gabrielguerrero
commented
1 week ago The reason why the default is exhaushMap, is because the main cases I envision people using withCalls were for doing mutating calls to backend, and single entity get calls like load detail load user, essentially things that benefit from exhaust because blocks double clicking etc or multiple calls. I have withEntitiesLoadingCall which defaults to switchMap (and by the way has the same first problem but better to resolve in a separate issue), which I see people using more to load entities list because is more flexible, it can be combined with filtering sorting etc that do require the switchMap, because only the last call is important. I would prefer not to change the default because I think the previous reasons still apply, and if we change it, then it will really be a breaking change. I see that it could cause an issue because if the fetch obvservable doesn't completes after first value it needs to be switchMap otherwise subsequent calls will get block, the warning is not a bad idea if its not to complicated to implement probably using angular/core isDevMode, but otherwise I think is fine, I expect people that are providing an observable that returns more than one value will be digging more in the withCalls config anyway. It might be good if you add it to the withCalls docs as a warning at least.
Toeler
github-actions[bot]
Removes the
first()operator from thewithCallsresponse pipe. Allowing observables that emit multiple values to be returned, with an initial loading state and then no further loading state until the params trigger a new request.Warning: Potentially breaking change, as if the response does not complete, then the default
exhaustMapoperator will mean that subsequent triggers are ignored. The solution is to either useswitchMapor ensure that you complete.@gabrielguerrero Keen to discuss whether
exhaustMapis still the best default operator. Or whether you want different behaviour depending on whether the call is promise-returning or observable-returning? One other idea is that we could add a check that if the call returns an observable and doesn't complete after the first value is output and themapPipehas not been specified then have it throw some kind of error/warning.