Hybrid / Intermediary Exchange
0.1.0 - STU 1 Ballot

This page is part of the Hybrid / Intermediary Exchange (v0.1.0: STU1 Ballot 1) based on FHIR R4. The current version which supercedes this version is 1.0.0. For a full list of available versions, see the Directory of published versions

Exception Handling

After an originating system initiates an exchange, an exception could occur…

  • at the destination service

    or

  • at an intermediary that is helping route the exchange.

This section describes a base set of conventions for reporting these exceptions.

Approach for conveying destination and intermediary exceptions

Destination-reported exceptions

Exception HTTP status codes generated by the destination are passed through unchanged by the intermediary to the originator.

Intermediary-reported exceptions

When an intermediary experiences an exception (including no HTTP response from a downstream actor) it:

  • Stops the process of routing the request

  • Returns the associated HTTP status code

When an intermediary receives an exception reported by another intermediary, it passes the HTTP status code to the originator.

Examples

Situation HTTP Status Notes
Exceptions reported by an intermediary
Destination can’t be resolved 404 Not Found Indicates that the destination could not be determined based on the submitted FHIR service base URL
Attempt to connect to destination server timed out (with no response) 504 Gateway Timeout Indicates that a timeout occurred when trying to reach the destination server. Resource that the gateway was trying to connect to timed out
System error 500 Internal Error The server may not be able to generate an OperationOutcome in a system error situation
Exceptions reported by the destination
Submitted URL path returned Page/Resource Not Found 404 Not Found Generated by the destination, regardless of whether using direct connect or an intermediary. Intermediary passes through the status code and OperationOutcome if returned by the destination
Invalid request (e.g., bad query content) 400 Bad Request as above
System Error 500 Internal Error as above