CRAN patch

crew 0.9.5

• CRAN patch.

simplified Shiny/promises docs

crew 0.9.4

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

Delegate promises

crew 0.9.3

• 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).

minor patch

crew 0.9.2

• 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).

Shiny-related improvements

crew 0.9.1

• 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).

Promises and backlogged task management for {targets}

crew 0.9.0

• Require nanonext >= 0.12.0 and mirai >= 0.12.0.
• Return to always re-launching backlogged inactive workers (#79, shikokuchuo/mirai#95).
• Implement push_backlog() and pop_backlog() to manage cases when it is not desirable to push to saturated controllers (ropensci/targets#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.

Vital safety for workers using SIGTERM

• 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 shikokuchuo/mirai#87, shikokuchuo/mirai#88, and shikokuchuo/nanonext#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.

Event-driven wait()

crew 0.7.0

• 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).

Local async for plugins, simplification, and performance

crew 0.6.0

• Migrate checks to enforce features in version 0.5.0 for reverse dependencies.
• Drop check of backlogged workers, c.f. shikokuchuo/mirai#63 (comment) (#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.

Robustness, random numbers, and TLS configuration

crew 0.5.0

• 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).