The OpenShift installer modifies /etc/resolv.conf then tests the new
resolver configuration, however, there was no mechanism to reload
resolv.conf in our reuseable interpreter.
https://github.com/openshift/openshift-ansible/blob/release-3.9/roles/openshift_web_console/tasks/install.yml#L137
This inserts an explicit call to res_init() for every new style
invocation, with an approximate cost of ~1usec on Linux since glibc
verifies resolv.conf has changed before reloading it.
There is little to be done for users of the thread-safe resolver APIs,
their state is hidden from us. If bugs like that manifest, whack-a-mole
style 'del sys.modules[thatmod]' patches may suffice.
The module the connection class is now loaded as is
"ansible.plugins.connection.mitogen_ssh", etc., which breaks the test.
Instead, check if the connection is an instance of the base Connection
class.
While adding support for non-new style module types, NewStyleRunner
began writing modules to a temporary file, and sys.argv was patched to
actually include the script filename. The argv change was never required
to fix any particular bug, and a search of the standard modules reveals
no argv users. Update argv[0] to be '', like an interactive interpreter
would have.
While fixing #210, new style runner began setting __file__ to the
temporary file path in order to allow apt.py to discover the Ansiballz
temporary directory. 5 out of 1,516 standard modules follow this
pattern, but in each case, none actually attempt to access __file__,
they just call dirname on it. Therefore do not write the contents of
file, simply set it to the path as it would exist, within a real
temporary directory.
Finally move temporary directory creation out of runner and into target.
Now a single directory exists for the duration of a run, and is emptied
by runner.py as necessary after each task invocation.
This could be further extended to stop rewriting non-new-style modules
in a with_items loop, but that's another step.
Finally the last bullet point in the documentation almost isn't a lie
again.
The module name comes from YAML via Jinja2.. it's always Unicode. Mixing
it into a temporary directory name produces a Unicode tempdir name,
which ends up in sys.argv via TemporaryArgv.
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.
David Wilson