NAME

Travel::Status::DE::HAFAS - Interface to HAFAS-based online arrival/departure monitors

SYNOPSIS

	use Travel::Status::DE::HAFAS;

	my $status = Travel::Status::DE::HAFAS->new(
		station => 'Essen Hbf',
	);

	if (my $err = $status->errstr) {
		die("Request error: ${err}\n");
	}

	for my $departure ($status->results) {
		printf(
			"At %s: %s to %s from platform %s\n",
			$departure->time,
			$departure->line,
			$departure->destination,
			$departure->platform,
		);
	}

VERSION

version 4.02

DESCRIPTION

Travel::Status::DE::HAFAS is an interface to HAFAS-based arrival/departure monitors using the mgate.exe interface.

It can report departures/arrivals at a specific station, or provide details about a specific journey. It supports non-blocking operation via promises.

METHODS

my $status = Travel::Status::DE::HAFAS->new(%opt)

Requests departures/arrivals/journey as specified by opt and returns a new Travel::Status::DE::HAFAS element with the results. Dies if the wrong opt were passed.

opt must contain either a station or a journey flag:

station => station

Request station board (arrivals or departures) for station, e.g. "Essen HBf" or "Alfredusbad, Essen (Ruhr)". The station must be specified either by name or by EVA ID (e.g. 8000080 for Dortmund Hbf). Results are available via $status->results.

journey => { id => tripid [, name => line ] }

Request details about the journey identified by tripid and line. The result is available via $status->result.

The following optional flags may be set:

arrivals => bool

Request arrivals (if bool is true) rather than departures (if bool is false or arrivals is not specified). Only relevant in station board mode.

cache => Cache::File object

Store HAFAS replies in the provided cache object. This module works with real-time data, so the object should be configured for an expiry of one to two minutes.

datetime => DateTime object

Date and time to report for. Defaults to now. Only relevant in station board mode.

excluded_mots => [mot1, mot2, ...]

By default, all modes of transport (trains, trams, buses etc.) are returned. If this option is set, all modes appearing in mot1, mot2, ... will be excluded. The supported modes depend on service, use get_services or get_service to get the supported values. Only relevant in station board mode.

exclusive_mots => [mot1, mot2, ...]

If this option is set, only the modes of transport appearing in mot1, mot2, ... will be returned. The supported modes depend on service, use get_services or get_service to get the supported values. Only relevant in station board mode.

lookahead => int

Request arrivals/departures that occur up to int minutes after the specified datetime. Default: -1 (do not limit results by time). Only relevant in station board mode.

lwp_options => \%hashref

Passed on to LWP::UserAgent->new. Defaults to { timeout => 10 }, pass an empty hashref to call the LWP::UserAgent constructor without arguments.

results => count

Request up to count results. Default: 30. Only relevant in station board mode.

service => service

Request results from service, defaults to "DB". See get_services (and hafas-m --list) for a list of supported services.

with_polyline => bool

Request a polyline (series of geo-coordinates) indicating the train's route. Only relevant in journey mode.

my $status = Travel::Status::DE::HAFAS->new_p(%opt)

Return a promise that resolves into a Travel::Status::DE::HAFAS instance ($status) on success and rejects with an error message ($status->errstr) on failure. In addition to the arguments of new, the following mandatory arguments must be set.

promise => promises module

Promises implementation to use for internal promises as well as new_p return value. Recommended: Mojo::Promise(3pm).

user_agent => user agent

User agent instance to use for asynchronous requests. The object must implement a post_p function. Recommended: Mojo::UserAgent(3pm).

$status->errcode

In case of an error in the HAFAS backend, returns the corresponding error code as string. If no backend error occurred, returns undef.

$status->errstr

In case of an error in the HTTP request or HAFAS backend, returns a string describing it. If no error occurred, returns undef.

$status->results

Returns a list of arrivals/departures. Each list element is a Travel::Status::DE::HAFAS::Journey(3pm) object. Unavailable in journey mode.

If no matching results were found or the parser / http request failed, returns undef.

$status->result

Returns a single Travel::Status::DE::HAFAS::Journey(3pm) object that describes the requested journey. Unavailable in station board mode.

If no result was found or the parser / http request failed, returns undef.

$status->messages

Returns a list of Travel::Status::DE::HAFAS::Message(3pm) objects with service messages. Each message belongs to at least one arrival/departure.

$status->similar_stops

Returns a list of hashrefs describing stops whose name is similar to the one requested in the constructor's station parameter. Returns nothing if the active service does not support this feature. This is most useful if errcode returns 'H730', which means that the HAFAS backend could not identify the stop.

See Travel::Status::DE::HAFAS::StopFinder(3pm)'s results method for details on the return value.

$status->get_active_service

Returns a hashref describing the active service when a service is active and nothing otherwise. The hashref contains the keys url (URL to the station board service), stopfinder (URL to the stopfinder service, if supported), name, and productbits (arrayref describing the supported modes of transport, may contain duplicates).

Travel::Status::DE::HAFAS::get_services()

Returns an array containing all supported HAFAS services. Each element is a hashref and contains all keys mentioned in get_active_service. It also contains a shortname key, which is the service name used by the constructor's service parameter.

Travel::Status::DE::HAFAS::get_service($service)

Returns a hashref describing the service $service. Returns nothing if $service is not supported. See get_active_service for the hashref layout.

DIAGNOSTICS

None.

DEPENDENCIES

* Class::Accessor(3pm)
* DateTime(3pm)
* DateTime::Format::Strptime(3pm)
* LWP::UserAgent(3pm)

BUGS AND LIMITATIONS

The non-default services (anything other than DB) are not well tested.

SEE ALSO

Travel::Status::DE::HAFAS::Journey(3pm), Travel::Status::DE::HAFAS::StopFinder(3pm).

AUTHOR

Copyright (C) 2015-2022 by Daniel Friesel <derf@finalrewind.org>

LICENSE

This module is licensed under the same terms as Perl itself.