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

Comments

Post a Comment

Popular posts from this blog

Understanding your WSL2 RAM and swap - Changing the default 50%-25%

Image
The Windows Subsystem for Linux operates as a virtual machine that can dynamically grow the amount of RAM to a maximum set at startup time.  Microsoft sets a default maximum RAM available to 50% of the physical memory and a swap-space that is 1/4 of the maximum WSL RAM.  You can scale those numbers up or down to allocate more or less RAM to the Linux instance. The first drawing shows the default WSL memory and swap space sizing. The images below show a developer machine that is running a dev environment in WSL2 and Docker Desktop.  Docker Desktop has two of its own WSL modules that need to be accounted for.  You can see that the memory would actually be oversubscribed, 3 x 50% if every VM used its maximum memory.  The actual amount of memory used is significantly smaller allowing every piece to fit. Click to Enlarge The second drawing shows the memory allocation on my 64GB laptop. WSL Linux defaults to a maximum RAM size of 5
Read more

DNS for Azure Point to Site (P2S) VPN - getting the internal IPs

Image
I wanted to access all my Azure resources without making any of them visible to the Internet.   The easiest give my local machine access to everything on my Azure Virtual Network (VNET) was to connect to it over VPN. It turns out creating Azure VPN gateways and connecting to Azure VPN endpoints is easy.  There are some subtleties in getting DNS name resolution to work that can confuse when first starting out. Setting the Stage There are a few ways to get to Azure endpoints and resources that are blocked from the internet.  We can  Create a Point-to-Site connection from our local machines to Azure Network Gateways Create a Site-to-Site network connection from our local networks to Azure Network Gateways. Use Bastion Hosts Use Cloud Shell Leave everything open to the internet. I chose a Point-to-Site (P2S) VPN connection that connects from my laptop to a VNet Gateway.  That joins my laptop
Read more

Installing the RNDIS driver on Windows 11 to use USB Raspberry Pi as network attached

Image
I do a lot of my development and configuration via ssh into my Raspberry Pi Zero over the RNDIS connection. Some models of the Raspberry PIs can be configured with  gadget drivers  that let the Raspberry pi emulate different devices when plugged into computers via USB. My favorite gadget  is the network profile that makes a Raspberry Pi look like an RNDIS-attached network device.  All types of network services travel over an RNDIS device without knowing it is a USB hardware connection. A Raspberry Pi shows up as a Remote NDIS (RNDIS) device when you plug the Pi into a PC or Mac via a USB cable. The gadget  in the Windows Device Manager picture shows this RNDIS Gadget connectivity between a Windows machine and a Raspberry Pi. The Problem Windows 11 and Windows 10 no longer auto-installs the RNDIS driver that makes magic happen. Windows recognizes that the Raspberry Pi is some type of generic USB COM device. Manually running W indows Update  or  Update Driver  does  not  install the RNDI
Read more