Newer
Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
//
// Copyright 2023 Bytedance Ltd. and/or its affiliates
//
// 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 dddfirework
import (
"context"
"encoding/json"
"errors"
"fmt"
stdlog "log"
"os"
"reflect"
"sort"
"strings"
"github.com/go-logr/logr"
"github.com/go-logr/stdr"
"github.com/rs/xid"
)
var ErrBreak = fmt.Errorf("break process") // 中断流程,不返回错误
var ErrEntityNotFound = fmt.Errorf("entity not found")
var ErrEntityRepeated = fmt.Errorf("entity already added")
var defaultLogger = stdr.New(stdlog.New(os.Stderr, "", stdlog.LstdFlags|stdlog.Lshortfile)).WithName("ddd_engine")
type ILock interface {
Lock(ctx context.Context, key string) (keyLock interface{}, err error)
UnLock(ctx context.Context, keyLock interface{}) error
}
type IIDGenerator interface {
NewID() (string, error)
}
type defaultIDGenerator struct {
}
func (d *defaultIDGenerator) NewID() (string, error) {
guid := xid.New()
return guid.String(), nil
}
// EntityContainer 负责维护领域内所有聚合根实体的实体
type EntityContainer struct {
BaseEntity
roots []IEntity // 保存聚合根实体
deleted []IEntity // 保存所有被删除实体
}
func (w *EntityContainer) GetChildren() map[string][]IEntity {
return map[string][]IEntity{"meta": w.roots}
}
func (w *EntityContainer) GetDeleted() []IEntity {
return w.deleted
}
func (w *EntityContainer) SetChildren(roots []IEntity) {
// EntityContainer 里面会有修改 roots 的操作,应当拷贝一个新的 slice,隔离输入的影响
w.roots = make([]IEntity, len(roots))
copy(w.roots, roots)
}
func (w *EntityContainer) Add(root IEntity) error {
for _, e := range w.roots {
if e == root {
return ErrEntityRepeated
}
}
w.roots = append(w.roots, root)
return nil
}
func (w *EntityContainer) Remove(root IEntity) error {
i := 0
for _, item := range w.roots {
if item != root {
w.roots[i] = item
i++
}
}
if i == len(w.roots) {
return ErrEntityNotFound
}
w.roots = w.roots[:i]
w.deleted = append(w.deleted, root)
return nil
}
// Recycle 回收所有被删除的实体
func (w *EntityContainer) Recycle(e IEntity) {
w.deleted = append(w.deleted, e)
}
type ErrList []error
func (e ErrList) Error() string {
errs := make([]string, 0)
for _, err := range e {
errs = append(errs, err.Error())
}
return strings.Join(errs, ", ")
}
type Result struct {
Error error
Break bool
Actions []*Action
Output interface{}
}
func ResultErrors(err ...error) *Result {
return &Result{Error: ErrList(err)}
}
func ResultError(err error) *Result {
return &Result{Error: err}
}
func ResultErrOrBreak(err error) *Result {
if errors.Is(err, ErrBreak) {
return &Result{Break: true}
}
return ResultError(err)
}
type DomainBuilder struct {
stage *Stage
}
// Build 查询并构建 parent 以及 children 实体
// parent 必须指定 id,children 为可选,需要是 *IEntity 或者 *[]IEntity 类型
func (h DomainBuilder) Build(ctx context.Context, parent IEntity, children ...interface{}) error {
return h.stage.BuildEntity(ctx, parent, children...)
