The State of SOAP in PHP (ZC10 2010-11-02)

THE STATE OF SOAP IN PHP

David Zülke

David Zuelke

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Founder

Lead Developer

@dzuelke

WHAT IS SOAP? And How Did It All Start?

original plan

http://ﬂic.kr/kevinsteele/230997861/

however

http://de.wikipedia.org/wiki/Datei:Vorfeld_Terminal_1_I.JPG

http://en.wikipedia.org/wiki/File:Flughafenkontrolle.jpg

http://ﬂic.kr/himmelskratzer/2604824645/

NEIN NEIN NEIN NEIN DAS IST VERBOTEN

WHAT IS SOAP? And How Did It All Start?

Data Exchange Protocol

XML-based

language independent

platform independent

typically used for RPC-style Web Services

 zomg lol

ORIGINS A Brief (and Wildly Inaccurate) History Lesson

< 1998

XML-RPC

XML-RPC sucks

Simple Object Access Protocol 1.0

not really simple

renamed

Simple Object Access Protocol

SOAP 1.2

GLOSSARY Transports, Messages and WSDL

SOAP TRANSPORTS • Transports are used for message transmission • Most important ones: • HTTP/HTTPS • SMTP

Amazon

100.000.000.000 SOAP requests

(per second)

Sharks

(with friggin’ laser beams attached to their heads)

Custom Socket Transport and Serialization!

MESSAGES <?xml version="1.0" encoding="UTF-‐8"?> <SOAP-‐ENV:Envelope xmlns:SOAP-‐ENV="http:// schemas.xmlsoap.org/soap/envelope/" • Wrapped in <Envelope> xmlns:ns1="http://agavi.org/ sampleapp" > • <Header>s and a <Body> <SOAP-‐ENV:Body> <ns1:getProductResponse> <product> <id>123456</id> • Structure is identical for <name>Red Stapler</name> <price>3.14</price> Request and Response </product> </ns1:getProductResponse> </SOAP-‐ENV:Body> </SOAP-‐ENV:Envelope>

but worry not

that’s the entire point of SOAP

WSDL document

describes

• the service • the operations • the data types

<?xml version="1.0" encoding="utf-‐8"?> <wsdl:definitions xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http:// schemas.xmlsoap.org/wsdl/soap/" xmlns:soapenc="http://schemas.xmlsoap.org/soap/ encoding/" xmlns="http://schemas.xmlsoap.org/wsdl/" xmlns:tns="http://agavi.org/ sampleapp/types" xmlns:asa="http://agavi.org/sampleapp" name="AgaviSampleApplication" targetNamespace="http://agavi.org/sampleapp"> <wsdl:types> <xsd:schema xmlns:soap-‐enc="http://schemas.xmlsoap.org/soap/encoding/" targetNamespace="http://agavi.org/sampleapp/types"> <xsd:complexType name="Product"> <xsd:sequence> <xsd:element name="id" type="xsd:int"/> <xsd:element name="name" type="xsd:string"/> <xsd:element name="price" type="xsd:float"/> </xsd:sequence> </xsd:complexType> <xsd:complexType name="ArrayOfProducts"> <xsd:complexContent> <xsd:extension base="soap-‐enc:Array"> <xsd:attribute ref="soap-‐enc:arrayType" wsdl:arrayType="tns:Product []"/> </xsd:extension> </xsd:complexContent> </xsd:complexType> </xsd:schema> </wsdl:types> <wsdl:portType name="AgaviSampleApplicationPortType"> <wsdl:operation name="getProduct"> <wsdl:input message="asa:getProductRequest"/> <wsdl:output message="asa:getProductResponse"/>

AN EXAMPLE So We Are All on the Same Page

$client = new SoapClient('http://acme.com/product.wsdl', array( 'exceptions' => true, 'trace' => true, )); try { var_dump($client-‐>listProducts()); } catch(SoapFault $e) { // here be dragons } array 0 => object(stdClass)[3] public 'id' => int 8172401 public 'name' => string 'TPS Report Cover Sheet' (length=22) public 'price' => float 0.89 1 => object(stdClass)[4] public 'id' => int 917246 public 'name' => string 'Weighted Companion Cube' (length=23) public 'price' => float 129.99

by the way

I will not talk about non-WSDL modes

I'd rather stab myself than use SOAP without WSDL

SOAP CLIENTS If You Want To Consume Services OMNOMNOM SERVICE

BASICS $client = new SoapClient( 'http://acme.com/product.wsdl', // URL to WSDL describing the service array( // array of additional options for the client 'exceptions' => true, // throw SoapFault exceptions on errors 'trace' => true, // allow use of SoapClient::__getLast…() ) ); $allProducts = $client-‐>listProducts(); // $allProducts contains return value

