harbor/job/statemachine.go
2016-07-05 11:42:30 +08:00

299 lines
9.9 KiB
Go

/*
Copyright (c) 2016 VMware, Inc. All Rights Reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package job
import (
"fmt"
"sync"
"github.com/vmware/harbor/dao"
"github.com/vmware/harbor/job/config"
"github.com/vmware/harbor/job/replication"
"github.com/vmware/harbor/job/utils"
"github.com/vmware/harbor/models"
uti "github.com/vmware/harbor/utils"
"github.com/vmware/harbor/utils/log"
)
// RepJobParm wraps the parm of a job
type RepJobParm struct {
LocalRegURL string
TargetURL string
TargetUsername string
TargetPassword string
Repository string
Tags []string
Enabled int
Operation string
Insecure bool
}
// SM is the state machine to handle job, it handles one job at a time.
type SM struct {
JobID int64
CurrentState string
PreviousState string
//The states that don't have to exist in transition map, such as "Error", "Canceled"
ForcedStates map[string]struct{}
Transitions map[string]map[string]struct{}
Handlers map[string]StateHandler
desiredState string
Logger *log.Logger
Parms *RepJobParm
lock *sync.Mutex
}
// EnterState transit the statemachine from the current state to the state in parameter.
// It returns the next state the statemachine should tranit to.
func (sm *SM) EnterState(s string) (string, error) {
log.Debugf("Job id: %d, transiting from State: %s, to State: %s", sm.JobID, sm.CurrentState, s)
targets, ok := sm.Transitions[sm.CurrentState]
_, exist := targets[s]
_, isForced := sm.ForcedStates[s]
if !exist && !isForced {
return "", fmt.Errorf("Job id: %d, transition from %s to %s does not exist!", sm.JobID, sm.CurrentState, s)
}
exitHandler, ok := sm.Handlers[sm.CurrentState]
if ok {
if err := exitHandler.Exit(); err != nil {
return "", err
}
} else {
log.Debugf("Job id: %d, no handler found for state:%s, skip", sm.JobID, sm.CurrentState)
}
enterHandler, ok := sm.Handlers[s]
var next = models.JobContinue
var err error
if ok {
if next, err = enterHandler.Enter(); err != nil {
return "", err
}
} else {
log.Debugf("Job id: %d, no handler found for state:%s, skip", sm.JobID, s)
}
sm.PreviousState = sm.CurrentState
sm.CurrentState = s
log.Debugf("Job id: %d, transition succeeded, current state: %s", sm.JobID, s)
return next, nil
}
// Start kicks off the statemachine to transit from current state to s, and moves on
// It will search the transit map if the next state is "_continue", and
// will enter error state if there's more than one possible path when next state is "_continue"
func (sm *SM) Start(s string) {
n, err := sm.EnterState(s)
log.Debugf("Job id: %d, next state from handler: %s", sm.JobID, n)
for len(n) > 0 && err == nil {
if d := sm.getDesiredState(); len(d) > 0 {
log.Debugf("Job id: %d. Desired state: %s, will ignore the next state from handler", sm.JobID, d)
n = d
sm.setDesiredState("")
continue
}
if n == models.JobContinue && len(sm.Transitions[sm.CurrentState]) == 1 {
for n = range sm.Transitions[sm.CurrentState] {
break
}
log.Debugf("Job id: %d, Continue to state: %s", sm.JobID, n)
continue
}
if n == models.JobContinue && len(sm.Transitions[sm.CurrentState]) != 1 {
log.Errorf("Job id: %d, next state is continue but there are %d possible next states in transition table", sm.JobID, len(sm.Transitions[sm.CurrentState]))
err = fmt.Errorf("Unable to continue")
break
}
n, err = sm.EnterState(n)
log.Debugf("Job id: %d, next state from handler: %s", sm.JobID, n)
}
if err != nil {
log.Warningf("Job id: %d, the statemachin will enter error state due to error: %v", sm.JobID, err)
sm.EnterState(models.JobError)
}
}
// AddTransition add a transition to the transition table of state machine, the handler is the handler of target state "to"
func (sm *SM) AddTransition(from string, to string, h StateHandler) {
_, ok := sm.Transitions[from]
if !ok {
sm.Transitions[from] = make(map[string]struct{})
}
sm.Transitions[from][to] = struct{}{}
sm.Handlers[to] = h
}
// RemoveTransition removes a transition from transition table of the state machine
func (sm *SM) RemoveTransition(from string, to string) {
_, ok := sm.Transitions[from]
if !ok {
return
}
delete(sm.Transitions[from], to)
}
// Stop will set the desired state as "stopped" such that when next tranisition happen the state machine will stop handling the current job
// and the worker can release itself to the workerpool.
func (sm *SM) Stop(id int64) {
log.Debugf("Trying to stop the job: %d", id)
sm.lock.Lock()
defer sm.lock.Unlock()
//need to check if the sm switched to other job
if id == sm.JobID {
sm.desiredState = models.JobStopped
log.Debugf("Desired state of job %d is set to stopped", id)
} else {
log.Debugf("State machine has switched to job %d, so the action to stop job %d will be ignored", sm.JobID, id)
}
}
func (sm *SM) getDesiredState() string {
sm.lock.Lock()
defer sm.lock.Unlock()
return sm.desiredState
}
func (sm *SM) setDesiredState(s string) {
sm.lock.Lock()
defer sm.lock.Unlock()
sm.desiredState = s
}
// Init initialzie the state machine, it will be called once in the lifecycle of state machine.
