Now Connection.close() *must* be called in the worker, to ensure the
reference count for a context drops correctly.
Remove 'discriminator' for now, I'm not using it for testing any more
and it complicated this code.
This code is a car crash, it needs rewritten again. Ideally some/most of
this behaviour could live on services.DeduplicatingService somehow, but
I couldn't come up with a sensible design.
Closes#105.
References #155.
mitogen/service.py:
Refactor services to support individually exposed methods with
different security policies for each method.
- @mitogen.service.expose() to expose a method and set its policy
- @mitogen.service.arg_spec() to validate input.
- Require basic service message format to be a tuple of
`(method, kwargs)`, where kwargs is always a dict.
- Update DeduplicatingService to match the new scheme.
ansible_mitogen/connection.py:
- Rename 'method' to 'method_name' to disambiguate it from the
service.call()'s method= argument.
ansible_mitogen/planner.py:
- Generate an ID for every job, sync or not, and fetch job results
from JobResultService rather than via the initiating function
call's return value.
- Planner subclasses now get to select whether their Runner should
run in a forked process. The base implementation requests this if
the 'mitogen_isolation_mode=fork' task variable is present.
ansible_mitogen/runner.py:
Teach runners to deliver their result via JobResultService executing
in their indirect parent mux process.
ansible_mitogen/plugins/actions/mitogen_async_status.py:
Split the implementation up into methods, and more compatibly
emulate Ansible's existing output.
ansible_mitogen/process.py:
Mux processes now host JobResultService.
ansible_mitogen/services.py:
Update existing services to the new mitogen.service scheme, and
implement JobResultService:
* listen() method for synchronous jobs. planner.invoke() registers a
Sender with the service prior to invoking the job, then sleeps
waiting for the service to write the job result to the
corresponding Receiver.
* Non-blocking get() method for implementing mitogen_async_status
action.
* Child-accessible push() method for delivering task results.
ansible_mitogen/target.py:
New helpers for spawning a virginal subprocess on startup, from
which asynchronous and mitogen_task_isolation=fork jobs are forked.
Necessary to avoid a task inheriting potentially
polluted/monkey-patched parent environment, since remaining jobs
continue to run in the original child process.
docs/ansible.rst:
Add/merge/remove some behaviours/risks.
tests/ansible/integration:
New tests for forking/async.
* Use identical logic to select when stdout/stderr are merged, so
'stdout', 'stdout_lines', 'stderr', 'stderr_lines' contain the same
output before/after the extension.
* When stdout/stderr are merged, synthesize carriage returns just like
the TTY layer.
* Mimic the SSH connection multiplexing message on stderr. Not really
for user code, but so compare_output_test.sh needs fewer fixups.
The solution was that Mitogen's loader should emulate the behaviour of
ansible.executor.module_common, which restricts dependency scanning to
the ansible.module_utils namespace.