/// Error handler for decoding fetch responses into an user defined error type. Will ignore successful responses.
let withErrorCancellable
(errorHandler: HttpResponse -> HttpContent -> CancellationToken -> Task<exn>)
(source: HttpHandler<HttpContent>)
: HttpHandler<HttpContent> =
fun next ->
{ new IHttpNext<HttpContent> with
member _.OnSuccessAsync(ctx, content) =
task {
let response = ctx.Response
match response.IsSuccessStatusCode with
| true -> return! next.OnSuccessAsync(ctx, content)
| false ->
ctx.Request.Metrics.Counter Metric.FetchErrorInc ctx.Request.Labels 1L
let! err = errorHandler response content ctx.Request.CancellationToken
return! next.OnErrorAsync(ctx, HttpException(ctx, err))
}
member _.OnErrorAsync(ctx, exn) = next.OnErrorAsync(ctx, exn)
member _.OnCancelAsync(ctx) = next.OnCancelAsync(ctx) }
|> source
