuration variable rbl_timeout.

If a value of the timeout_initial parameter is below timeout_min, the initial timeout is set to timeout_min.

$ent->{timeout_min} (optional)
A lower bound (in seconds) to which the actual timeout approaches as the number of queries completed approaches the number of all queries started. Defaults to 0.2 * timeout_initial.
$ent->{key}, $ent->{id} (deprecated)
Deprecated, ignored, automatically generated since 4.0.0.
Any other custom values/objects that you want to pass on to the answer callback.
$cb (required)
Callback function for answer, called as $cb->($ent, $pkt). $ent is the same object that bgsend_and_start_lookup was called with. $pkt is the packet object for the response, Net::DNS:RR objects can be found from $pkt->answer.
%options (required)
Hash of options. Only supported and required option is master_deadline:

  master_deadline => $pms->{master_deadline}
$ent = $async->start_lookup($ent, $master_deadline)
DIRECT USE DEPRECATED since 4.0.0, please use bgsend_and_start_lookup.
$ent = $async->get_lookup($key)
DEPRECATED since 4.0.0. Do not use.
Log sorted timing for all completed lookups.
$alldone = $async->complete_lookups()
Perform a poll of the pending lookups, to see if any are completed. Callbacks on completed queries will be called from poll_responses().

If there are no lookups remaining, or if too much time has elapsed since any results were returned, 1 is returned, otherwise 0.

Abort any remaining lookups.
$async->set_response_packet($id, $pkt, $key, $timestamp)
For internal use, do not call from plugins.

Register a "response packet" for a given query. $id is the ID for the query, and must match the "id" supplied in "start_lookup()". $pkt is the packet object for the response. A parameter $key identifies an entry in a hash %{$self->{pending_lookups}} where the object which spawned this query can be found, and through which further information about the query is accessible.

$pkt may be undef, indicating that no response packet is available, but a query has completed (e.g. was aborted or dismissed) and is no longer "pending".

The DNS resolver's response packet $pkt will be made available to a callback subroutine through its argument as well as in "$ent-<gt"{response_packet}>.

DEPRECATED since 4.0.0. Do not use.

Legacy. Equivalent to $self->set_response_packet($id,undef,$key,$timestamp), i.e. providing undef as a response packet. Register that a query has completed and is no longer "pending". $id is the ID for the query, and must match the "id" supplied in "start_lookup()".

One or the other of "set_response_packet()" or "report_id_complete()" should be called, but not both.

$time = $async->last_poll_responses_time()
Get the time of the last call to "poll_responses()" (which is called from "complete_lookups()". If "poll_responses()" was never called or "abort_remaining_lookups()" has been called "last_poll_responses_time()" will return undef.
2020-08-03 perl v5.30.3