ios - Chaining dependent observables -


i need create dependent api calls second 1 needs value returned first one. first thing comes mind using flatmap

apimanager.shared     .createreport(report: report)     .flatmap { (report) -> observable<report> in         return apimanager.shared.createreportstep(reportid: report.id)     }

createreport returns observable<report> after successfull call returns updated report model(with id), after need call api create report step, report.id needed.

everything looks , works fine code, problem comes when need after each of these steps(createreport , createreportstep). placed code in onnext block, called once, after both of steps completed.

is there way receive onnext signal after both steps? use this:

apimanager.shared       .createreport(report: report)       .concat(apimanager.shared.createreportstep(reportid: report.id))

which emmit 2 signals want, again updated report.id pass createreportstep?

if don't mind time component , need have access both report , returned createreportstep(reportid:), go creating tuple in flatmap's block

apimanager.shared     .createreport(report: report)     .flatmap { (report) -> observable<report> in         return apimanager.shared.createreportstep(reportid: report.id)             .map { (report, $0) }     }

the resulting observable contain both results in tuple.

if time component important, following

let report = apimanager.shared   .createreport(report: report)   .share()  let reportstep = report.map { $0.id }.flatmap(apimanager.shared.createreportstep)  observable.concat([report, reportstep])

here, important bit share call. ensure createreport performs work once, have 2 next events requested.


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