b2a6b6cf36
A new embedded socket server for the metadata proxy is implemented. This new implementation mimics the implementation of the ``UnixDomainWSGIServer`` class. The server listens to a file socket that is populated by the HAProxy instance running inside the network metadata namespace. The HAProxy writes the requests of the virtual machines on the Unix file socket and the metadata proxy sends the requests to the Nova metadata server. This new implementation does not relies on ``neutron.api.wsgi.Server`` nor ``eventlet.wsgi.server``. It inherits from the built-in library class ``socketserver.StreamRequestHandler``. This implementation doesn't use ``oslo.services`` to spawn the processes or the local threads depending on the ``metadata_workers`` configuration variable. Right now only the embedded form (local thread) is implemented (metadata_workers=0, the default value). Future implementations will enable again this configuration variable. This patch also removes the use of ``oslo_service.launch`` to execute the agent main thread. This should be restored once this library removes the use of ``eventlet``. Closes-Bug: #2087942 Change-Id: I007fb7452d709f4b711d8efb9dea5f374de668b4
2.3 KiB
Eventlet Deprecation Reference
This document contains the information related to the
eventlet library deprecation. Each section describes how
each module has been migrated, the caveats, the pending technical debt
and the missing parts.
OVN Agent
Launch process
The execution of the OVN agent has been replaced. Instead of using
oslo_services.launch, that is still using eventlet, the
agent creates a threading.Event instance and holds the main
thread execution by waiting for this event.
Note
Once the oslo_services library removes the usage of
eventlet, the previous implementation will be restored. The
oslo_services.service.ProcessLauncher service launcher
implements a signal handler.
Metadata proxy
The UnixDomainWSGIServer class has been replaced with a
new implementation. This implementation does not rely on
neutron.api.wsgi.Server nor
eventlet.wsgi.server. It inherits from the built-in library
class socketserver.StreamRequestHandler.
Note
This implementation doesn't use oslo_services to spawn
the processes or the local threads depending on the
metadata_workers configuration variable. Right now only the
embedded form (local thread) is implemented
(metadata_workers=0, the default value). Future
implementations will enable again this configuration variable.