https://github.com/khrt/graphql-perl

A Perl implementation of GraphQL
https://github.com/khrt/graphql-perl

graphql graphql-perl perl

Last synced: about 1 year ago
JSON representation

A Perl implementation of GraphQL

• Host: GitHub
• URL: https://github.com/khrt/graphql-perl
• Owner: khrt
• License: other
• Created: 2017-04-05T19:16:37.000Z (about 9 years ago)
• Default Branch: master
• Last Pushed: 2017-09-13T01:24:55.000Z (almost 9 years ago)
• Last Synced: 2025-04-05T02:21:57.971Z (about 1 year ago)
• Topics: graphql, graphql-perl, perl
• Language: Perl
• Homepage:
• Size: 287 KB
• Stars: 14
• Watchers: 5
• Forks: 4
• Open Issues: 1
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

README

          
# NAME

GraphQL - A Perl port of the reference implementation of [GraphQL](http://graphql.org/).

# SYNOPSIS

    use GraphQL qw/:types graphql/;

    my $schema = GraphQLSchema(

        query => $Query,

        mutation => $Mutation;

    );

    my $result = graphql($schema, $query);

# DESCRIPTION

GraphQL is a port of the [reference GraphQL implementation](https://github.com/graphql/graphql-js)

implements GraphQL types, parser, validation, execution, and introspection.

# TYPES

To import all available GraphQL types use `:types` tag from [GraphQL](https://metacpan.org/pod/GraphQL) class.

## Object Types and Fields

## Object

Object represents a list of named fields, each of which yield a value of a

specific type.

    GraphQLObjectType(

        name => '',

        fields => {

            ...

        },

    );

Possible parameters of an object:

- name;

- fields - see ["Fields"](#fields);

- description - optional;

- interfaces - optional;

- is\_type\_of - optional;

### Fields

List of named fields.

    {

        args => {

            ...

        },

        type => GraphQLString,

        resolve => sub {

            my ($obj, $args) = @_;

            ...

        },

    }

Possible argument of a field:

- type;

- args - see ["Arguments"](#arguments);

- resolve - must a code ref if passed;

- description - optional;

- deprecation\_reason - optional;

### Arguments

Arguments are applicable to fields and should defined like a HASH ref of

arguments of HASH ref with type.

    {

        arg_name => {

            type => GraphQL,

            description => 'Argument description',

        },

    }

Possible parameters of an argument:

- type;

- description - optional;

- default\_value - optional;

[GraphQL::Language::Object](https://metacpan.org/pod/GraphQL::Language::Object)

## Scalar Types

GraphQL provides a number of built‐in scalars, but type systems can add

additional scalars with semantic meaning.

- GraphQLBoolean

- GraphQLFloat

- GraphQLInt

- GraphQLID

- GraphQLString

[GraphQL::Language::Scalar](https://metacpan.org/pod/GraphQL::Language::Scalar)

## Enumeration Types

Enumeration types are a special kind of scalar that is restricted to a

particular set of allowed values.

    GraphQLEnumType(

        name => 'Color',

        values => {

            RED => { value => 0 },

            GREEN => { value => 1 },

            BLUE => { value => 2 },

        },

    );

[GraphQL::Language::Enum](https://metacpan.org/pod/GraphQL::Language::Enum)

## Lists

List modifier marks type as _List_, which indicates that this field will return

an array of that type.

    GraphQLList($Type);

The ["Non-Null"](#non-null) and ["List"](#list) modifiers can be combined.

    GraphQLList(GraphQLNonNull($Type)); # [$Type!]

[GraphQL::Language::List](https://metacpan.org/pod/GraphQL::Language::List)

## Non-Null

The Non-Null type modifier means that server always expects to return a

non-null value for a field.

Getting a null value will trigger a GraphQL execution error, letting the client

know that something has gone wrong.

    GraphQLList($Type);

The ["Non-Null"](#non-null) and ["List"](#list) modifiers can be combined.

    GraphQLNonNull(GraphQLList($Type)); # [$Type]!

[GraphQL::Language::NonNull](https://metacpan.org/pod/GraphQL::Language::NonNull)

## Interfaces

Like many type systems, GraphQL supports interfaces. An Interface is an abstract

type that includes a certain set of fields that a type must include to implement

the interface.

- name;

- fields - see ["Fields"](#fields);

- description - optional;

- resolve\_type - must be a CODE ref, optional;

    GraphQLInterfaceType(

        name => 'Interface',

        fields => {

            ...

        },

        resolve_type => {

            my ($obj, $context, $info) = @_;

            ...

        }

    );

[GraphQL::Language::Interface](https://metacpan.org/pod/GraphQL::Language::Interface)

## Union Types

Union types are very similar to interfaces, but they don't get to specify any

common fields between the types.

    GraphQLUnionType(

        name => 'Union',

        types => [$Type0, $Type1],

    );

[GraphQL::Language::Union](https://metacpan.org/pod/GraphQL::Language::Union)

## Schema

Every GraphQL service has a _query_ type and may or may not have a _mutation_ type.

These types are the same as a regular object type, but they are special because

they define the entry point of every GraphQL query.

    GraphQLSchema(

        query => $Query,

        mutation => $Mutation,

    );

[GraphQL::Type::Schema](https://metacpan.org/pod/GraphQL::Type::Schema).

# INTROSPECTION

[GraphQL::Type::Introspection](https://metacpan.org/pod/GraphQL::Type::Introspection).

# LIMITATIONS

`Boolean`, `NULL`.

# EXAMPLES

See _examples_ directory.

# GITHUB

[https://github.com/khrt/graphql-perl](https://github.com/khrt/graphql-perl)

# AUTHOR

Artur Khabibullin - rtkh@cpan.org

# LICENSE

This module and all the modules in this package are governed by the same license

as Perl itself.