}
// RootContainer 聚合根实体容器
type RootContainer struct {
stage *Stage
errs []error
}
// Add 创建聚合根实体
func (h *RootContainer) Add(root IEntity) {
if err := h.stage.meta.Add(root); err != nil {
h.errs = append(h.errs, err)
}
}
// Remove 删除聚合根实体
func (h *RootContainer) Remove(root IEntity) {
if err := h.stage.meta.Remove(root); err != nil {
h.errs = append(h.errs, err)
}
}
type BuildFunc func(ctx context.Context, h DomainBuilder) (roots []IEntity, err error)
type ActFunc func(ctx context.Context, container RootContainer, roots ...IEntity) error
type PostSaveFunc func(ctx context.Context, res *Result)
// EventHandlerConstruct EventHandler 的构造函数,带一个入参和一个返回值,入参是与事件类型匹配的事件数据指针类型,返回值是 ICommand
// 示例 func(evt *OrderCreatedEvent) *OnEventCreateCommand
type EventHandlerConstruct interface{}
type Options struct {
WithTransaction bool
RecursiveDelete bool // 删除根实体是否递归删除所有子实体
EventPersist EventPersist // 是否保存领域事件到 DB
Logger logr.Logger
EventBus IEventBus
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
IDGenerator IIDGenerator
PostSaveHooks []PostSaveFunc
}
type Option interface {
ApplyToOptions(*Options)
}
type TransactionOption bool
func (t TransactionOption) ApplyToOptions(opts *Options) {
opts.WithTransaction = bool(t)
}
const WithTransaction = TransactionOption(true)
const WithoutTransaction = TransactionOption(false)
type RecursiveDeleteOption bool
func (t RecursiveDeleteOption) ApplyToOptions(opts *Options) {
opts.RecursiveDelete = bool(t)
}
const WithRecursiveDelete = RecursiveDeleteOption(true)
type LoggerOption struct {
logger logr.Logger
}
func (t LoggerOption) ApplyToOptions(opts *Options) {
opts.Logger = t.logger
}
func WithLogger(logger logr.Logger) LoggerOption {
return LoggerOption{logger: logger}
}
type EventBusOption struct {
eventBus IEventBus
}
func (t EventBusOption) ApplyToOptions(opts *Options) {
opts.EventBus = t.eventBus
}
func WithEventBus(eventBus IEventBus) EventBusOption {
return EventBusOption{eventBus: eventBus}
}
type DTimerOption struct {
timer ITimer
}
func (t DTimerOption) ApplyToOptions(opts *Options) {
opts.Timer = t.timer
}
func WithTimer(timer ITimer) DTimerOption {
return DTimerOption{timer: timer}
}
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
type EventPersist func(event *DomainEvent) (IModel, error)
type EventSaveOption EventPersist
func (t EventSaveOption) ApplyToOptions(opts *Options) {
opts.EventPersist = EventPersist(t)
}
func WithEventPersist(f EventPersist) EventSaveOption {
return EventSaveOption(f)
}
type IDGeneratorOption struct {
idGen IIDGenerator
}
func (t IDGeneratorOption) ApplyToOptions(opts *Options) {
opts.IDGenerator = t.idGen
}
func WithIDGenerator(idGen IIDGenerator) IDGeneratorOption {
return IDGeneratorOption{idGen: idGen}
}
type PostSaveOption PostSaveFunc
func (t PostSaveOption) ApplyToOptions(opts *Options) {
opts.PostSaveHooks = append(opts.PostSaveHooks, PostSaveFunc(t))
}
func WithPostSave(f PostSaveFunc) PostSaveOption {
return PostSaveOption(f)
}
type Engine struct {
locker ILock
executor IExecutor
idGenerator IIDGenerator
eventbus IEventBus
logger logr.Logger
options Options
}
func NewEngine(l ILock, e IExecutor, opts ...Option) *Engine {
options := Options{
// 默认开启事务
WithTransaction: true,
Logger: defaultLogger,
IDGenerator: &defaultIDGenerator{},
EventBus: &noEventBus{},
}
for _, opt := range opts {
opt.ApplyToOptions(&options)
}
eventBus := options.EventBus
eventBus.RegisterEventHandler(onEvent)
if txEB, ok := eventBus.(ITransactionEventBus); ok {
txEB.RegisterEventTXChecker(onTXChecker)
}
timer := options.Timer
timer.RegisterTimerHandler(onTimer)
return &Engine{
locker: l,
executor: e,
eventbus: eventBus,
options: options,
logger: options.Logger,
idGenerator: options.IDGenerator,
}
}
