The PHP SDK for the SOAP API

The SDK is composed of API Services and user profiles that define characteristics of the users of those services. This section includes the following topics:

l	“Configuring PHP and Apache for the SDK”

l	“Supported Standards”

l	“Downloading and Installing the SDK”

l	“SDK Directories and Configuration Files”

l	“API Services”

l	“Profiles”

l	“Sample Applications”

This chapter details the software and hardware supported and required by the PayPal SDK and its installation.

Configuring PHP and Apache for the SDK

The PHP SDK relies on the following required PHP packages:

l

NET_Url

l	NET_Socket

l	HTTP_Request

l

Log

Configure PHP and Apache as follows to use the PayPal SDK:

1.	Disable safe mode features.

2.	Do not use the disabled_functions and disabled_classes settings.

3.	Install PHP as an Apache Web Server module. This instructions apply to PHP 4.3.0 or 5.1.4 on Microsoft Windows:

–	Insert the following lines into your Apache httpd.conf (which is usually located in C:\Program Files\Apache Group\Apache2\conf)

# For PHP 4 do something like this:

LoadModule php4_module "c:/php/php4apache2.dll"

# Don't forget to copy the php4apache2.dll file from the sapi directory!

AddType application/x-httpd-php .php

# For PHP 5 do something like this:

LoadModule php5_module "c:/php/php5apache2.dll"

AddType application/x-httpd-php .php

# configure the path to php.ini

PHPIniDir "C:/php"

–	Go to your PHP installation directory and edit the php.ini file. Find extensions section, and uncomment (remove the semicolons at the beginning) the following two lines:

;extension=php_curl.dll

;extension=php_openssl.dll

4.	Verify your PHP configuration with the following command, which displays your PHP configuration

php –info

Supported Standards

The PayPal SDK has been verified to work with the following standards.

Table D.1

Supported Standards

Standard	Version
PHP with PHP Extension and Application Repository (PEAR)	4.3.*
Simple Object Access Protocol (SOAP)	1.1
Web Services Description Language (WSDL)	1.1

Supported Human Languages

The PayPal SDK is available in U.S. English.

SDK Version Number

This guide describes PayPal PHP SDK version 4.3.1.

Downloading and Installing the SDK

The latest version of the PayPal SDK is available at https://www.paypal.com/sdk.

Be sure you have configured PHP and your web server as detailed in “Configuring PHP and Apache for the SDK”.

You can install the SDK on a local computer or on a remote computer.

Installing on Local Computer

Follow these steps to install the SDK on your local computer.

1.	Download the PHP SDK in your desired distribution format: .zip, .tar, or .tar.gz.

2.	Extract the distribution to your installation directory (indicated in these steps as install_dir) with one of the following commands:

unzip paypal_php_sdk.zip

tar vxf paypal_php_sdk.tar

tar vxfz paypal_php_sdk.tar.gz

3.	Install the samples with the following steps:

cd install_dir\php-sdkphp install.php

4.	When you are prompted for your target web directory, enter the name of your PHP web directory. The target directory must be under the document root of the PHP server.

Installing on Remote Computer from Microsoft Windows

You can install the SDK to a remote computer that runs an FTP server.You need to know the following information to complete the remote installation:

l	The FTP server name

l	Your FTP username and password

l	The directory for the SDK itself. This must be relative to the FTP root directory.

l	The directory for the SDK samples. This must be relative to the FTP root directory.

Follow these steps to install the SDK on your local computer.

1.	Download a distribution format for the PHP DSK: .zip, .tar, or .tar.gz.

2.	Extract the distribution to your installation directory (indicated in these steps as install_dir) with one of the following commands:

unzip paypal_php_sdk.zip

tar vxf paypal_php_sdk.tar

tar vxfz paypal_php_sdk.tar.gz

3.	Install the SDK and samples with the following steps at the command prompt:

cd install_dir\php-sdk

remote_intall.bat

4.	Follow the prompts until the installation finishes.

Example Remote Installation

C:\php-sdk>remote_install.bat

This installer will overwrite any existing files in the target directory. To cancel, press Control-C and then Y.

Press any key to continue . . .

Enter the FTP server to install on: yourDomainName

Username for FTP: yourFTPusername

Password for FTP: yourFTPpassword

Please enter the path (relative to your FTP root) for the paypal-php-sdk directory: yourRemoteInstallDirectory

Please enter the path (relative to your FTP root) for the paypal-sdk-samples directory: yourRemoteInstallDirectoryInThePHPDocumentRoot

SDK Directories and Configuration Files

The PHP SDK components are organized into different subdirectories, as shown below”

Table D.2

PayPal SDK for PHP: Directories and Contents

Directory	Descrption
lib	Primary SDK code. Subdirectories are described in Table D.3, “lib Subdirectories and Contents.”
docs	SDK documentation: examples, sample XML, and API documentation
samples	Sample applications

Table D.3

lib Subdirectories and Contents

Directory in lib	Descrption
PayPal	Main SDK classes, configuration files, and ancillary files
PayPal/cert	PayPal public certificates
PayPal/conf	SDK system properties configuration file. See “Configuration File”.
PayPal/Profile	APIProfile and EWPProfile implementations and the ProfileHandler definitions, with two deafult profile handlers: ProfileHandler_File and ProfileHandler_Array.
PayPal/SOAP	PEAR::SOAP implementation. No PayPal-specific code.
PayPal/Type	Auto-generated data type files from which the PayPal type classes inherit, and two parent classes: XSDType and XSDSimpleType.
PayPal/wsdl	PayPal WSDL/XSD files and paypal-endpoints.php

Configuration File

The PayPal SDK is distributed with the configuration properties file SDK_root/lib/PayPal/conf/paypal-sdk.php.dist.

