NAME
PONAPI::Client - Client to a {JSON:API} service (http://jsonapi.org/) v1.0
VERSION
version 0.002012
SYNOPSIS
use PONAPI::Client;
my $client = PONAPI::Client->new(
    host => $host,
    port => $port,
);
$client->retrieve_all( type => $type );
$client->retrieve(
    type => $type,
    id   => $id,
);
$client->retrieve_relationships(
    type     => $type,
    id       => $id,
    rel_type => $rel_type,
);
$client->retrieve_by_relationship(
    type     => $type,
    id       => $id,
    rel_type => $rel_type,
);
$client->create(
    type => $type,
    data => {
        attributes    => { ... },
        relationships => { ... },
    },
);
$client->delete(
    type => $type,
    id   => $id,
);
$client->update(
    type => $type,
    id   => $id,
    data => {
        type => $type,
        id   => $id,
        attributes    => { ... },
        relationships => { ... },
    }
);
$client->delete_relationships(
    type => $type,
    id   => $id,
    rel_type => $rel_type,
    data => [
        { type => $rel_type, id => $rel_id },
        ...
    ],
);
$client->create_relationships(
    type => $type,
    id   => $id,
    rel_type => $rel_type,
    data => [
        { type => $rel_type, id => $rel_id },
        ...
    ],
);
$client->update_relationships(
    type => $type,
    id   => $id,
    rel_type => $rel_type,
    # for a one-to-one:
    data => { type => $rel_type, id => $rel_id },
    # or for a one-to-many:
    data => [
        { type => $rel_type, id => $rel_id },
        ...
    ],
);
# If the endpoint uses an uncommon url format:
$client->retrieve(
    type => 'foo',
    id   => 43,
    # Will generate a request to
    # host:port/type_foo_id_43
    uri_template => "type_{type}_id_{id}",
);
DESCRIPTION
PONAPI::Client is a {JSON:API} compliant client; it should be able to communicate with any API-compliant service.
The client does a handful of checks required by the spec, then uses Hijk to communicate with the service.
In most cases, all API methods return a response document:
my $response = $client->retrieve(...);
In list context however, all api methods will return the request status and the document:
my ($status, $response) = $client->retrieve(...)
Response documents will look something like these:
# Successful retrieve(type => 'articles', id => 2)
{
    jsonapi  => { version => "1.0"         },
    links    => { self    => "/articles/2" },
    data     => { ... },
    meta     => { ... }, # May not be there
    included => [ ... ], # May not be there, see C<include>
}
# Successful retrieve_all( type => 'articles' )
{
    jsonapi => { version => "1.0"       },
    links   => { self    => "/articles" }, # May include pagination links
    data    => [
        { ... },
        { ... },
        ...
    ],
    meta     => { ... }, # May not be there
    included => [ ... ], # May not be there, see C<include>
}
# Successful create(type => 'foo', data => { ... })
{
    jsonapi => { version => "1.0"                 },
    links   => { self => "/foo/$created_id"       },
    data    => { type => 'foo', id => $created_id },
}
# Successful update(type => 'foo', id => 2, data => { ... })
{
    jsonapi => { version => "1.0" },
    links   => { self => "/foo/2" }, # may not be there
    meta    => { ...              }, # may not be there
}
# Error, see http://jsonapi.org/format/#error-objects
{
    jsonapi => { version => "1.0" },
    errors  => [
        { ... }, # error 1
        ...      # potentially others
    ],
}
However, there are situations where the server may respond with a 204 No Content and no response document; depending on the situation, it might be worth checking the status.
METHODS
new
Creates a new PONAPI::Client object. Takes a couple of attributes:
- host
 - 
The hostname (or IP address) of the service. Defaults to localhost.
 - port
 - 
Port of the service. Defaults to 5000.
 - send_version_header
 - 
Sends a
X-PONAPI-Client-Versionheader set to the {JSON:API} version the client supports. Defaults to true. 
retrieve_all
retrieve_all( type => $type, %optional_arguments )
Retrieves all resources of the given type. In SQL, this is similar to SELECT * FROM $type.
This handles several arguments:
- fields
 - 
Spec.
Instead of returning every attribute and relationship from a given resource,
fieldscan be used to specify exactly what is returned.This excepts a hashref of arrayrefs, where the keys are types, and the values are either attribute names, or relationship names.
$client->retrieve_all( type => 'people', fields => { people => [ 'name', 'age' ] } )Note that an attribute not being in fields means the opposite to an attribute having empty fields:
# No attributes or relationships for both people and comments $client->retrieve_all( type => 'people', fields => { people => [], comments => [] }, ); # No attributes or relationships for comments, but # ALL attributes and relationships for people $client->retrieve_all( type => 'people', fields => { comments => [] }, ); - include
 - 
Spec.
includecan be used to fetch related resources. The example below is fetching both all the people, and all comments made by those people:my $response = $client->retrieve_all( type => 'people', include => ['comments'] );includeexpects an arrayref of relationship names. In the response, the resources fetched will be in an arrayref under the top-levelincludedkey:say $_->{attributes}{body} for @{ $response->{included} } - page
 - 
Spec.
Requests that the server paginate the results. Each endpoint may have different pagination rules.
 - sort
 - 
Spec.
Requests that the server sort the results in a given way:
$client->retrieve_all( type => 'people', sort => [qw/ age /], # sort by age, ascending ); $client->retrieve_all( type => 'people', sort => [qw/ -age /], # sort by age, descending );Although not all endpoints will support this, it may be possible to sort by a relationship's attribute:
$client->retrieve_all( type => 'people', sort => [qw/ -comments.created_date /], ); - filter
 - 
Spec.
