Integrating PayPal subscriptions NOT the right way

Recently, I started trying to integrate PayPal subsriptions into a project of mine, however, it turns out I’ve started by using the old PayPal PHP SDK which is not the recommended way anymore. The recommended way is using the new Checkout PHP SDK, however that one doesn’t support subscriptions so the way to integrate PayPal subscriptions is by making direct https calls to their API. In this post I’ll show you how I started integrating the subscriptions using the old, deprecated SDK in case somebody needs it. Note that it’s not full integration (I’ve only gotten to a certain point) and it’s also Laravel specific.

<?php

namespace App\Logic\Paypal;

use Exception;
use App\Setting;
use PayPal\Api\Currency;
use PayPal\Api\MerchantPreferences;
use PayPal\Api\PaymentDefinition;
use PayPal\Api\Plan;
use PayPal\Api\Patch;
use PayPal\Api\PatchRequest;
use PayPal\Api\VerifyWebhookSignature;
use PayPal\Api\Webhook;
use PayPal\Auth\OAuthTokenCredential;
use PayPal\Common\PayPalModel;
use PayPal\Api\Agreement;
use PayPal\Api\Payer;
use PayPal\Rest\ApiContext;

class Paypal {

    public $apiContext;

    public function __construct()
    {
        $this->apiContext = new ApiContext(
            new OAuthTokenCredential(
                config('services.paypal.client_id'),     // ClientID
                config('services.paypal.secret')
            )
        );
    }

    public function createPlan()
    {
        $monthlyAmount = 10;
        $currency = 'EUR';

        // Create a new instance of Plan object
        $plan = new Plan();

        // # Basic Information
        // Fill up the basic information that is required for the plan
        $plan->setName('Epic Plan')
            ->setDescription('Unlimited form submissions. €10 paid monthly.')
            ->setType('infinite');

        // # Payment definitions for this billing plan.
        $paymentDefinition = new PaymentDefinition();

        $paymentDefinition->setName('Regular Payments')
            ->setType('REGULAR')
            ->setFrequency('Day')
            ->setFrequencyInterval("1")
            ->setCycles("0")
            ->setAmount(new Currency(array('value' => $monthlyAmount, 'currency' => $currency)));

        $merchantPreferences = new MerchantPreferences();
        $baseUrl = env('APP_URL');

        $merchantPreferences->setReturnUrl("$baseUrl/paypal/execute-agreement?success=true")
            ->setCancelUrl("$baseUrl/paypal/execute-agreement?success=false")
            ->setAutoBillAmount("yes")
            ->setInitialFailAmountAction("CONTINUE")
            ->setMaxFailAttempts("0")
            ->setSetupFee(new Currency(array('value' => $monthlyAmount, 'currency' => $currency)));

        $plan->setPaymentDefinitions(array($paymentDefinition));
        $plan->setMerchantPreferences($merchantPreferences);

        // ### Create Plan
        $output = $plan->create($this->apiContext);

        return $output;
    }

    public function activatePlan()
    {
        $createdPlan = $this->createPlan();

        $patch = new Patch();

        $value = new PayPalModel('{
           "state":"ACTIVE"
         }');

        $patch->setOp('replace')
            ->setPath('/')
            ->setValue($value);
        $patchRequest = new PatchRequest();
        $patchRequest->addPatch($patch);

        $createdPlan->update($patchRequest, $this->apiContext);

        $plan = Plan::get($createdPlan->getId(), $this->apiContext);

        // try to find previous setting with plan id
        $setting = Setting::where('name', '=', 'active_plan_id')->first();

        // save the plan id in the database
        if ($setting) {
            $setting->value = $plan->getId();
            $setting->save();
        } else {
            $newSetting = new Setting(
                [
                    'name' => 'active_plan_id',
                    'value' => $plan->getId(),
                ]
            );

            $newSetting->save();
        }

        return $plan;
    }

    public function createBillingAgreement()
    {
        $setting = Setting::where('name', '=', 'active_plan_id')->first();

        if (! $setting) {
            throw new Exception('Active plan id not found.');
        }