func (e *Engine) NewStage() *Stage {
return &Stage{
locker: e.locker,
executor: e.executor,
eventBus: e.eventbus,
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
idGenerator: e.idGenerator,
meta: &EntityContainer{},
result: &Result{},
options: e.options,
logger: e.logger,
}
}
func (e *Engine) Create(ctx context.Context, roots ...IEntity) *Result {
return e.NewStage().Act(func(ctx context.Context, container RootContainer, entities ...IEntity) error {
for _, r := range roots {
container.Add(r)
}
return nil
}).Save(ctx)
}
func (e *Engine) Delete(ctx context.Context, roots ...IEntity) *Result {
return e.NewStage().Build(func(ctx context.Context, builder DomainBuilder) ([]IEntity, error) {
return roots, nil
}).Act(func(ctx context.Context, container RootContainer, roots ...IEntity) error {
for _, r := range roots {
container.Remove(r)
}
return nil
}).Save(ctx)
}
func (e *Engine) RunCommand(ctx context.Context, c ICommand, opts ...Option) *Result {
return e.NewStage().WithOption(opts...).RunCommand(ctx, c)
}
func (e *Engine) RegisterEventHandler(eventType EventType, construct EventHandlerConstruct) {
handlerType := reflect.TypeOf(construct)
if handlerType.Kind() != reflect.Func {
panic("construct must type of reflect.Func")
}
if handlerType.NumIn() != 1 || handlerType.NumOut() != 1 {
panic("construct num of arg or output must 1")
}
evtType := handlerType.In(0)
if evtType.Kind() != reflect.Ptr {
panic("event type must be pointer")
}
evtType = evtType.Elem() // event type 引用实际类型
outType := handlerType.Out(0)
if !outType.Implements(cmdType) {
panic("construct output must be type of ICommand")
}
constructFunc := reflect.ValueOf(construct)
RegisterEventHandler(eventType, func(ctx context.Context, evt *DomainEvent) error {
var bizEvt reflect.Value
if evtType == domainEventType {
bizEvt = reflect.ValueOf(evt)
} else {
bizEvt = reflect.New(evtType)
if err := json.Unmarshal(evt.Payload, bizEvt.Interface()); err != nil {
e.logger.Error(err, "unmarshal event failed")
return err
}
}
outputs := constructFunc.Call([]reflect.Value{bizEvt})
if res := e.RunCommand(ctx, outputs[0].Interface().(ICommand)); res.Error != nil {
e.logger.Error(res.Error, "event handler exec failed")
return res.Error
}
return nil
})
}
// RegisterCronTask 注册定时任务
func (e *Engine) RegisterCronTask(key EventType, cron string, f func(key, cron string)) {
if e.timer == nil {
panic("No ITimer specified")
}
if hasEventHandler(key) {
panic("key has registered")
}
RegisterEventHandler(key, func(ctx context.Context, evt *TimerEvent) error {
f(evt.Key, evt.Cron)
return nil
})
if err := e.timer.RunCron(string(key), cron, nil); err != nil {
panic(err)
}
}
// Stage 取舞台的意思,表示单次运行
type Stage struct {
lockKeys []string
build BuildFunc
act ActFunc
locker ILock
executor IExecutor
eventBus IEventBus
idGenerator IIDGenerator
logger logr.Logger
options Options
meta *EntityContainer
snapshot entitySnapshotPool
result *Result
eventCtx context.Context
}
func (e *Stage) WithOption(opts ...Option) *Stage {
for _, opt := range opts {
opt.ApplyToOptions(&e.options)
}
eventBus := e.options.EventBus
eventBus.RegisterEventHandler(onEvent)
if txEB, ok := eventBus.(ITransactionEventBus); ok {
txEB.RegisterEventTXChecker(onTXChecker)
}
e.eventBus = eventBus
timer := e.options.Timer
timer.RegisterTimerHandler(onTimer)
e.timer = timer
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
e.logger = e.options.Logger
e.idGenerator = e.options.IDGenerator
return e
}
func changeType2OP(t changeType) OpType {
switch t {
case newChildren:
return OpInsert
case dirtyChildren:
return OpUpdate
case deleteChildren, clearChildren:
return OpDelete
}
return OpUnknown
}
// BuildEntity 查询并构建 parent 以及 children 实体
// parent 必须指定 id,children 为可选,需要是 *IEntity 或者 *[]IEntity 类型
