zrepl/daemon/job/build_jobs.go
Christian Schwarz f5f269bfd5 send/recv: job-level bandwidth limiting
Sponsored-by: Prominic.NET, Inc.

fixes #339
2021-09-12 20:08:43 +02:00

121 lines
3.0 KiB
Go

package job
import (
"fmt"
"sort"
"strings"
"github.com/pkg/errors"
"github.com/zrepl/zrepl/config"
"github.com/zrepl/zrepl/util/bandwidthlimit"
)
func JobsFromConfig(c *config.Config) ([]Job, error) {
js := make([]Job, len(c.Jobs))
for i := range c.Jobs {
j, err := buildJob(c.Global, c.Jobs[i])
if err != nil {
return nil, err
}
if j == nil || j.Name() == "" {
panic(fmt.Sprintf("implementation error: job builder returned nil job type %T", c.Jobs[i].Ret))
}
js[i] = j
}
// receiving-side root filesystems must not overlap
{
rfss := make([]string, 0, len(js))
for _, j := range js {
jrfs, ok := j.OwnedDatasetSubtreeRoot()
if !ok {
continue
}
rfss = append(rfss, jrfs.ToString())
}
if err := validateReceivingSidesDoNotOverlap(rfss); err != nil {
return nil, err
}
}
return js, nil
}
func buildJob(c *config.Global, in config.JobEnum) (j Job, err error) {
cannotBuildJob := func(e error, name string) (Job, error) {
return nil, errors.Wrapf(e, "cannot build job %q", name)
}
// FIXME prettify this
switch v := in.Ret.(type) {
case *config.SinkJob:
j, err = passiveSideFromConfig(c, &v.PassiveJob, v)
if err != nil {
return cannotBuildJob(err, v.Name)
}
case *config.SourceJob:
j, err = passiveSideFromConfig(c, &v.PassiveJob, v)
if err != nil {
return cannotBuildJob(err, v.Name)
}
case *config.SnapJob:
j, err = snapJobFromConfig(c, v)
if err != nil {
return cannotBuildJob(err, v.Name)
}
case *config.PushJob:
j, err = activeSide(c, &v.ActiveJob, v)
if err != nil {
return cannotBuildJob(err, v.Name)
}
case *config.PullJob:
j, err = activeSide(c, &v.ActiveJob, v)
if err != nil {
return cannotBuildJob(err, v.Name)
}
default:
panic(fmt.Sprintf("implementation error: unknown job type %T", v))
}
return j, nil
}
func validateReceivingSidesDoNotOverlap(receivingRootFSs []string) error {
if len(receivingRootFSs) == 0 {
return nil
}
rfss := make([]string, len(receivingRootFSs))
copy(rfss, receivingRootFSs)
sort.Slice(rfss, func(i, j int) bool {
return strings.Compare(rfss[i], rfss[j]) == -1
})
// add tailing slash because of hierarchy-simulation
// rootfs/ is not root of rootfs2/
for i := 0; i < len(rfss); i++ {
rfss[i] += "/"
}
// idea:
// no path in rfss must be prefix of another
//
// rfss is now lexicographically sorted, which means that
// if i is prefix of j, i < j (in lexicographical order)
// thus,
// if any i is prefix of i+n (n >= 1), there is overlap
for i := 0; i < len(rfss)-1; i++ {
if strings.HasPrefix(rfss[i+1], rfss[i]) {
return fmt.Errorf("receiving jobs with overlapping root filesystems are forbidden")
}
}
return nil
}
func buildBandwidthLimitConfig(in *config.BandwidthLimit) (c bandwidthlimit.Config, _ error) {
if in.Max.ToBytes() > 0 && int64(in.Max.ToBytes()) == 0 {
return c, fmt.Errorf("bandwidth limit `max` is too small, must at least specify one byte")
}
return bandwidthlimit.Config{
Max: int64(in.Max.ToBytes()),
BucketCapacity: int64(in.BucketCapacity.ToBytes()),
}, nil
}