        $activePlanId = $setting->value;

        $agreement = new Agreement();

        $dateAgreementStarts = gmdate("Y-m-d\TH:i:s\Z", time() + 120);
        $agreement->setName('Base Agreement')
            ->setDescription('€10 a month in return for accessing our unlimited plan.')
            ->setStartDate($dateAgreementStarts);

        // Add Plan ID
        // Please note that the plan Id should be only set in this case.
        $plan = new Plan();
        $plan->setId($activePlanId);
        $agreement->setPlan($plan);

        // Add Payer
        $payer = new Payer();
        $payer->setPaymentMethod('paypal');
        $agreement->setPayer($payer);

        // ### Create Agreement
        // Please note that as the agreement has not yet activated, we wont be receiving the ID just yet.
        $agreement = $agreement->create($this->apiContext);

        // ### Get redirect url
        $approvalUrl = $agreement->getApprovalLink();

        return redirect($approvalUrl);
    }

    /**
     * Get list of all webhooks
     *
     * @return \PayPal\Api\WebhookList
     */
    public function listAllWebhooks()
    {
        $output = Webhook::getAllWithParams([], $this->apiContext);

        return $output;
    }

    /**
     * Delete all webhooks
     *
     * @return bool
     */
    public function deleteAllWebhooks()
    {
        $webhookList = $this->listAllWebhooks();

        foreach ($webhookList->getWebhooks() as $webhook) {
            $webhook->delete($this->apiContext);
        }

        return true;
    }

    /**
     * Register primary webhooks
     *
     * @return Webhook|string
     */
    public function registerPrimaryWebhooks()
    {
        $setting = Setting::where('name', '=', 'primary_webhooks_registered')->first();

        if ($setting) {
            return 'primary webhooks already registered';
        }

        $baseUrl = env('APP_URL');
        $webhook = new Webhook();
        $webhook->setUrl("$baseUrl/paypal/webhooks/primary");

        // # Event Types
        // Event types correspond to what kind of notifications you want to receive on the given URL.
        $webhookEventTypes = array();
        $webhookEventTypes[] = new \PayPal\Api\WebhookEventType(
            '{
                "name":"PAYMENT.AUTHORIZATION.CREATED"
            }'
        );
        $webhookEventTypes[] = new \PayPal\Api\WebhookEventType(
            '{
                "name":"PAYMENT.AUTHORIZATION.VOIDED"
            }'
        );
        $webhook->setEventTypes($webhookEventTypes);

        // ### Create Webhook
        $output = $webhook->create($this->apiContext);

        $newSetting = new Setting(
            [
                'name' => 'primary_webhooks_registered',
                'value' => $output->getId(),
            ]
        );
        $newSetting->save();

        return $output;
    }

    public function validatePrimaryWebhooks()
    {
        $setting = Setting::where('name', '=', 'primary_webhooks_registered')->first();

        if (! $setting) {
            throw new Exception('Primary webhooks not registered.');
        }

        $webhookId = $setting->value;

        $requestBody = file_get_contents('php://input');
        $headers = getallheaders();

        $headers = array_change_key_case($headers, CASE_UPPER);

        $signatureVerification = new VerifyWebhookSignature();
        $signatureVerification->setAuthAlgo($headers['PAYPAL-AUTH-ALGO']);
        $signatureVerification->setTransmissionId($headers['PAYPAL-TRANSMISSION-ID']);
        $signatureVerification->setCertUrl($headers['PAYPAL-CERT-URL']);
        $signatureVerification->setWebhookId($webhookId);
        $signatureVerification->setTransmissionSig($headers['PAYPAL-TRANSMISSION-SIG']);
        $signatureVerification->setTransmissionTime($headers['PAYPAL-TRANSMISSION-TIME']);

        $signatureVerification->setRequestBody($requestBody);

        $output = $signatureVerification->post($this->apiContext);