If you want to change the configuration, copy this file to:

SDK_root/lib/PayPal/conf/paypal-sdk.php

SDK Logging

The PayPal SDK uses PEAR’s logging capability.

Setting Log Levels

The SDK varies the amount of detail it logs according to three logging levels.

Set the value of the log_level parameter in the SDK_root/lib/PayPal/conf/paypal-sdk.php file.

Table D.4

SDK Logging Levels

Level	Description
PEAR_LOG_ERR	Log only severe errors
PEAR_LOG_INFO	Default log level. Date/time of API operation, operation name, elapsed time, success or failure indication.
PEAR_LOG_DEBUG	Full text of SOAP requests and responses and other debugging messages. Because SOAP requests and responses are asynchronous, the recording of requests and responses might appear out of sequence in the log file. Because DEBUG logging can degrade the performance of the SDK, be careful about using it for day-to-day operation.

Table D.5

SDK Logging Levels

Level	Description
ALL	Same as DEBUG
ERROR	Log only severe errors
INFO	Date/time of API operation, operation name, elapsed time, success or failure indication
DEBUG	Full text of SOAP requests and responses and other debugging messages. Because DEBUG logging can degrade the performance of the SDK, be careful about using it for day-to-day operation. Note: Because SOAP requests and responses are asynchronous, the recording of requests and responses might appear out of sequence in the log file.

Logfile Location

In the log_dir parameter, set the name of the directory where the SDK should write its logfile.

API Services

Integrated access to the PayPal Web Services APIs is one of the main features of the PayPal SDK. As shown in Figure D.1, “PayPal SDK API Services: High-Level View”, the PayPal SDK uses the underlying platform’s SOAP toolkit to communicate with the PayPal API endpoint. Stub classes representing the requests, the responses, and their data are provided to set request parameters and read response values. These classes are auto-generated from the PayPal WSDL file.

Figure D.1

PayPal SDK API Services: High-Level View

Profiles

Before the SDK can be used, it must know the profile of the user accessing its services. A profile is a collection of information about a merchant or developer who uses the PayPal SDK. An API profile is associated with API Services and includes:

l	A PayPal API username and password.

l	If you are using API Certificates, The path to the API certificate in PEM format as downloaded from PayPal

l	If you are using API Signatures, the signature string.

l	The optional name of a third-party who authorizes the caller to invoke PayPal APIs on his behalf. This third-party is called a subject.

l	The PayPal environment for processing API calls: live, sandbox or beta-sandbox.

An EWP profile is associated with EWP Services includes:

l	The path to the merchant’s local copy of that public certificate

l	The private key password for that public certificate

l	The path to a merchant’s private key file for digitally signing data

l	The URL to which the button form POSTs

l	The optional URL of a payment button image. The default is PayPal’s standard Buy Now button.

For more information about how EWP works, see the Website Payments Standard Integration Guide.

Overview to Profile-related Classes

The primary interfaces and classes for SDK profiles are described below.

Table D.6

Summary of PHP SDK Profile-related Classes

Interface/Class	Descriptions
APIProfile	This class defines the basic information that PayPal needs to know about a user of the PayPal Web Service APIs. Developers must create an instance of APIProfile for each account that accesses the APIs. For single-merchant developers, only a single APIProfile instance is needed. PayPal provides a default implementation suitable for the needs of most SDK developers. However, you are free to write a custom implementation if you need additional functionality the default class does not offer.
ProfileHandler	The ProfileHandler class manages the storage and retrieval of APIProfile and EWPProfile objects. PayPal provides two basic implementations: ProfileHandler_Array and ProfileHandler_File to serialize and deserialize the data in profiles to and from a file on the disk. For security, the ProfileHandler_File implementation does not store an API user’s API password.

Sample Applications

The PayPal SDK includes sample applications in the SDK_root/samples. The sample applications are divided into two groups:

1.	Website Payments Pro: Using the Direct Payment API for credit card charges and the Express Checkout APIs

2.	Administrative Samples: RefundTransaction, TransactionSearch, DoCapture, DoVoid, and DoReauthorization

Sample API User with API Signature

The samples come with an API Signature for use with the SDK and the PayPal Sandbox. This API Signature belongs to the following user:

Table D.7

Details of the SDK Sample API Signature

API Username	sdk-three_api1.sdk.com
API Password	QFZCWN5HZM8VBG7Q
API Signature	A‑IzJhZZjhg29XQ2qnhapuwxIDzyAZQ92FRP5dqBzVesOkzbdUONzmOU

Sample API User and Certificate

The samples come with a PayPal Web Services API digital certificate for use with the SDK and the PayPal Sandbox. This certificate belongs to the following user:

Table D.8

Details of the sdk-seller.p12 SDK Sample Certificate

Location of Certificate	SDK_root\samples\Certs\sdk-seller.p12
API Username	sdk-seller_api1.sdk.com
API Password	12345678
PKCS12 Passphrase	password

Running the Samples

Run the samples by opening the following URL:

http://yourWebServer:port/webDir/paypal_php_samples/

webDir will vary depending on the target PHP Web directory you specified to install.php when you installed the SDK.