2.0 KiB
Add SIGINT protection to our pdbpp based debugger subystem such that for (single-depth) actor trees in debug mode we ignore interrupts in any actor currently holding the TTY lock thus avoiding clobbering IPC connections and/or task and process state when working in the REPL.
As a big note currently so called "nested" actor trees (trees with actors having more then one parent/ancestor) are not fully supported since we don't yet have a mechanism to relay the debug mode knowledge "up" the actor tree (for eg. when handling a crash in a leaf actor). As such currently there is a set of tests and known scenarios which will result in process cloberring by the zombie repaing machinery and these have been documented in https://github.com/goodboy/tractor/issues/320.
The implementation details include:
- utilizing a custom SIGINT handler which we apply whenever an actor's runtime enters the debug machinery, which we also make sure the stdlib's pdb configuration doesn't override (which it does by default without special instance config).
- litter the runtime with maybe_wait_for_debugger() mostly in spots where the root actor should block before doing embedded nursery teardown ops which both cancel potential-children-in-deubg as well as eventually trigger zombie reaping machinery.
- hardening of the TTY locking semantics/API both in terms of IPC terminations and cancellation and lock release determinism from sync debugger instance methods.
- factoring of locking infrastructure into a new ._debug.Lock global which encapsulates all details of the
triosync primitives and task/actor uid management and tracking.
We also add ctrl-c cases throughout the test suite though these are disabled for py3.9 (pdbpp UX differences that don't seem worth compensating for, especially since this will be our last 3.9 supported release) and there are a slew of marked cases that aren't expected to work in CI more generally (as mentioned in the "nested" tree note above) despite seemingly working when run manually on linux.