open-nomad/client/allocrunner/upstream_allocs_hook.go
2018-12-11 13:12:35 +01:00

33 lines
803 B
Go

package allocrunner
import (
"context"
log "github.com/hashicorp/go-hclog"
"github.com/hashicorp/nomad/client/allocwatcher"
)
// upstreamAllocsHook waits for a PrevAllocWatcher to exit before allowing
// an allocation to be executed
type upstreamAllocsHook struct {
allocWatcher allocwatcher.PrevAllocWatcher
logger log.Logger
}
func newUpstreamAllocsHook(logger log.Logger, allocWatcher allocwatcher.PrevAllocWatcher) *upstreamAllocsHook {
h := &upstreamAllocsHook{
allocWatcher: allocWatcher,
}
h.logger = logger.Named(h.Name())
return h
}
func (h *upstreamAllocsHook) Name() string {
return "await_previous_allocations"
}
func (h *upstreamAllocsHook) Prerun(ctx context.Context) error {
// Wait for a previous alloc - if any - to terminate
return h.allocWatcher.Wait(ctx)
}