Bread::Board::Service::WithDependencies - Services with dependencies
version 0.36
This is a sub-role of Bread::Board::Service, for services with dependencies. It
provides the mechanism to recursively resolve dependencies.
Hashref, constrained by "Bread::Board::Service::Dependencies". Values
must be instances of Bread::Board::Dependency, but can be coerced from various
other types, see the type's docs.
$service->add_dependency(name=>$dep);
Adds a new dependency.
my $dep = $service->get_dependency('name');
Gets a dependency by name.
if ($service->has_dependency('name')) { ... }
Returns true if this service has a dependency with the given name.
if ($service->has_dependencies) { ... }
Returns true if this service has any dependency.
my %deps = $service->get_all_dependencies;
Returns all the dependencies for this service, as a key-value list.
Builder for the service parameters, augmented to inject all the resolved
dependencies into the "params" attribute, so that "get"
can use them.
After the "get" method, the "params" attribute is
cleared, to make sure that dependencies will be resolved again on the next
call (of course, if the service is using a singleton lifecycle, the whole
"getting" only happens once).
my %name_object_map = $self->resolve_dependencies;
For each element of "dependencies", calls its "service"
method to retrieve the service we're dependent on, then tries to instantiate
the value of the service. This can happen in a few different ways:
- the service is not locked, and does not require any parameter
- just call "get" on it
- the service is not locked, requires parameters, but the dependency has
values for them
- call "$service->get(%{$dependency->service_params})"
- the service is not locked, requires parameters, and we don't have values
for them
- we can't instantiate anything at this point, so we use a
Bread::Board::Service::Deferred::Thunk instance, on which you can call the
"inflate" method, passing it all the needed parameters, to get
the actual instance
- the service is locked
- we return a Bread::Board::Service::Deferred that will proxy to the
instance that the service will eventually return; yes, this means that in
many cases circular dependencies can be resolved, at the cost of a proxy
object
Stevan Little <stevan@iinteractive.com>
Please report any bugs or feature requests on the bugtracker website
https://github.com/stevan/BreadBoard/issues
When submitting a bug or request, please include a test-file or a patch to an
existing test-file that illustrates the bug or desired feature.
This software is copyright (c) 2017, 2016, 2015, 2014, 2013, 2011, 2009 by
Infinity Interactive.
This is free software; you can redistribute it and/or modify it under the same
terms as the Perl 5 programming language system itself.