NEWS

---

crew 0.10.2

• Eliminate spurious launch_max error from underutilized workers (#189).
• Deprecate launch_max in favor of crashes_error (#189).
• Look for crashes of all workers in rotate() instead of looking for crashes of a specific worker in launch() (#189).
• Add a crashes() launcher method to allow plugins to detect and respond to crashes more easily.
• Change default seconds_idle to 300.
• Move autometric to Suggests:.

crew 0.10.1 (2024-11-03)

• Instrument crew_eval() with autometric::log_phase_set() and autometric::log_phase_reset().

crew 0.10.0 (2024-10-11)

• Give full worker name in the worker launch error message (@multimeric).
• Start the controller automatically in more methods.
• Add an r_arguments argument to supply command line arguments to R for workers (#175, @rpruim).
• Add a cancel() controller method to cancel one or more tasks.
• Call cancel(all = TRUE) from terminate() as a safeguard.
• Make client$dispatcher a ps::ps_handle() handle and add a new client$client handle for the current process.
• To passively log memory usage when log_resources is given, the controller now calls log() as a side effect in most controller methods, with throttling to preserve speed.
• Return a status and status code from pop() etc.
• New internal function as_monad() makes error reporting more consistent.
• Use path.expand() on local log files.
• Switch to Rscript.
• Print session info from crew_worker() before attempting to dial into mirai.
• Add asyncdial = FALSE back to mirai::daemon() call.
• Deprecate local_log_directory and local_log_join in favor of crew_options_local() and the options_local argument.
• Add crew_options_metrics() and the options_metrics argument for recording resource metrics (#178).
• Add a new logging.Rmd vignette to explain best practices for logging and resource usage metrics (#178).

crew 0.9.5 (2024-06-24)

• CRAN patch.

crew 0.9.4 (2024-06-20)

• Do not use extended tasks in Shiny vignette.
• Add a new retry_tasks argument with default TRUE (#170).
• Avoid Base64 encoding functions from nanonext

crew 0.9.3 (2024-05-22)

• Deprecate native crew promises in favor of native event-driven promises in mirai (#162).
• Update the shiny.Rmd and promises.Rmd vignette to recommend native event-driven mirai promises (#162).

crew 0.9.2 (2024-04-24)

• Use .args rather than ... in mirai::mirai() to make sure arguments continue to be passed as local variables in mirai >= 0.13.1.9012.
• Add new controller methods autoscale(), descale(), and started() to facilitate different kinds of Shiny apps.
• Deprecate the scale and throttle methods of controller$promise(). promise() now always calls autoscale() to make sure one and only one auto-scaling loop is running asynchronously. Auto-scaling thus continues even after the promise resolves.
• Add a second example vignette that simulates coin flips.
• Add a new error argument to collect() (#166).

crew 0.9.1 (2024-03-25)

• Rewrite the async Shiny vignette with crew promises and Shiny extended tasks (#157, @jcheng5).
• Clarify the intent of controller$promise(mode = "one") in the vignette on promises (@jcheng5).
• Implement an error argument in pop() which may help with integration with ExtendedTask (@jcheng5).
• Handle task errors in the Shiny vignette (@jcheng5).

crew 0.9.0 (2024-02-08)

• Require nanonext >= 0.12.0 and mirai >= 0.12.0.
• Return to always re-launching backlogged inactive workers (#79, https://github.com/shikokuchuo/mirai/discussions/95).
• Implement push_backlog() and pop_backlog() to manage cases when it is not desirable to push to saturated controllers (https://github.com/ropensci/targets/issues/1220).
• Invisibly return the mirai object of a task pushed to the controller. This allows users to interact with the task directly, e.g. to create a promise object with promises::as.promise() (#146, @jcheng5).
• Add a new walk() method for controllers and controller groups to submit tasks in batch and return control immediately without waiting for any task to complete (#148, @jcheng5).
• Revive the collect() method for popping multiple tasks at once (#148, @jcheng5).
• Add controller group methods nonempty(), resolved(), unresolved(), and unpopped() to help with #148.
• Make the mirai dispatcher error message extremely verbose.

crew 0.8.0 (2024-01-09)

