Module reactive_mutiny::stream_executor

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Contains the logic for executing [Stream] pipelines on their own Tokio tasks with zero-cost Instruments options for gathering stats, logging and so on.
Four executors are provided to attend to different Stream output item types:

  1. Items that are non-futures & non-fallible. For instance, Stream::Item = String
  2. Items that are futures, but are non-fallible: Stream::Item = Future<Output=DataType> – DataType may be, for instance, String
  3. Items that are non-futures, but are fallible: Stream::Item = Result<DataType, Box<dyn std::error::Error>>
  4. Items that are fallible futures: Stream::Item = Future<Output=Result<DataType, Box<dyn std::error::Error>>> – allowing futures to time out

Apart from handling the specific return types, logging & filling in the available metrics, all executors do the same things:

  1. Register start & finish metrics
  2. Log start (info), items (trace) and finish (warn)

Specific executors do additional work:

  1. Streams that returns a Result: logs & counts untreated-errors (errors that made it all the way through the pipeline and ended up in the executor), calling the provided on_err_callback();
  2. Streams that returns a Future: they will, optionally, compute the time for each future to complete and, also optionally, register a time out for each future to be completed – cancelling the Future if it exceeds the time budget.

Structs