[ARCHIVE] Incorrect Page Parameter Response

Archived 2022.11.20. Content moved to error scenarios and responses.

Question

What return code should be specified in the case of an incorrect 'page' parameter?

For example:

Given an Data Holder (DH) has 25 total records which would match a certain request, in that request the Accredited Data Recipient (ADR) specifies:

• page-size of 10 AND page=5

As the request is outside the total number of records available, some form of error should be returned, as page 5 does not exist in this case. Should the DH return:

• A 200 with no data?
• Page 1 by default?
• A 400-range error? (and which one in particular)
• Finally, where is this specified in the Consumer Data Standards?

Answer

The Consumer Data Standards around the treatment of the pagination parameters are in the pagination section: CDS pagination.

This section does not explicitly define the error response if an unavailable page is requested.  As no specific behaviour is defined, the interpretation is left to the Data Holder.  The following would both be considered valid responses based on the standards:

• A response of 200 with no records and meta data populated as per normal
• A response of 400, recognising that an invalid page setting could be considered a malformed request
• A response of 422 based on the interpretation of an invalid page number being valid according to the schema, but invalid based on business logic.  In this case an error payload must be supplied.