Do you have opinions on rest api error design Example Enteri

Question

Do you have opinions on rest api error design Example Entering a incorrect made up promo code Is this a http code 400 or 200 + json body error=INVALID PROMO CODE

streetsofboston · Answer

I prefer proper http error code responses Easy to check without the need to parse the body Eg a 200 body has one type of Json object response and a 500 body may have a another type of Json object response With an http response code that differs switching selecting the proper Json deserialization is easy

ursus · Answer

okay so you essentially have both right 400 + body where some json field says INVALID PROMO CODE

ursus · Answer

my gripe with http codes is that who knows what they mean 404 could mean the last resource is missing or some parent as well etc ambigious here the constant could help yea

streetsofboston · Answer

Yup Eg a 200 response will have a body of any Json that is needed required by the API call while a 4xx and or 5xx will have a fixed Json error message message eg error code and error message for its body

gildor · Answer

If it REST full it should return error code But IMO it s terrible API and any simple RPC based solution is much better solution Really wish history of API would be different

gildor · Answer

gt Easy to check without the need to parse the body You still have to parse body otherwise you will show wrong error message to user if this 400 means something else

gildor · Answer

so if you say that it s rest api it should really return error code in this case though it doesn t mean it s good by itself it s hard to work with it http error codes are always ambigious

streetsofboston · Answer

< gildor> I should have said Easy to check before the need to parse the body smiley The body of an error is often in a different format either totally different format or Json of a different type of object than a 200 response With an error code it s easier to select a deserializer that is appropriate for the returned response

ursus · Answer

< gildor> so whats your suggestion Just have a single non 200 error code and then exact error enum in body

gildor · Answer

Well I don t have suggestions we all cursed by REST

gildor · Answer

In my perfect world I wouldn t never use rest for internal API

gildor · Answer

But for rest yes you should find an error code which kinda works for you case 400 401 403 or whatever any who use it anyway will require to check docs and include an actual error code and message to error body response

gildor · Answer

< streetsofboston> well yes but it solves problem created by this approach when you have different error success format Also by using http statuses you forced to use different ones for different cases and rely on http protocol

ursus · Answer

what would you like in ideal world grpc never used that before how would they signal access tokens expired just some error=auth expired enum

gildor · Answer

Any rpc for a long time on my previous project we used solution similar to json rpc but just own internal it s super simple protocol actually Grpc has many other cool features though but it s of course very opinionated solution also requires additional friction for web Though I would love to use grpc it s indeed very powerful

gildor · Answer

For auth error you just return unique auth error code and in data any additional data

ursus · Answer

okay so whats your gripe with error codes that theyre ambigous without docs but they do same body deserializing though

gildor · Answer

Every method has list of errors not like 400 which just mean that client did something wrong on any level it may be even not an error but enum with result