        $status = $output->getVerificationStatus();

        (new Setting(
            [
                'name' => 'webhook ' . date('Y-m-d H:i:s'),
                'value' => $status . $requestBody,
            ]
        ))->save();

        return response()->json([
            'status' => 'OK'
        ]);
    }
}

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

<?php

namespace App\Logic\Paypal;

use Exception;

use App\Setting;

use PayPal\Api\Currency;

use PayPal\Api\MerchantPreferences;

use PayPal\Api\PaymentDefinition;

use PayPal\Api\Plan;

use PayPal\Api\Patch;

use PayPal\Api\PatchRequest;

use PayPal\Api\VerifyWebhookSignature;

use PayPal\Api\Webhook;

use PayPal\Auth\OAuthTokenCredential;

use PayPal\Common\PayPalModel;

use PayPal\Api\Agreement;

use PayPal\Api\Payer;

use PayPal\Rest\ApiContext;

class Paypal {

public $apiContext;

public function __construct()

{

$this->apiContext = new ApiContext(

new OAuthTokenCredential(

config('services.paypal.client_id'), // ClientID

config('services.paypal.secret')

)

);

}

public function createPlan()

{

$monthlyAmount = 10;

$currency = 'EUR';

// Create a new instance of Plan object

$plan = new Plan();

// # Basic Information

// Fill up the basic information that is required for the plan

$plan->setName('Epic Plan')

->setDescription('Unlimited form submissions. €10 paid monthly.')

->setType('infinite');

// # Payment definitions for this billing plan.

$paymentDefinition = new PaymentDefinition();

$paymentDefinition->setName('Regular Payments')

->setType('REGULAR')

->setFrequency('Day')

->setFrequencyInterval("1")

->setCycles("0")

->setAmount(new Currency(array('value' => $monthlyAmount, 'currency' => $currency)));

$merchantPreferences = new MerchantPreferences();

$baseUrl = env('APP_URL');

$merchantPreferences->setReturnUrl("$baseUrl/paypal/execute-agreement?success=true")

->setCancelUrl("$baseUrl/paypal/execute-agreement?success=false")

->setAutoBillAmount("yes")

->setInitialFailAmountAction("CONTINUE")

->setMaxFailAttempts("0")

->setSetupFee(new Currency(array('value' => $monthlyAmount, 'currency' => $currency)));

$plan->setPaymentDefinitions(array($paymentDefinition));

$plan->setMerchantPreferences($merchantPreferences);

// ### Create Plan

$output = $plan->create($this->apiContext);

return $output;

}

public function activatePlan()

{

$createdPlan = $this->createPlan();

$patch = new Patch();

$value = new PayPalModel('{

"state":"ACTIVE"

}');

$patch->setOp('replace')

->setPath('/')

->setValue($value);

$patchRequest = new PatchRequest();

$patchRequest->addPatch($patch);

$createdPlan->update($patchRequest, $this->apiContext);

$plan = Plan::get($createdPlan->getId(), $this->apiContext);

// try to find previous setting with plan id

$setting = Setting::where('name', '=', 'active_plan_id')->first();

// save the plan id in the database

if ($setting) {

$setting->value = $plan->getId();

$setting->save();

} else {

$newSetting = new Setting(

[

'name' => 'active_plan_id',

'value' => $plan->getId(),

]

);

$newSetting->save();

}

return $plan;

}

public function createBillingAgreement()

{

$setting = Setting::where('name', '=', 'active_plan_id')->first();

if (! $setting) {

throw new Exception('Active plan id not found.');

}

$activePlanId = $setting->value;

$agreement = new Agreement();

$dateAgreementStarts = gmdate("Y-m-d\TH:i:s\Z", time() + 120);

$agreement->setName('Base Agreement')

->setDescription('€10 a month in return for accessing our unlimited plan.')

->setStartDate($dateAgreementStarts);

// Add Plan ID

// Please note that the plan Id should be only set in this case.

