x/sys/windows/svc/mgr: add Service.RecoveryActionsOnNonCrashFailures and Service.SetRecoveryActionsOnNonCrashFailures

[craig65535]

Proposal is at #59016 (comment)

---

What version of Go are you using (go version)?

$ go version
1.19.5

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

windows/amd64

What did you do?

Created a Windows service that requires recovery actions (such as restarting) that are executed when the service has exited with an error but has not crashed.

With a *mgr.Service (s), I attempted s.SetRecoveryActions and found that it did not support setting this flag.

What did you expect to see?

s.SetRecoveryActions should include the failure actions flag.

This is supported by ChangeServiceConfig2 but not the wrapper that exists in Service.SetRecoveryActions.

What did you see instead?

s.SetRecoveryActions can only set the recovery actions themselves, and the time at which each is active.

Proposal details

See #59016 (comment) where we propose adding API to access RecoveryActionsOnNonCrashFailures flag.

[craig65535]

I am able to work around this by calling windows.ChangeServiceConfig2() directly:

import (
	"github.com/winlabs/gowin32/wrappers"
	"golang.org/x/sys/windows"
	"golang.org/x/sys/windows/svc"
	"golang.org/x/sys/windows/svc/mgr"
)

...

	flag := wrappers.SERVICE_FAILURE_ACTIONS_FLAG{
		FailureActionsOnNonCrashFailures: 1,
	}
	err := windows.ChangeServiceConfig2(s.Handle, windows.SERVICE_CONFIG_FAILURE_ACTIONS_FLAG, (*byte)(unsafe.Pointer(&flag)))
	...

However, it seems like this should also be in the mgr package.

[cherrymui]

Does this require changing the signature of SetRecoveryActions, or adding a new method?

cc @golang/windows

[craig65535]

You could do either of those.SetRecoveryActions currently only takes a list of failure actions (passing SERVICE_CONFIG_FAILURE_ACTIONS to ChangeServiceConfig2), and there's no provision to support any of the other options provided by ChangeServiceConfig2 which are mainly single values and not lists. So, either it would need to change, or a new function could be added.

[alexbrainman]

Hello @craig65535

If you want to have access to the failure actions flag, we can add 2 new methods similar to, for example:

a@spot:~/src/golang.org/x/sys/windows/svc/mgr$ GOOS=windows go doc Service.SetRebootMessage                           
package mgr // import "."

func (s *Service) SetRebootMessage(msg string) error
    SetRebootMessage sets service s reboot message. If msg is "", the reboot
    message is deleted and no message is broadcast.

a@spot:~/src/golang.org/x/sys/windows/svc/mgr$ GOOS=windows go doc Service.RebootMessage
package mgr // import "."

func (s *Service) RebootMessage() (string, error)
    RebootMessage is broadcast to server users before rebooting in response to
    the ComputerReboot service controller action.

a@spot:~/src/golang.org/x/sys/windows/svc/mgr$

Would that work for you?

I did not need this functionality ever. But others contributed code for whatever service parameters they required. I doubt we could support all combinations that are supported by ChangeServiceConfig2 in a general and simple way. So I expect some users to call windows.ChangeServiceConfig2 directly. But it would be nice to have most common parameters supported.

Alex

[craig65535]

@alexbrainman Yes, that sounds perfect.

[alexbrainman]

@alexbrainman Yes, that sounds perfect.

Would you like to try to add that code yourself?

Alex

[craig65535]

Sure, I can give this one a shot as well.

[craig65535]

golang/sys#157

[gopherbot]

Change https://go.dev/cl/484896 mentions this issue: windows/svc/mgr: add Service.RecoveryActionsOnNonCrashFailures

[alexbrainman]

I propose to add these two methods

// SetRecoveryActionsOnNonCrashFailures sets the failure actions flag. If the
// flag is set to false, recovery actions will only be performed if the service
// terminates without reporting a status of SERVICE_STOPPED. If the flag is set
// to true, recovery actions are also perfomed if the service stops with a
// nonzero exit code.
func (s *Service) SetRecoveryActionsOnNonCrashFailures(flag bool) error


// RecoveryActionsOnNonCrashFailures returns the current value of the failure
// actions flag. If the flag is set to false, recovery actions will only be
// performed if the service terminates without reporting a status of
// SERVICE_STOPPED. If the flag is set to true, recovery actions are also
// perfomed if the service stops with a nonzero exit code.
func (s *Service) RecoveryActionsOnNonCrashFailures() (bool, error)

to the golang.org/x/sys/windows/svc/mgr.Service struct. New methods will allow users set and read SERVICE_FAILURE_ACTIONS_FLAG for the service.

We already have similar Service.RebootMessage / Service.SetRebootMessage, Service.RecoveryActions / Service.SetRecoveryActions and few others.

It is possible to achieve this functionality by calling Windows API directly. See #59016 (comment) for an example. But we decided since we already have similar attributes handled, maybe we can add RecoveryActionsOnNonCrashFailures flag to that list.

Thank you for consideration.

Alex