tao-pr / cats-playground

Collection of cats-effects / fs2 examples

cats-playground

An example cats-effect application built from the ce3.g8 template.

Configure the application

Cats-playground consists of multiple run modes which can be configured which to run. Check out application.conf. The config run-mode defines which mode to run.

Run application

sbt run

Run modes

The project includes following playground runners

Runner	Task	Using
CombinedJsonRunner	Streams (fs2) multiple JSON files, parses and combines them	fs2 (Files, Stream) Monoid
CsvToJsonRunner	Streams (fs2) multiple CSV files, parses them and writes in to multiple JSON files	fs2 (Files, Stream) Monoid
EvalRunner	Runs Evals as Fibers	Eval Fiber (join) OptionT
ForkRunner	Forks multiple Fibers with artificial wait time and shares atomic state across them	Ref Temporal Fiber
GenerateCsvRunner	Generates multiple CSV files and simulates errors	Parallel (parTraverse)
PiMCRunner	Simulates Pi estimation from Monte-Carlo method concurrently	Parallel (parTraverse)
RaceRunner	Generates racing conditions of multiple threads which can also throw exceptions	Fiber ApplicativeError (via F.raiseError) Temporal Concurrent (racePair)
SemaphoreRunner	Endlessly runs scheduler which only runs an execution when resources are available (and permitted)	Semaphore Ref Stream (awakeEvery)
AttemptRunner	Runs chains of operations which transforms data with functional error handling	Ior Validated Monoid (combineAll) Parallel (parTraverse)
IOBoundRunner	Runs IO-blocking task and CPU-bound task in parallel	Parallel (parTraverse) Temporal (sleep) Sync (blocking) parMapN

Good resources for cats-effects / cats-io / fs2

• Full API documentation
• Why Fibers are fast

Licence

MIT