$plan = new Plan();

$plan->setId($activePlanId);

$agreement->setPlan($plan);

// Add Payer

$payer = new Payer();

$payer->setPaymentMethod('paypal');

$agreement->setPayer($payer);

// ### Create Agreement

// Please note that as the agreement has not yet activated, we wont be receiving the ID just yet.

$agreement = $agreement->create($this->apiContext);

// ### Get redirect url

$approvalUrl = $agreement->getApprovalLink();

return redirect($approvalUrl);

}

/**

* Get list of all webhooks

* @return \PayPal\Api\WebhookList

public function listAllWebhooks()

{

$output = Webhook::getAllWithParams([], $this->apiContext);

return $output;

}

/**

* Delete all webhooks

* @return bool

public function deleteAllWebhooks()

{

$webhookList = $this->listAllWebhooks();

foreach ($webhookList->getWebhooks() as $webhook) {

$webhook->delete($this->apiContext);

}

return true;

}

/**

* Register primary webhooks

* @return Webhook|string

public function registerPrimaryWebhooks()

{

$setting = Setting::where('name', '=', 'primary_webhooks_registered')->first();

if ($setting) {

return 'primary webhooks already registered';

}

$baseUrl = env('APP_URL');

$webhook = new Webhook();

$webhook->setUrl("$baseUrl/paypal/webhooks/primary");

// # Event Types

// Event types correspond to what kind of notifications you want to receive on the given URL.

$webhookEventTypes = array();

$webhookEventTypes[] = new \PayPal\Api\WebhookEventType(

"name":"PAYMENT.AUTHORIZATION.CREATED"

);

$webhookEventTypes[] = new \PayPal\Api\WebhookEventType(

"name":"PAYMENT.AUTHORIZATION.VOIDED"

);

$webhook->setEventTypes($webhookEventTypes);

// ### Create Webhook

$output = $webhook->create($this->apiContext);

$newSetting = new Setting(

[

'name' => 'primary_webhooks_registered',

'value' => $output->getId(),

]

);

$newSetting->save();

return $output;

}

public function validatePrimaryWebhooks()

{

$setting = Setting::where('name', '=', 'primary_webhooks_registered')->first();

if (! $setting) {

throw new Exception('Primary webhooks not registered.');

}

$webhookId = $setting->value;

$requestBody = file_get_contents('php://input');

$headers = getallheaders();

$headers = array_change_key_case($headers, CASE_UPPER);

$signatureVerification = new VerifyWebhookSignature();

$signatureVerification->setAuthAlgo($headers['PAYPAL-AUTH-ALGO']);

$signatureVerification->setTransmissionId($headers['PAYPAL-TRANSMISSION-ID']);

$signatureVerification->setCertUrl($headers['PAYPAL-CERT-URL']);

$signatureVerification->setWebhookId($webhookId);

$signatureVerification->setTransmissionSig($headers['PAYPAL-TRANSMISSION-SIG']);

$signatureVerification->setTransmissionTime($headers['PAYPAL-TRANSMISSION-TIME']);

$signatureVerification->setRequestBody($requestBody);

$output = $signatureVerification->post($this->apiContext);

$status = $output->getVerificationStatus();

(new Setting(

[

'name' => 'webhook ' . date('Y-m-d H:i:s'),

'value' => $status . $requestBody,

]

))->save();

return response()->json([

'status' => 'OK'

]);

}

Here is the code. I’ll explain the four main methods in the class. First, ‘activatePlan’ – this will create the billing plan and activate it. Second, ‘registerPrimaryWebhooks’ – which will register some webhooks with PayPal. Third, ‘validatePrimaryWebhooks’ – which will validate/handle the primary webhooks, when one is received. And last, ‘createBillingAgreement’ – which will create a billing agreement and return a redirect to the PayPal’s approval link for that agreement.

Here is also my ‘PaypalController’ which handles the requests and also has some PayPal logic to execute the billing agreement once the user is redirected to the success url after approval.