GETTING AVAILABLE FUNCS $client = new SoapClient('http://acme.com/product.wsdl', array( 'exceptions' => true, 'trace' => true, )); var_dump($client-‐>__getFunctions()); array 0 => string 'Product getProduct(int $id)' (length=27) 1 => string 'ArrayOfProducts listProducts()' (length=30)

GETTING AVAILABLE TYPES $client = new SoapClient('http://acme.com/product.wsdl', array( 'exceptions' => true, 'trace' => true, )); var_dump($client-‐>__getTypes()); array 0 => string 'struct Product { int id; string name; float price; }' (length=55) 1 => string 'Product ArrayOfProducts[]' (length=25)

ADVANCED CONCEPTS Faults, Headers and Mappings

FAULT HANDLING $client = new SoapClient('http://acme.com/product.wsdl', array( 'exceptions' => true, 'trace' => true, )); try { $newThing = $client-‐>createProduct(new stdClass()); } catch(SoapFault $e) { // could be a client-‐side fault e.g. if fields are missing // or a server-‐side fault if the server had any objections :) }

SOAP HEADERS $client = new SoapClient('http://acme.com/product.wsdl', array( 'exceptions' => true, 'trace' => true, )); $client-‐>setSoapHeader( new SoapHeader('http://acme.com/soap/products', 'username', 'Chuck Norris') ); $client-‐>setSoapHeader( new SoapHeader('http://acme.com/soap/products', 'password', 'r0undh0usek!ck') ); // headers will be sent along with the request $allProducts = $client-‐>listProducts();

CLASSMAPS class Product { protected $id, $name, $price; // imagine getters and setters here } $client = new SoapClient('http://acme.com/product.wsdl', array( 'exceptions' => true, 'trace' => true, 'classmap' => array( 'Product' => 'Product', // no XML namespace here, which can be problematic… ), )); var_dump($client-‐>getProduct(123456)); object(Product)[2] protected 'id' => int 123456 protected 'name' => string 'Red Stapler' (length=11) protected 'price' => float 3.14

ext/soap cannot distinguish between identically named types from different namespaces

TYPEMAPS • Used for custom serialization and unserialization in rare cases • Example: • xsd:long is mapped to PHP int, overﬂows on 32bit archs • Needs two callbacks: • one for XML->PHP conversion • one for PHP->XML conversion

TYPEMAP EXAMPLE: XS:LONG you can use any name for this wrapper tag function to_long_xml($longVal) { return '<long>' . $longVal . '</long>'; } function from_long_xml($xmlFragmentString) { return (string)strip_tags($xmlFragmentString); } $client = new SoapClient('http://acme.com/products.wsdl', array( 'typemap' => array( array( 'type_ns' => 'http://www.w3.org/2001/XMLSchema', 'type_name' => 'long', 'to_xml' => 'to_long_xml', 'from_xml' => 'from_long_xml', ), ), ));

SOAP SERVERS Slightly More Complicated

A BASIC SERVER class ProductService { public function getProduct($id) { // witchcraft here return $product; } public function listProducts() { // more witchcraft here return $products; } } $server = new SoapServer('/path/to/local/products.wsdl', array(/* options… */)); // register a class to instantiate that has all the methods $server-‐>setClass('ProductService'); // alternative: use an existing instance $server-‐>setObject(new ProductService()); // rock and roll $server-‐>handle();

you can also register functions instead of class methods

wanna know how?

RTFM :X

DEALING WITH HEADERS class ProductService { public function getProduct($id) { // witchcraft here return $product; } public function listProducts() { // more witchcraft here return $products; } public function username($value) { // check if it's really chuck norris } public function password($value) { // check if he did a roundhouse kick } } $server = new SoapServer('/path/to/local/products.wsdl', array(/* options… */)); // register a class to instantiate that has all the methods $server-‐>setClass('ProductService'); // rock and roll $server-‐>handle();

again, it can’t tell headers from different namespaces apart

PRODUCING FAULTS class ProductService { public function getProduct($id) { if($product = ProductFinder::retrieveById($id)) { return $product; } else { return new SoapFault('Server', 'No such product'); } } public function listProducts() { // more witchcraft here return $products; } }

MULTI-PART RETURN VALUES <wsdl:message name="getTwoThingsRequest"> <wsdl:part name="id1" type="xsd:int"/> <wsdl:part name="id2" type="xsd:int"/> </wsdl:message> <wsdl:message name="getTwoThingsResponse"> <wsdl:part name="firstThing" type="tns:Product"/> <wsdl:part name="secondThing" type="tns:Product"/> </wsdl:message> class ProductService { public function getTwoThings() { // rocket science here return array($product1, $product2); } } list($p1, $p2) = $client-‐>getTwoThings($id1, $id2));

LITTLE SECRETS Did You Know That ext/soap Supports...