• Configure workers to send themselves a termination signal if the connection to the dispatcher is broken (#141, @psychelzh). Huge thanks to @shikokuchuo for the support through https://github.com/shikokuchuo/mirai/issues/87, https://github.com/shikokuchuo/mirai/pull/88, and https://github.com/shikokuchuo/nanonext/pull/25! The signal itself is platform-dependent and determined by the new function crew_terminate_signal().
• Implement crew_monitor_local() to help users monitor and terminate local R processes created by crew and mirai.
• Implement new utility function crew_terminate_process() to terminate a process manually without resorting to SIGKILL on Windows.
• Throw a warning from controller$map() if at least one task threw one. warnings = FALSE suppresses this behavior.
• Set output = TRUE in daemon() so stdout and stderr streams print.
• Add new arguments local_log_directory and local_log_join to write to local log files.

crew 0.7.0 (2023-12-11)

• Migrate from asyncdial to autoexit.
• Use Sys.info()[["user"]] to get the user in crew_clean() (#135, @luwidmer).
• Use condition variables to wait for tasks more efficiently (#108).
• Because of #108, controller$map() can no longer be used if there are tasks waiting to be popped.
• Use a cli progress bar in map().
• Encapsulate non-function R6 members in the private list and add active bindings where interfaces are necessary (#137). Ad hoc tests that absolutely need to modify private objects can use object$.__enclos_env__$private trick, but these tests should be skipped on CRAN in case there is a change to R6 that breaks this.
• Drop .signal from mirai::mirai() since all mirai tasks signal as of mirai version 0.11.2.9025.
• Implement crew_throttle(), a decoupled mechanism for throttling that can be applied to scaling.
• Bring back the throttle argument, powered by crew_throttle().
• Retry mirai::status() again in daemons_info() and make it configurable using seconds_interval and seconds_timeout in both the client and the launcher (#128).

crew 0.6.0 (2023-10-12)

• Migrate checks to enforce features in version 0.5.0 for reverse dependencies.
• Drop check of backlogged workers, c.f. https://github.com/shikokuchuo/mirai/discussions/63#discussioncomment-7051889 (#79, #124, @shikokuchuo).
• Deprecate seconds_exit because exitlinger in mirai is now obsolete (#125, @shikokuchuo).
• Use mirai::nextget("cv") to count unresolved tasks instead of looping through all the task objects (#131).
• Remove throttling and collect() in auto-scaling. Simplifies much of the code. Made possible by the efficiency gains in #131.
• Simplify wait().
• seconds_interval in map() no longer defaults to controller$client$seconds_interval.
• launcher$terminate_workers() terminates one or more workers, and launcher$terminate terminates the whole launcher.
• Add infrastructure to let custom launcher plugins launch and terminate workers asynchronously (#133). Launchers can set a positive number in the processes field to set the number of local mirai daemons for asynchronous requests to launch and terminate the serious workers. Then, launch_worker() and terminate_worker() can optionally make use of launcher$async$eval() to send these asynchronous calls.

crew 0.5.0 (2023-09-18)

• Suppress interactive browser on Windows which launched on each worker previously (@psychelzh).
• Migrate to the new host/daemon nomenclature in mirai 0.9.1 (#96).
• Suppress status() retries (@shikokuchuo, #100).
• Implement launch_max to error out if workers repeatedly launch without completing any tasks (#101, @shikokuchuo, @multimeric).
• Detect discovered workers more robustly in launcher$done().
• Add a new algorithm argument to the push(), shove(), and map() methods of controllers and controller groups, as well as arguments/fields in crew_eval() and its return value (#113, @shikokuchuo).
• As a default for pseudo-random number generation, leverage widely-spaced L'Ecuyer streams as supported by mirai::nextstream() (#115, @shikokuchuo).
• Move README documentation to vignettes.
• Add a new crew_tls() function for TLS configuration (#120).
• Deprecate the tls_enable and tls_config arguments of crew_client() etc. in favor of a tls argument which accepts crew_tls() objects (#120).

crew 0.4.0 (2023-07-10)

Highlights

• Use the TLS capabilities of nanonext and mirai.
• Add a map() method to the controller class for functional programming (#93).
• Fix bug in scale() which launched too many workers when active - demand was less than 0.
• Add crew_clean() to help clean up any lingering dispatchers and workers from previous sessions.

