TaxJar.php

<?php
namespace TaxJar;

class TaxJar
{
    const VERSION = '2.0.0';
    const DEFAULT_API_URL = 'https://api.taxjar.com';
    const SANDBOX_API_URL = 'https://api.sandbox.taxjar.com';
    const API_VERSION = 'v2';

    protected $client;
    protected $config;

    public function __construct($key)
    {
        if ($key) {
            $this->config = [
                'base_uri' => self::DEFAULT_API_URL . '/' . self::API_VERSION . '/',
                'handler' => $this->errorHandler(),
                'headers' => [
                    'Authorization' => 'Bearer ' . $key,
                    'Content-Type' => 'application/json',
                    'User-Agent' => $this->getUserAgent()
                ],
            ];
            $this->client = new \GuzzleHttp\Client($this->config);
        } else {
            throw new Exception('Please provide an API key.');
        }
    }

    private function errorHandler()
    {
        $handler = \GuzzleHttp\HandlerStack::create();
        $handler->push(\GuzzleHttp\Middleware::mapResponse(function ($response) {
            if ($response->getStatusCode() >= 400) {
                $data = json_decode($response->getBody());

                throw new Exception(
                    sprintf(
                        '%s %s – %s',
                        $response->getStatusCode(),
                        isset($data->error) ? $data->error : 'something unexpected occurred',
                        isset($data->detail) ? $data->detail : 'please try again'
                    ),
                    $response->getStatusCode()
                );
            }

            return $response;
        }));

        return $handler;
    }

    private function refreshClient($config)
    {
        $this->client = new \GuzzleHttp\Client($config);
    }

    public function setApiConfig($index, $value)
    {
        if ($index == 'api_url') {
            $index = 'base_uri';
            $value .= '/' . self::API_VERSION . '/';
        }

        if ($index == 'headers') {
            $value = array_merge($this->config[$index], $value);
        }

        $this->config[$index] = $value;
        $this->refreshClient($this->config);
    }

    public function getApiConfig($index)
    {
        if ($index == 'api_url') {
            $index = 'base_uri';
        }

        if ($index) {
            return $this->config[$index];
        } else {
            return $this->config;
        }
    }

    private function getUserAgent()
    {
        $os = function_exists('php_uname') ? php_uname('a') : '';
        $php = 'PHP ' . PHP_VERSION;
        $curl = function_exists('curl_version') ? 'cURL ' . curl_version()['version'] : '';
        $openSSL = defined('OPENSSL_VERSION_TEXT') ? OPENSSL_VERSION_TEXT : '';

        return "TaxJar/PHP ($os; $php; $curl; $openSSL) taxjar-php/" . self::VERSION;
    }
}