func (sm *SM) Init() {
sm.lock = &sync.Mutex{}
sm.Handlers = make(map[string]StateHandler)
sm.Transitions = make(map[string]map[string]struct{})
sm.ForcedStates = map[string]struct{}{
models.JobError: struct{}{},
models.JobStopped: struct{}{},
models.JobCanceled: struct{}{},
models.JobRetrying: struct{}{},
}
}
// Reset resets the state machine so it will start handling another job.
func (sm *SM) Reset(jid int64) error {
//To ensure the new jobID is visible to the thread to stop the SM
sm.lock.Lock()
sm.JobID = jid
sm.desiredState = ""
sm.lock.Unlock()
//init parms
job, err := dao.GetRepJob(sm.JobID)
if err != nil {
return fmt.Errorf("Failed to get job, error: %v", err)
}
if job == nil {
return fmt.Errorf("The job doesn't exist in DB, job id: %d", sm.JobID)
}
policy, err := dao.GetRepPolicy(job.PolicyID)
if err != nil {
return fmt.Errorf("Failed to get policy, error: %v", err)
}
if policy == nil {
return fmt.Errorf("The policy doesn't exist in DB, policy id:%d", job.PolicyID)
}
sm.Parms = &RepJobParm{
LocalRegURL: config.LocalRegURL(),
Repository: job.Repository,
Tags: job.TagList,
Enabled: policy.Enabled,
Operation: job.Operation,
Insecure: !config.VerifyRemoteCert(),
}
if policy.Enabled == 0 {
//worker will cancel this job
return nil
}
target, err := dao.GetRepTarget(policy.TargetID)
if err != nil {
return fmt.Errorf("Failed to get target, error: %v", err)
}
if target == nil {
return fmt.Errorf("The target doesn't exist in DB, target id: %d", policy.TargetID)
}
sm.Parms.TargetURL = target.URL
sm.Parms.TargetUsername = target.Username
pwd := target.Password
if len(pwd) != 0 {
pwd, err = uti.ReversibleDecrypt(pwd)
if err != nil {
return fmt.Errorf("failed to decrypt password: %v", err)
}
}
sm.Parms.TargetPassword = pwd
//init states handlers
sm.Logger = utils.NewLogger(sm.JobID)
sm.Handlers = make(map[string]StateHandler)
sm.Transitions = make(map[string]map[string]struct{})
sm.CurrentState = models.JobPending
sm.AddTransition(models.JobPending, models.JobRunning, StatusUpdater{sm.JobID, models.JobRunning})
sm.AddTransition(models.JobRetrying, models.JobRunning, StatusUpdater{sm.JobID, models.JobRunning})
sm.Handlers[models.JobError] = StatusUpdater{sm.JobID, models.JobError}
sm.Handlers[models.JobStopped] = StatusUpdater{sm.JobID, models.JobStopped}
sm.Handlers[models.JobRetrying] = Retry{sm.JobID}
switch sm.Parms.Operation {
case models.RepOpTransfer:
err = addImgTransferTransition(sm)
case models.RepOpDelete:
err = addImgDeleteTransition(sm)
default:
err = fmt.Errorf("unsupported operation: %s", sm.Parms.Operation)
}
return err
}
//for testing onlly
func addTestTransition(sm *SM) error {
sm.AddTransition(models.JobRunning, "pull-img", ImgPuller{img: sm.Parms.Repository, logger: sm.Logger})
return nil
}
func addImgTransferTransition(sm *SM) error {
base, err := replication.InitBaseHandler(sm.Parms.Repository, sm.Parms.LocalRegURL, config.UISecret(),
sm.Parms.TargetURL, sm.Parms.TargetUsername, sm.Parms.TargetPassword,
sm.Parms.Insecure, sm.Parms.Tags, sm.Logger)
if err != nil {
return err
}
sm.AddTransition(models.JobRunning, replication.StateCheck, &replication.Checker{BaseHandler: base})
sm.AddTransition(replication.StateCheck, replication.StatePullManifest, &replication.ManifestPuller{BaseHandler: base})
sm.AddTransition(replication.StatePullManifest, replication.StateTransferBlob, &replication.BlobTransfer{BaseHandler: base})
sm.AddTransition(replication.StatePullManifest, models.JobFinished, &StatusUpdater{sm.JobID, models.JobFinished})
sm.AddTransition(replication.StateTransferBlob, replication.StatePushManifest, &replication.ManifestPusher{BaseHandler: base})
sm.AddTransition(replication.StatePushManifest, replication.StatePullManifest, &replication.ManifestPuller{BaseHandler: base})
return nil
}
func addImgDeleteTransition(sm *SM) error {
deleter, err := replication.NewDeleter(sm.Parms.Repository, sm.Parms.Tags, sm.Parms.TargetURL,
sm.Parms.TargetUsername, sm.Parms.TargetPassword, sm.Parms.Insecure, sm.Logger)
if err != nil {
return err
}
sm.AddTransition(models.JobRunning, replication.StateDelete, deleter)
sm.AddTransition(replication.StateDelete, models.JobFinished, &StatusUpdater{sm.JobID, models.JobFinished})
return nil
}