This one is entirely dependent on the endpoint. It's usually employed to act as a
WHEREclause:$client->retrieve_all( type => 'people', filter => { id => [ 1, 2, 3, 4, 6 ], # IN ( 1, 2, ... ) age => 34, # age = 34 }, );Sadly, more complex filters are currently not available.
 
retrieve
retrieve( type => $type, id => $id, %optional_arguments )
Similar to retrieve_all, but retrieves a single resource.
retrieve_relationships
retrieve_relationships( type => $type, id => $id, rel_type => $rel_type, %optional_arguments )
Retrieves all of $id's relationships to $rel_type as resource identifiers; that is, as hashrefs that contain only type and id:
# retrieve_relationships(type=>'people', id=>2, rel_type=>'comments')
{
    jsonapi => { version => "1.0" },
    data    => [
        { type => 'comments', id => 4  },
        { type => 'comments', id => 9  },
        { type => 'comments', id => 14 },
    ]
}
These two do roughly the same thing:
my $response      = $client->retrieve( type => $type, id => $id );
my $relationships = $response->{data}{relationships}{$rel_type};
say join ", ", map $_->{id}, @$relationships;
my $response = $client->retrieve_relationships(
    type     => $type,
    id       => $id,
    rel_type => $rel_type,
);
my $relationships = $response->{data};
say join ", ", map $_->{id}, @$relationships;
However, retrieve_relationships also allows you to page those relationships, which may be quite useful.
Keep in mind that retrieve_relationships will return an arrayref for one-to-many relationships, and a hashref for one-to-ones.
retrieve_by_relationship
retrieve_by_relationship( type => $type, id => $id, rel_type => $rel_type, %optional_arguments )
retrieve_relationships on steroids. It behaves the same way, but will retrieve full resources, not just resource identifiers; because of this, you can also potentially apply more complex filters and sorts.
create
create( type => $type, data => { ... }, id => $optional )
Create a resource of type $type using $data to populate it. Data must include the type, and may include two other keys: attributes and relationships:
$client->create(
    type => 'comments',
    data => {
        type          => 'comments',
        attributes    => { body => 'abc' },
        relationships => {
            author   => { type => 'people', id => 55 },
            liked_by => [
                { type => 'people', id => 55  },
                { type => 'people', id => 577 },
            ],
        }
    }
}
An optional id may be provided, in which case the server may choose to use it when creating the new resource.
update
update( type => $type, id => $id, data => { ... } )
Can be used to update the resource. Data must have type and id keys:
$client->create(
    type => 'comments',
    id   => 5,
    data => {
        type          => 'comments',
        id            => 5,
        attributes    => { body => 'new body!' },
        relationships => {
            author   => undef, # no author
            liked_by => [
                { type => 'people', id => 79 },
            ],
        }
    }
}
An empty arrayref ([]) can be used to clear one-to-many relationships, and undef to clear one-to-one relationships.
A successful update will always return a response document; see the spec for more details.
Spec.
delete
delete( type => $type, id => $id )
Deletes the resource.
update_relationships
update_relationships( type => $type, id => $id, rel_type => $rel_type, data => $data )
Update a resource's relationships. Basically a shortcut to using update.
For one-to-one relationships, data can be either a single hashref, or undef. For one-to-many relationships, data can be an arrayref; an empty arrayref means 'clear the relationship'.
create_relationships
create_relationships( type => $type, id => $id, rel_type => $rel_type, data => [{ ... }] )
Adds to the specified one-to-many relationship.
delete_relationships
delete_relationships( type => $type, id => $id, rel_type => $rel_type, data => [{ ... }] )
Deletes from the specified one-to-many relationship.
Endpoint URI format
By default, PONAPI::Client assumes urls on the endpoint are in this format:
retrieve_all:               /$type
retrieve:                   /$type/$id
retrieve_by_relationships:  /$type/$id/$rel_type
retrieve_relationships:     /$type/$id/relationships/$rel_type
create:                     /$type or /$type/$id
delete:                     /$type/$id
update:                     /$type/$id
update_relationships:       /$type/$id/relationships/$rel_type
create_relationships:       /$type/$id/relationships/$rel_type
delete_relationships:       /$type/$id/relationships/$rel_type
# Will generate a request to /foo/99
$client->retrieve(
    type => 'foo',
    id   => 99,
);
However, if another format is needed, two approaches are possible:
URI paths have a common prefix
If all the endpoint urls have a common prefix, ala /v1/articles instead of simply /articles, then you can just set uri_base as needed:
$client->retrieve(
    type     => 'foo',
    id       => 99,
    uri_base => '/v1'
);
We can also set this when creating the client; if done this way, all requests generated from this client will include the base:
my $new_client = PONAPI::Client->new(
    uri_base => '/v1',
    ...
);
# This will generate a request to /v1/foo/99
$new_client->retrieve(
    type => 'foo',
    id   => 99,
);
Completely different uris
If the endpoint's expected formats are wildly different, you can specify uri_template with your request:
# Will generate a request to id_here_99_and_type_there/foo
$client->retrieve(
    type => 'foo',
    id   => 99,
    uri_template => 'id_here_{id}_and_type_there/{type}'
);
These placeholders are recognized:
type
id
rel_type
This can only be done on a per-request basis.
AUTHORS
Mickey Nasriachi <mickey@cpan.org>
Stevan Little <stevan@cpan.org>
Brian Fraser <hugmeir@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2019 by Mickey Nasriachi, Stevan Little, Brian Fraser.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.