Other improvements

• Remove temporary controller summary workaround that ensured CRAN compatibility with targets 1.1.3.
• Add guardrails to make sure the controller is started for methods that require this. Part of this involved improving the error messages.
• Retry daemons() in daemons_info().

crew 0.3.0 (2023-06-26)

• Track warnings properly (#81, @brendanf).
• Optimize heavily (#81, #83, @shikokuchuo, @brendanf).
• Use CRAN nanonext 0.9.0.
• Delegate the task pushing and collection logic to a new R6 schedule class (#84).
• Delegate auto-scaling to the launcher (#84).
• Drastically simplify internal logic (#84).
• Rename "router" to "client" and change the function signature of launch_worker() (#84). Unfortunately neither of these changes is back-compatible for third-party launcher plugins. However, the controller interface is still back-compatible, so targets remains unaffected.
• Terminate "lost" workers on websocket rotation.
• Allow NULL result in pop()$result[[1L]].
• Delegate summaries among the controller, schedule, launcher, and client.
• Default to the loopback address for the local controller.
• Use already cumulative assigned and complete stats from mirai 0.8.7.9029.
• Reorganize pkgdown reference and Rd families to clarify which parts are for end-users and which parts are for launcher plugin developers.
• Add controller$shove() and schedule$list() to support fast extensions for functional programming.
• Depend on mirai 0.9.0 or greater.

crew 0.2.1 (2023-05-22)

• Use packageStartupMessage().

crew 0.2.0

• Use .args instead of ... in mirai::mirai().
• Use set.seed() instead of withr::local_seed() (#67, @shikokuchuo).
• Add a vignette to showcase integration with Shiny, co-authored with @dwoodie and with helpful suggestions by @shikokuchuo.
• Drop rlang::duplicate() (#72, @shikokuchuo).
• Do not poll dispatcher availability when starting router objects (@shikokuchuo).
• Implement a saturated() controller method to support targets.
• Add a worker_index column to controller summaries.
• When relaunching workers, prioritize those with unresolved tasks stuck at the NNG level (#75, @shikokuchuo).
• Always relaunch backlogged inactive workers (#79).
• Deprecate the auto_scale argument/field of controllers in favor of the scale argument of push(), pop(), and wait().
• Throttle auto-scaling with interval self$router$seconds_interval (#76).
• Remove clean() and instead terminate lost workers on launch.
• Fix examples.
• Add a collect argument to pop().

crew 0.1.1 (2023-04-21)

• Ensure checks pass on CRAN.

crew 0.1.0 (2023-04-19)

• Remove asyncdial from call to mirai::daemons().
• Explain vision in the launcher plugin vignette.
• Remove the superfluous clean() controller method.
• Clean up logic for scale() and launch() controller methods.
• Add a new inactive() launcher method to help with the above.
• Eliminate superfluous worker launches: clean up the controller logic, and check worker discoveries before worker connections (#51).
• Simplify the launcher plugin interface (#54).
• Commit to using the fast nanonext::.unresolved() (#49).
• Rename the callr launcher to the local process launcher (#56).
• Switch from SHA224 to SHA1 as the hash for random tokens and names (#59, @shikokuchuo).
• Open and confirm bus socket listeners asynchronously in the launcher abstract class (#58).
• Use condition variables to test the connection status of worker instances (#57, @shikokuchuo).
• Allow the dispatcher process to not exist so that the router will keep working if mirai implements the dispatcher another way (#60).
• Add a substitute argument to push() (#63).
• Remove dependency on custom NNG bus sockets, which significantly simplifies the internals, improves robustness, and smooths the integration with mirai (#61).
• Use processx instead of callr for the local process launcher (#64").
• Speed up crew_eval() by e.g. relying on nanonext::mclock() for the time.
• Add an empty() method to check if the controller or controller group is empty.
• Rely on mirai for globals cleanup, garbage collection, and global option resets (#65).
• Expose the package unloading capabilities of mirai (#65).
• Make monads classed environments and leave tibbles to the last minute in pop().
• Rename crew_wait() to crew_retry().
• Export crew_assert() and crew_random_name() to help launcher plugins.
• Rename the listen() method to start() in the router class.
• The poll() method now retries mirai::daemons() for robustness.
• crew_retry() gains a max_tries argument.
• Bug fix: stop setting router$daemons to NULL in poll() when the connection has a momentary problem.
• Simplify listening().

crew 0.0.5 (2023-03-23)

• Write a call() method to make it easier to write custom launcher plugins.
• Add robust documentation and tests for custom launcher plugins.
• Use as.character() to make sure the list argument supplied to rm() is safe. Fixes a test that was failing on R-devel with crew version 0.0.4.
• Remove the seconds_poll_high and seconds_poll_low fields and arguments for compatibility with mirai development and release versions.
• Hard-code the async_dial field in the router for compatibility with mirai development and release versions.

crew 0.0.4 (2023-03-21)

• Adjust references and tests as requested by CRAN.

crew 0.0.3

• First version.