Application management : Tools : Web Services : Developing a Web service client : Session management
Session management
This section points out a number of common specifications for web services.
General
Web services can either access the application using a sessionID or an access key.
sessionID
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To reduce storing data in the PLN_SESSIONDATA table and improve performance, (stateless) in-memory sessionIDs are used for SOAP web services. Functionally, this means that sessions used by web services will no longer be visible in the Session data TSI.
General practice for web services is to ensure your own login and logout calls. This is needed because the web service must have a Planon session(ID) in order to work.
The standard use case is:
• Log in
• Execute work (for example, adding a number or persons to Planon).
• Log out
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Instead of using a sessionID, you can also use an access key.
Session resources
When using a sessionID, the following resource restrictions/specifications need to be taken into account:
• Session timeout: to prevent web services from retaining too many resources, there is a timeout for the web service session when it has not been used for 24 hours (default).
• Limited BOValue cache on web services sessions to 16 entries
• Close SessionData upon logging out in web service
• Created a SOAP session timeout in System Settings > Web application TSI.
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For more information, see Web application.
Access key
Instead of executing a login SOAP request to create a sessionID and pass that as parameter to each request, you can also pass an access key.
This makes it possible to directly call SOAP web services by using an access key. It is then no longer required to call login / logout to fetch and release a sessionID.
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•    Using an access key could be slightly less efficient than using a sessionID.
•    For more information, see Access keys.