Classifying your return codes

Be explicit about your service behavior and service return codes.  REST is great but you need to understand the types of failures you can have.  Some may be actual failures.  Others may be successful service invocations with a failure to complete business operations because of business rules.

Document the meaning, ownership, and handling behavior of your Service return codes.  Do not assume your partner teams and calling systems have any expectations or understanding beyond success and not-success. 

Ask other teams, you call, for their Service return code documentation. Force them to document their expectations.

Proposed Return Code Category Types



Create response categories.  Determine the owner and expected behavior possibilities for each category for services you build.  The following is a basic categorization.


HTTP Code CategoryRemediation OwnerRemediation
SuccessEveryoneApplication or none required
Business ErrorBusinessManual process or Application rule
Technical ErrorIT / TechnologyManual
Embedded RedirectIT / TechnologyApplication Library
NACK / RetryIT / TechnologyLibrary and/or delayed retry mechanism

Asynchronous Messaging.

You can create the same types of categories for message-driven systems.  They can post return codes to reply/response queues or to event log capture streams.

Proposed Return Code Categories

Map each response code to one of the categories.  Make your application return the correct code for each service it provides. Implement the correct behavior for each service it invokes. The following is a sample list of proposed HTTP return code categories.

HTTP CodeReturn Code DescriptionDefault Contract Behavior
100ContinueTechnical Error
101Switching protocolTechnical Error
200OKSuccess
201CreatedSuccess
202AcceptedSuccess
203Non-Authorative InformationSuccess
204No ContentSuccess
205ResetSuccess
206Partial ContentSuccess
207Partial SuccessBusiness Error
300Multiple ChoicesTechnical Error
301Moved PermanentlyEmbedded Redirect
302FoundEmbedded Redirect
303See OtherEmbedded Redirect
304Not ModifiedTechnical Error
305Use ProxyTechnical Error
306UnusedTechnical Error
307Temporary RedirectEmbedded Redirect
308Permanent RedirectEmbedded Redirect
400Bad RequestBusiness Error
401UnauthorizedTechnical Error
402Payment RequiredTechnical Error
403ForbiddenTechnical Error
404Not FoundTechnical Error
405Method Not AllowedTechnical Error
406Not AcceptableTechnical Error
407Proxy Auth RequiredTechnical Error
408Request TimeoutTechnical Error
409ConflictTechnical Error
410GoneTechnical Error
411Length RequiredTechnical Error
412Precondition FailedTechnical Error
413Request Entity Too LargeTechnical Error
414Request-URI Too LongTechnical Error
415Unsupported Media TypeTechnical Error
416Request Ranage Not SatisfyableTechnical Error
417Expectation FailedTechnical Error
500Internal Server ErrorNack / Retry
501Not ImplementedTechnical Error
502Bad GatewayTechnical Error
503Service UnavailableNack / Retry
504Gateway TimeoutNack / Retry
505HTTP Version Not SupportedTechnical Error
N/AFailed to Route?

Related

* https://joe.blog.freemansoft.com/2016/10/classifying-your-return-codes.html
* https://joe.blog.freemansoft.com/2016/10/success-and-failure-in-world-of-service.html


Created 2016 Oct 04

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