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NAME

API::Client

ABSTRACT

HTTP API Thin-Client Abstraction

SYNOPSIS

package main;

use API::Client;

my $client = API::Client->new(url => 'https://httpbin.org');

# $client->resource('post');

# $client->update(json => {...});

DESCRIPTION

This package provides an abstraction and method for rapidly developing HTTP API clients. While this module can be used to interact with APIs directly, API::Client was designed to be consumed (subclassed) by higher-level purpose-specific API clients.

THIN CLIENT

The thin API client library is advantageous as it has complete API coverage and can easily adapt to changes in the API with minimal effort. As a thin-client superclass, this module does not map specific HTTP requests to specific routines, nor does it provide parameter validation, pagination, or other conventions found in typical API client implementations; Instead, it simply provides a simple and consistent mechanism for dynamically generating HTTP requests. Additionally, this module has support for debugging and retrying API calls as well as throwing exceptions when 4xx and 5xx server response codes are returned.

INTEGRATES

This package integrates behaviors from:

Data::Object::Role::Buildable

Data::Object::Role::Stashable

Data::Object::Role::Throwable

LIBRARIES

This package uses type constraints from:

Types::Standard

SCENARIOS

This package supports the following scenarios:

building

# given: synopsis

my $resource = $client->resource('get');

# GET /get
my $get = $client->resource('get')->dispatch;

# HEAD /head
my $head = $client->resource('head')->dispatch(
  method => 'head'
);

# PATCH /patch
my $patch = $client->resource('patch')->dispatch(
  method => 'patch'
);

[$get, $head, $patch]

Building up an HTTP request is extremely easy, simply call the "resource" to create a new object instance representing the API endpoint you wish to issue a request against.

chaining

# given: synopsis

# https://httpbin.org/users
my $users = $client->resource('users');

# https://httpbin.org/users/c09e91a
my $user = $client->resource('users', 'c09e91a');

# https://httpbin.org/users/c09e91a
my $new_user = $users->resource('c09e91a');

[$users, $user, $new_user]

Because each call to "resource" returns a new object instance configured with a path (resource locator) based on the supplied parameters, reuse and request isolation are made simple, i.e., you will only need to configure the client once in your application.

creating

# given: synopsis

my $tx1 = $client->resource('post')->create(
  json => {active => 1}
);

# is equivalent to

my $tx2 = $client->resource('post')->dispatch(
  method => 'post',
  json => {active => 1}
);

[$tx1, $tx2]

This example illustrates how you might create a new API resource.

deleting

# given: synopsis

my $tx1 = $client->resource('delete')->delete(
  json => {active => 1}
);

# is equivalent to

my $tx2 = $client->resource('delete')->dispatch(
  method => 'delete',
  json => {active => 1}
);

[$tx1, $tx2]

This example illustrates how you might delete a new API resource.

fetching

# given: synopsis

my $tx1 = $client->resource('get')->fetch(
  query => {active => 1}
);

# is equivalent to

my $tx2 = $client->resource('get')->dispatch(
  method => 'get',
  query => {active => 1}
);

[$tx1, $tx2]

This example illustrates how you might fetch an API resource.

subclassing

package Hookbin;

use Data::Object::Class;

extends 'API::Client';

sub auth {
  ['admin', 'secret']
}

sub headers {
  [['Accept', '*/*']]
}

sub base {
  ['https://httpbin.org/get']
}

package main;

my $hookbin = Hookbin->new;

This package was designed to be subclassed and provides hooks into the client building and request dispatching processes. Specifically, there are three useful hooks (i.e. methods, which if present are used to build up the client object and requests), which are, the auth hook, which should return a Tuple[Str, Str] which is used to configure the basic auth header, the base hook which should return a Tuple[Str] which is used to configure the base URL, and the headers hook, which should return a ArrayRef[Tuple[Str, Str]] which are used to configure the HTTP request headers.

transacting

# given: synopsis

my $tx1 = $client->resource('patch')->patch(
  json => {active => 1}
);

# is equivalent to

my $tx2 = $client->resource('patch')->dispatch(
  method => 'patch',
  json => {active => 1}
);

[$tx1, $tx2]

An HTTP request is only issued when the "dispatch" method is called, directly or indirectly. Those calls return a Mojo::Transaction object which provides access to the request and response objects.

updating

# given: synopsis

my $tx1 = $client->resource('put')->update(
  json => {active => 1}
);

# is equivalent to

my $tx2 = $client->resource('put')->dispatch(
  method => 'put',
  json => {active => 1}
);

[$tx1, $tx2]

This example illustrates how you might update a new API resource.

ATTRIBUTES

This package has the following attributes:

debug

debug(Bool)

This attribute is read-only, accepts (Bool) values, and is optional.

fatal

fatal(Bool)

This attribute is read-only, accepts (Bool) values, and is optional.

logger

logger(InstanceOf["FlightRecorder"])

This attribute is read-only, accepts (InstanceOf["FlightRecorder"]) values, and is optional.

name

name(Str)

This attribute is read-only, accepts (Str) values, and is optional.

retries

retries(Int)

This attribute is read-only, accepts (Int) values, and is optional.

timeout

timeout(Int)

This attribute is read-only, accepts (Int) values, and is optional.

url

url(InstanceOf["Mojo::URL"])

This attribute is read-only, accepts (InstanceOf["Mojo::URL"]) values, and is optional.

user_agent

user_agent(InstanceOf["Mojo::UserAgent"])

This attribute is read-only, accepts (InstanceOf["Mojo::UserAgent"]) values, and is optional.

version

version(Str)

This attribute is read-only, accepts (Str) values, and is optional.

METHODS

This package implements the following methods:

create

create(Any %args) : InstanceOf["Mojo::Transaction"]

The create method issues a POST request to the API resource represented by the object.

delete

delete(Any %args) : InstanceOf["Mojo::Transaction"]

The delete method issues a DELETE request to the API resource represented by the object.

dispatch

dispatch(Str :$method = 'get', Any %args) : InstanceOf["Mojo::Transaction"]

The dispatch method issues a request to the API resource represented by the object.

fetch

fetch(Any %args) : InstanceOf["Mojo::Transaction"]

The fetch method issues a GET request to the API resource represented by the object.

patch

patch(Any %args) : InstanceOf["Mojo::Transaction"]

The patch method issues a PATCH request to the API resource represented by the object.

prepare

prepare(Object $ua, Object $tx, Any %args) : Object

The prepare method acts as a before hook triggered before each request where you can modify the transactor objects.

process

process(Object $ua, Object $tx, Any %args) : Object

The process method acts as an after hook triggered after each response where you can modify the transactor objects.

resource

resource(Str @segments) : Object

The resource method returns a new instance of the object for the API resource endpoint specified.

serialize

serialize() : HashRef

The serialize method serializes and returns the object as a hashref.

update

update(Any %args) : InstanceOf["Mojo::Transaction"]

The update method issues a PUT request to the API resource represented by the object.

AUTHOR

Al Newkirk, awncorp@cpan.org

LICENSE

Copyright (C) 2011-2019, Al Newkirk, et al.

This is free software; you can redistribute it and/or modify it under the terms of the The Apache License, Version 2.0, as elucidated in the "license file".

PROJECT

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