SOAP
XML
Standards based
WSDL (a package to define all the methods) needs to be downloaded and saved to the server
System to system
State maintained
Built in security
OAuth or Session ID (OLD)
Can build Custom SOAP Web Services
Enterprise WSDL
Partner WSDL
REST
XML or JSON
REST has in-built discovery of the available methods / endpoints
Lightweight
Security usually via OAuth
Old via Session ID
Web service implementations
Expose your own APEX classes as REST Endpoints
GET POST DELETE PATCH PUSH
Bulk API uses REST See https://tddprojects.atlassian.net/wiki/pages/createpage.action?spaceKey=SF&title=Salesforce%20APIs&linkCreation=true&fromPageId=1310556166
Synchronous vs Asynchronous
Sync
Eg a transaction
Wait for a reply
Within the Salesforce limits
Async
Check back later if it’s done
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