fake.go

/*
   Copyright 2014 CoreOS, Inc.

   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 registry

import (
	"errors"
	"sort"
	"sync"
	"time"

	"github.com/coreos/fleet/Godeps/_workspace/src/github.com/coreos/go-semver/semver"

	"github.com/coreos/fleet/job"
	"github.com/coreos/fleet/machine"
	"github.com/coreos/fleet/unit"
)

func NewFakeRegistry() *FakeRegistry {
	return &FakeRegistry{
		machines:      []machine.MachineState{},
		jobStates:     map[string]map[string]*unit.UnitState{},
		jobs:          map[string]job.Job{},
		daemonVersion: nil,
	}
}

type FakeRegistry struct {
	// Not all methods required by the Registry interface are implemented
	// by the FakeRegistry. Any calls to these unimplemented methods will
	// result in a panic.
	Registry
	sync.RWMutex

	machines      []machine.MachineState
	jobStates     map[string]map[string]*unit.UnitState
	jobs          map[string]job.Job
	daemonVersion *semver.Version
}

func (f *FakeRegistry) SetMachines(machines []machine.MachineState) {
	f.Lock()
	defer f.Unlock()

	f.machines = machines
}

func (f *FakeRegistry) SetJobs(jobs []job.Job) {
	f.Lock()
	defer f.Unlock()

	f.jobs = make(map[string]job.Job, len(jobs))
	for _, j := range jobs {
		f.jobs[j.Name] = j
	}
}

func (f *FakeRegistry) SetUnitStates(states []unit.UnitState) {
	f.Lock()
	defer f.Unlock()

	f.jobStates = make(map[string]map[string]*unit.UnitState)
	for _, us := range states {
		us := us
		name := us.UnitName
		if _, ok := f.jobStates[name]; !ok {
			f.jobStates[name] = make(map[string]*unit.UnitState)
		}
		f.jobStates[name][us.MachineID] = &us
	}
}

func (f *FakeRegistry) Machines() ([]machine.MachineState, error) {
	f.RLock()
	defer f.RUnlock()

	return f.machines, nil
}

func (f *FakeRegistry) Units() ([]job.Unit, error) {
	f.RLock()
	defer f.RUnlock()

	var sorted sort.StringSlice
	for _, j := range f.jobs {
		sorted = append(sorted, j.Name)
	}
	sorted.Sort()

	units := make([]job.Unit, len(f.jobs))
	for i, jName := range sorted {
		j := f.jobs[jName]
		u := job.Unit{
			Name:        j.Name,
			Unit:        j.Unit,
			TargetState: j.TargetState,
		}
		units[i] = u
	}

	return units, nil
}

func (f *FakeRegistry) Schedule() ([]job.ScheduledUnit, error) {
	f.RLock()
	defer f.RUnlock()

	var sorted sort.StringSlice
	for _, j := range f.jobs {
		sorted = append(sorted, j.Name)
	}
	sorted.Sort()

	sUnits := make([]job.ScheduledUnit, 0, len(f.jobs))
	for _, jName := range sorted {
		j := f.jobs[jName]
		su := job.ScheduledUnit{
			Name:            j.Name,
			State:           j.State,
			TargetMachineID: j.TargetMachineID,
		}
		sUnits = append(sUnits, su)
	}

	return sUnits, nil
}

func (f *FakeRegistry) Unit(name string) (*job.Unit, error) {
	f.RLock()
	defer f.RUnlock()

	j, ok := f.jobs[name]
	if !ok {
		return nil, nil
	}

	u := job.Unit{
		Name:        j.Name,
		Unit:        j.Unit,
		TargetState: j.TargetState,
	}
	return &u, nil
}

func (f *FakeRegistry) ScheduledUnit(name string) (*job.ScheduledUnit, error) {
	f.RLock()
	defer f.RUnlock()

	j, ok := f.jobs[name]
	if !ok {
		return nil, nil
	}

	su := job.ScheduledUnit{
		Name:            j.Name,
		State:           j.State,
		TargetMachineID: j.TargetMachineID,
	}
	return &su, nil
}

func (f *FakeRegistry) CreateUnit(u *job.Unit) error {
	f.Lock()
	defer f.Unlock()

	_, ok := f.jobs[u.Name]
	if ok {
		return errors.New("unit already exists")
	}

	j := job.Job{
		Name: u.Name,
		Unit: u.Unit,
	}

	f.jobs[u.Name] = j
	return f.unsafeSetUnitTargetState(u.Name, u.TargetState)
}

func (f *FakeRegistry) DestroyUnit(name string) error {
	f.Lock()
	defer f.Unlock()

	delete(f.jobs, name)
	return nil
}

func (f *FakeRegistry) SetUnitTargetState(name string, target job.JobState) error {
	f.Lock()
	defer f.Unlock()

	return f.unsafeSetUnitTargetState(name, target)
}

func (f *FakeRegistry) unsafeSetUnitTargetState(name string, target job.JobState) error {
	j, ok := f.jobs[name]

