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| def readResultWithOffset[A, B]( | |
| check: Option[Query[A, Long]], | |
| query: Query[A ~ Long ~ Long, B], | |
| args: A, | |
| message: String, | |
| chunksize: Int, | |
| limit: Long = Long.MaxValue | |
| ) = | |
| val checkResult = | |
| sessionPool | |
| .use(session => { | |
| session | |
| .prepare(check.get) | |
| .toScopedZIO | |
| .flatMap(_.unique(args).retry(DefaultRetrySchedule)) | |
| }) | |
| .flatMap(n => if n > 0 then ZIO.succeed(n) else ZIO.fail(NoResult(message))) | |
| def loopResult(out: Queue[Take[StreamingError, B]], offset: Ref[Long], n: Long) = | |
| def resultStream(offset: Long, limit: Long) = | |
| sessionPool | |
| .use(session => { | |
| session | |
| .prepare(query) | |
| .toScopedZIO | |
| .flatMap(query => | |
| ZIO | |
| .succeed( | |
| query | |
| .stream(args ~ offset ~ limit, chunksize) | |
| .toZStream(chunksize) | |
| ) | |
| ) | |
| }) | |
| for | |
| rowsread <- offset.get | |
| result <- resultStream(rowsread, n - rowsread) | |
| _ <- result | |
| .runForeachChunk(c => offset.update(_ + c.size) *> out.offer(Take.chunk(c))) | |
| .ensuring(out.offer(Take.end)) | |
| yield () | |
| val result = | |
| for | |
| maxcount <- if check.isDefined then checkResult else ZIO.succeed(Long.MaxValue) | |
| n = math.min(maxcount, if limit < 1 then Long.MaxValue else limit) | |
| offset: Ref[Long] <- Ref.make(0L) | |
| out: Queue[Take[StreamingError, B]] <- Queue.bounded(chunksize) | |
| outstream = ZStream | |
| .fromQueueWithShutdown(out, out.capacity) | |
| .flattenTake | |
| _ <- loopResult(out, offset, n) | |
| .retry(DefaultRetrySchedule) | |
| .forkScoped | |
| yield outstream | |
| result.catchAll(catchAllErrors(message)) |
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