XML SCHEMA ARRAYS <complexType name="ArrayOfProducts"> <element name="products" type="foo:Product" maxOccurs="unbounded" /> </complexType> = <xsd:complexType name="ArrayOfProducts"> <xsd:complexContent> <xsd:extension base="soap-‐enc:Array"> <xsd:attribute ref="soap-‐enc:arrayType" wsdl:arrayType="tns:Product[]"/> </xsd:extension> </xsd:complexContent> </xsd:complexType>

HASHMAPS (W/ STRING KEYS) • Custom Apache Axis encoding style <xsd:schema • be aware that it won’t xmlns:apache-‐enc="http:// xml.apache.org/xml-‐soap"> offer good interoperability <xsd:complexType name="MyHashmap"> <xsd:element name="parameters" • Use any type for values, type="apache-‐enc:Map" /> </xsd:complexType> scalars for keys </xsd:schema> • Keys and values will use RPC encoding in the message

ONE-WAY CALLS • SOAP Operations may have only a request, without a response declared • BothSoapClient and SoapServer will close the connection as soon as they can when calling such a method http://ﬂic.kr/99996581@N00/1122331674/

LITTLE DISAPPOINTMENTS Things That ext/soap Does Not Support...

DateTime objects

but you can use type maps until there is support! o/

XSD:DATETIME TYPE MAP function to_datetime_xml(DateTime $dateTime) { return '<dateTime>'.$dateTime-‐>format('Y-‐m-‐dTH:i:sP').'</dateTime>'; } function from_datetime_xml($xmlFragmentString) { return new DateTime(strip_tags($xmlFragmentString)); } $client = new SoapClient('http://acme.com/products.wsdl', array( 'typemap' => array( array( 'type_ns' => 'http://www.w3.org/2001/XMLSchema', 'type_name' => 'dateTime', 'to_xml' => 'to_datetime_xml', 'from_xml' => 'from_datetime_xml', ), ), ));

DOCUMENT/LITERAL WRAPPED • Document style services yield messages that can be validated against the WSDL’s XML Schema • Unlike with RPC style services, such messages won’t contain the name of the called method anymore • Solution: wrap the message payload in an element that has the same name as the procedure you want to call • Not a problem in PHP, but you need to wrap/unwrap yourself

DOS AND DON’TS Keep This in Mind

enable the SOAP_SINGLE_ELEMENT_ARRAYS feature

don’t use SoapServer::fault()

use the exceptions option

double-check soap_use_error_handler()

don’t use cookies or other forms of state, ever

FRAMEWORK HIGHLIGHTS Zend Framework & Agavi

ZEND FRAMEWORK • Zend_Soap_Client as a wrapper for SOAPClient • Zend_Soap_Server as a wrapper for SOAPServer • Zend_Soap_Wsdl for constructing WSDL documents • Zend_Soap_Autodiscover for auto WSDL generation

Zend_Soap_Autodiscover generates WSDLs for you!

using PHPDoc comments

class AcmeProductService { /** * @param int The ID of the product. * * @return Product The product object. * * @deprecated Call Joe from sales if you want to know details about a product… */ public function getProduct($id) { // witchcraft goes here return $product; } } $autodiscover = new Zend_Soap_AutoDiscover(); $autodiscover-‐>setClass('AcmeProductService'); $autodiscover-‐>handle(); // only dumps a WSDL, does not start a server!

also very nice for prototyping

but might get difﬁcult with complex stuff

e.g. multi-dimensional arrays, can’t do those in PHPDoc

AGAVI • Re-use existing Actions for SOAP Services • Needs some information about the service in WSDL format • WSDL auto-generated by the Routing • Requires basic knowledge of XML Schema and WSDL • Supports Document/Literal Wrapped for Servers

SOAP VERSUS REST A Short Monologue

!e End

Questions?

THANK YOU! This was http://joind.in/2231 by @dzuelke

The State of SOAP in PHP (ZC10 2010-11-02)

by David Zuelke

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