	if !ok {
		return errors.New("job does not exist")
	}

	j.TargetState = target
	f.jobs[name] = j

	return nil
}

func (f *FakeRegistry) ScheduleUnit(name string, machID string) error {
	f.Lock()
	defer f.Unlock()

	j, ok := f.jobs[name]

	if !ok {
		return errors.New("unit does not exist")
	}

	j.TargetMachineID = machID
	f.jobs[name] = j

	return nil
}

func (f *FakeRegistry) SaveUnitState(jobName string, unitState *unit.UnitState, ttl time.Duration) {
	f.Lock()
	defer f.Unlock()

	if _, ok := f.jobStates[jobName]; !ok {
		f.jobStates[jobName] = make(map[string]*unit.UnitState)
	}
	f.jobStates[jobName][unitState.MachineID] = unitState
}

func (f *FakeRegistry) RemoveUnitState(jobName string) error {
	delete(f.jobStates, jobName)
	return nil
}

func (f *FakeRegistry) UnitStates() ([]*unit.UnitState, error) {
	f.Lock()
	defer f.Unlock()

	states := make([]*unit.UnitState, 0)

	// Sort by unit name, then by machineID
	sUnitNames := make([]string, 0)
	for name := range f.jobStates {
		sUnitNames = append(sUnitNames, name)
	}
	sort.Strings(sUnitNames)

	for _, name := range sUnitNames {
		sMIDs := make([]string, 0)
		for machineID := range f.jobStates[name] {
			sMIDs = append(sMIDs, machineID)
		}
		sort.Strings(sMIDs)
		for _, mID := range sMIDs {
			states = append(states, f.jobStates[name][mID])
		}
	}
	return states, nil
}

func (f *FakeRegistry) UnitHeartbeat(name, machID string, ttl time.Duration) error {
	return nil
}

func (f *FakeRegistry) ClearUnitHeartbeat(string) {}

func NewFakeClusterRegistry(dVersion *semver.Version, eVersion int) *FakeClusterRegistry {
	return &FakeClusterRegistry{
		dVersion: dVersion,
		eVersion: eVersion,
	}
}

type FakeClusterRegistry struct {
	dVersion *semver.Version
	eVersion int
}

func (fc *FakeClusterRegistry) LatestDaemonVersion() (*semver.Version, error) {
	return fc.dVersion, nil
}

func (fc *FakeClusterRegistry) EngineVersion() (int, error) {
	return fc.eVersion, nil
}

func (fc *FakeClusterRegistry) UpdateEngineVersion(from, to int) error {
	if fc.eVersion != from {
		return errors.New("version mismatch")
	}

	fc.eVersion = to
	return nil
}

func (fl *FakeLeaseRegistry) SetLease(name, machID string, ver int, ttl time.Duration) *fakeLease {
	l := &fakeLease{
		name:   name,
		machID: machID,
		ver:    ver,
		ttl:    ttl,
		reg:    fl,
	}

	fl.leaseMap[name] = l
	return l
}

type fakeLease struct {
	name   string
	machID string
	ver    int
	ttl    time.Duration
	reg    *FakeLeaseRegistry
}

func (l *fakeLease) MachineID() string {
	return l.machID
}

func (l *fakeLease) Version() int {
	return l.ver
}

func (l *fakeLease) TimeRemaining() time.Duration {
	return l.ttl
}

func (l *fakeLease) Index() uint64 {
	return 0
}

func (l *fakeLease) Renew(ttl time.Duration) error {
	if l.reg == nil {
		return errors.New("already released")
	}

	l.ttl = ttl
	return nil
}

func (l *fakeLease) Release() error {
	if l.reg == nil {
		return errors.New("already released")
	}

	delete(l.reg.leaseMap, l.name)
	l.reg = nil
	return nil
}

func NewFakeLeaseRegistry() *FakeLeaseRegistry {
	return &FakeLeaseRegistry{
		leaseMap: make(map[string]Lease),
	}
}

type FakeLeaseRegistry struct {
	leaseMap map[string]Lease
}

func (fl *FakeLeaseRegistry) GetLease(name string) (Lease, error) {
	return fl.leaseMap[name], nil
}

func (fl *FakeLeaseRegistry) AcquireLease(name, machID string, ver int, ttl time.Duration) (Lease, error) {
	if _, ok := fl.leaseMap[name]; ok {
		return nil, errors.New("already exists")
	}

	l := &fakeLease{
		name:   name,
		machID: machID,
		ver:    ver,
		ttl:    ttl,
		reg:    fl,
	}

	fl.leaseMap[name] = l
	return l, nil
}

func (fl *FakeLeaseRegistry) StealLease(name, machID string, ver int, ttl time.Duration, idx uint64) (Lease, error) {
	if idx != 0 {
		panic("unable to test StealLease with index other than zero")
	}

	_, ok := fl.leaseMap[name]
	if !ok {
		return nil, errors.New("does not exist")
	}

	l := &fakeLease{
		name:   name,
		machID: machID,
		ver:    ver,
		ttl:    ttl,
		reg:    fl,
	}

	fl.leaseMap[name] = l
	return l, nil
}