manual

type Resolver struct {
	// BuildCallback is called when the Build method is called.  Must not be
	// nil.  Must not be changed after the resolver may be built.
	BuildCallback func(resolver.Target, resolver.ClientConn, resolver.BuildOptions)
	// UpdateStateCallback is called when the UpdateState method is called on
	// the resolver.  The value passed as argument to this callback is the value
	// returned by the resolver.ClientConn.  Must not be nil.  Must not be
	// changed after the resolver may be built.
	UpdateStateCallback func(err error)
	// ResolveNowCallback is called when the ResolveNow method is called on the
	// resolver.  Must not be nil.  Must not be changed after the resolver may
	// be built.
	ResolveNowCallback func(resolver.ResolveNowOptions)
	// CloseCallback is called when the Close method is called.  Must not be
	// nil.  Must not be changed after the resolver may be built.
	CloseCallback func()

	CC resolver.ClientConn
	// contains filtered or unexported fields
}