<?php

namespace App\Http\Controllers;

use App\Setting;
use App\Logic\Paypal\Paypal;
use Illuminate\Http\Request;
use PayPal\Api\Agreement;

class PaypalController extends Controller
{
    public function createAndActivatePlan()
    {
        $setting = Setting::where('name', '=', 'active_plan_id')->first();

        if ($setting) {
            return 'plan already activated';
        }

        $paypal = new Paypal();
        $plan = $paypal->activatePlan();

        if ($plan) {
            return 'success';
        } else {
            return 'failure';
        }
    }

    public function redirectToPaypal()
    {
        $paypal = new Paypal();

        return $paypal->createBillingAgreement();
    }

    public function executeAgreement()
    {
        // ## Approval Status
        // Determine if the user accepted or denied the request
        if (isset($_GET['success']) && $_GET['success'] == 'true') {
            $paypal = new Paypal();
            $token = $_GET['token'];
            $agreement = new Agreement();

            // ## Execute Agreement
            // Execute the agreement by passing in the token
            $agreement->execute($token, $paypal->apiContext);

            // ## Get Agreement
            // Make a get call to retrieve the executed agreement details
            $agreement = Agreement::get($agreement->getId(), $paypal->apiContext);

            dd($agreement);
        }
    }

    public function registerPrimaryWebhooks()
    {
        $paypal = new Paypal();

        return $paypal->registerPrimaryWebhooks();
    }

    public function handlePrimaryWebhooks()
    {
        $paypal = new Paypal();

        return $paypal->validatePrimaryWebhooks();
    }
}

<?php

namespace App\Http\Controllers;

use App\Setting;

use App\Logic\Paypal\Paypal;

use Illuminate\Http\Request;

use PayPal\Api\Agreement;

class PaypalController extends Controller

{

public function createAndActivatePlan()

{

$setting = Setting::where('name', '=', 'active_plan_id')->first();

if ($setting) {

return 'plan already activated';

}

$paypal = new Paypal();

$plan = $paypal->activatePlan();

if ($plan) {

return 'success';

} else {

return 'failure';

}

public function redirectToPaypal()

{

$paypal = new Paypal();

return $paypal->createBillingAgreement();

}

public function executeAgreement()

{

// ## Approval Status

// Determine if the user accepted or denied the request

if (isset($_GET['success']) && $_GET['success'] == 'true') {

$paypal = new Paypal();

$token = $_GET['token'];

$agreement = new Agreement();

// ## Execute Agreement

// Execute the agreement by passing in the token

$agreement->execute($token, $paypal->apiContext);

// ## Get Agreement

// Make a get call to retrieve the executed agreement details

$agreement = Agreement::get($agreement->getId(), $paypal->apiContext);

dd($agreement);

}

public function registerPrimaryWebhooks()

{

$paypal = new Paypal();

return $paypal->registerPrimaryWebhooks();

}

public function handlePrimaryWebhooks()

{

$paypal = new Paypal();

return $paypal->validatePrimaryWebhooks();

}

Here is also my PayPal routes in case you need it

<?php

// PayPal
Route::get('/paypal/create-and-activate-plan', 'PaypalController@createAndActivatePlan');
Route::get('/paypal/register-primary-webhooks', 'PaypalController@registerPrimaryWebhooks');
Route::get('/paypal/redirect-to-paypal', 'PaypalController@redirectToPaypal');
Route::get('/paypal/execute-agreement', 'PaypalController@executeAgreement');
Route::post('/paypal/webhooks/primary', 'PaypalController@handlePrimaryWebhooks');

<?php

// PayPal

Route::get('/paypal/create-and-activate-plan', '[email protected]');

Route::get('/paypal/register-primary-webhooks', '[email protected]');

Route::get('/paypal/redirect-to-paypal', 'Payp[email protected]');

Route::get('/paypal/execute-agreement', '[email protected]');

Route::post('/paypal/webhooks/primary', '[email protected]');

Coding