When NetworkManager starts, NMSecretAgentOld gets a name-owner changed
signal and registers right away.
Especially since commit ce0e898fb4 ('libnm: refactor caching of D-Bus
objects in NMClient') this hits a race where NetworkManager does not yet
export the org.freedesktop.NetworkManager.AgentManager interface and
the registration fails:
GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod: No such interface “org.freedesktop.NetworkManager.AgentManager” on object at path /org/freedesktop/NetworkManager/AgentManager
Previously, when NMClient recevied a name-owner changed, that would
block the main loop long enough to avoid the race. Note that NMClient
has nothing to do with NMSecretAgentOld, however in practice all
applications that use NMSecretAgentOld also use NMClient.
While we should fix the race server-side, we also need to work around it
in the client. Retry.
Also, make the async request actually cancellable and actually honor the passed
GCancellable.
Check output:
$ LIBNM_CLIENT_DEBUG=trace ./clients/cli/nmcli agent secret |& grep secret-agent
libnm-dbus: <trace> [21399.04862] secret-agent[2f2af4ee102d7570]: create new instance
libnm-dbus: <trace> [21399.04863] secret-agent[2f2af4ee102d7570]: init-sync
libnm-dbus: <trace> [21404.08147] secret-agent[2f2af4ee102d7570]: name owner changed: (null)
libnm-dbus: <trace> [21404.09085] secret-agent[2f2af4ee102d7570]: name owner changed: ":1.2504"
libnm-dbus: <trace> [21404.09085] secret-agent[2f2af4ee102d7570]: register: starting asynchronous registration...
libnm-dbus: <trace> [21404.09178] secret-agent[2f2af4ee102d7570]: register: registration failed with error "GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod: No such interface “org.freedesktop.NetworkManager.AgentManager” on object at path /org/freedesktop/NetworkManager/AgentManager". Retry in 0 msec...
libnm-dbus: <trace> [21404.09178] secret-agent[2f2af4ee102d7570]: register: retry registration...
libnm-dbus: <trace> [21404.09195] secret-agent[2f2af4ee102d7570]: register: registration failed with error "GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod: No such interface “org.freedesktop.NetworkManager.AgentManager” on object at path /org/freedesktop/NetworkManager/AgentManager". Retry in 4 msec...
libnm-dbus: <trace> [21404.09236] secret-agent[2f2af4ee102d7570]: register: retry registration...
[...]
libnm-dbus: <trace> [21405.01782] secret-agent[2f2af4ee102d7570]: register: registration failed with error "GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod: No such interface “org.freedesktop.NetworkManager.AgentManager” on object at path /org/freedesktop/NetworkManager/AgentManager". Retry in 128 msec...
libnm-dbus: <trace> [21405.03063] secret-agent[2f2af4ee102d7570]: register: retry registration...
libnm-dbus: <trace> [21405.03068] secret-agent[2f2af4ee102d7570]: register: registration failed with error "GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod: No such interface “org.freedesktop.NetworkManager.AgentManager” on object at path /org/freedesktop/NetworkManager/AgentManager". Retry in 128 msec...
libnm-dbus: <trace> [21405.04354] secret-agent[2f2af4ee102d7570]: register: retry registration...
libnm-dbus: <trace> [21406.01097] secret-agent[2f2af4ee102d7570]: register: registration succeeded