Error Handling, Logging and Messaging

To aid in the testing, certification and sharing of click-to-install apps, developers are requested to provide graceful error handling for any OCLC Web services with which the app interacts.  When an error occurs, a human-readable and understandable error message should be displayed to the user consuming the application.

Some typical user error messages might include:

• Authentication failed
• No results
• Access denied due to permissions
• Create, Delete, or Update failed

In addition, to providing users with a human-readable error messages, developers should log error messages from OCLC's web services in order to faciliate debugging. OCLC's web services provide error messages via a variety of mechanisms including HTTP status codes, SRU error codes, and error messages within the response body itself. App error logs should include all of these types of information.