func (e *Stage) BuildEntity(ctx context.Context, parent IEntity, children ...interface{}) error {
if parent.GetID() == "" {
return fmt.Errorf("parent must has ID")
}
if err := e.buildEntity(ctx, parent, nil); err != nil {
return err
}
for _, item := range children {
itemType := reflect.TypeOf(item)
if itemType.Kind() != reflect.Ptr {
return fmt.Errorf("children must be pointer")
}
if itemType.Elem().Kind() == reflect.Slice {
if err := e.buildEntitySliceByParent(ctx, parent, item); err != nil {
return err
}
} else if itemType.Implements(entityType) {
if err := e.buildEntity(ctx, item.(IEntity), parent); err != nil && !errors.Is(err, ErrEntityNotFound) {
return err
}
} else {
return fmt.Errorf("children type must be IEntity")
}
}
return nil
}
// 查询并构建 entity 实体,注意,不会处理 parent 实体
func (e *Stage) buildEntity(ctx context.Context, entity, parent IEntity) error {
// 至少一个有 ID
if entity.GetID() == "" && parent.GetID() == "" {
return fmt.Errorf("entity to build must has id")
}
po, err := e.executor.Entity2Model(entity, parent, OpQuery)
if err != nil {
return err
}
posPointer := reflect.New(reflect.SliceOf(reflect.TypeOf(po)))
if err := e.executor.Exec(ctx, &Action{
Op: OpQuery,
Query: po,
QueryResult: posPointer.Interface(),
}); err != nil {
return err
}
if posPointer.Elem().Len() == 0 {
return ErrEntityNotFound
}
queryPO := posPointer.Elem().Index(0).Interface()
return e.executor.Model2Entity(queryPO.(IModel), entity)
}
func (e *Stage) buildEntitySliceByParent(ctx context.Context, parent IEntity, children interface{}) error {
childrenType := reflect.TypeOf(children)
if childrenType.Kind() != reflect.Ptr || childrenType.Elem().Kind() != reflect.Slice {
return fmt.Errorf("children must be pointer of slice")
}
eType := childrenType.Elem().Elem()
if !eType.Implements(entityType) {
return fmt.Errorf("element of children must implement IEntity")
}
if eType.Kind() == reflect.Ptr {
eType = eType.Elem()
}
entity := reflect.New(eType)
po, err := e.executor.Entity2Model(entity.Interface().(IEntity), parent, OpQuery)
if err != nil {
return err
}
posPointer := reflect.New(reflect.SliceOf(reflect.TypeOf(po)))
if err := e.executor.Exec(ctx, &Action{
Op: OpQuery,
Query: po,
QueryResult: posPointer.Interface(),
}); err != nil {
return err
}
if posPointer.Elem().Len() == 0 {
return nil
}
resultVal := reflect.ValueOf(children)
entitiesVal := resultVal.Elem()
for i := 0; i < posPointer.Elem().Len(); i++ {
newEntity := reflect.New(eType)
if err := e.executor.Model2Entity(posPointer.Elem().Index(i).Interface().(IModel), newEntity.Interface().(IEntity)); err != nil {
return err
}
entitiesVal = reflect.Append(entitiesVal, newEntity)
}
resultVal.Elem().Set(entitiesVal)
return nil
}
func (e *Stage) Lock(keys ...string) *Stage {
e.lockKeys = keys
return e
}
func (e *Stage) Build(f BuildFunc) *Stage {
e.build = f
return e
}
func (e *Stage) Act(f ActFunc) *Stage {
e.act = f
return e
}
func (e *Stage) RunCommand(ctx context.Context, c ICommand) *Result {
if setter, ok := c.(IStageSetter); ok {
setter.SetStage(StageAgent{st: e})
}
keys, err := c.Init(ctx)
if err != nil {
return ResultErrOrBreak(err)
}
return e.WithOption(PostSaveOption(c.PostSave)).Lock(keys...).Build(c.Build).Act(c.Act).Save(ctx)
}
func childrenSnapshot(children map[string][]IEntity) map[string][]IEntity {
snapshot := make(map[string][]IEntity, len(children))
for k, v := range children {
v2 := make([]IEntity, len(v))
copy(v2, v)
snapshot[k] = v2
}
return snapshot
}
func (e *Stage) makeSnapshot() error {
e.snapshot = entitySnapshotPool{}
return walk(e.meta, nil, func(entity, parent IEntity, children map[string][]IEntity) error {
if _, in := e.snapshot[entity]; in {
return nil
}
po, err := e.executor.Entity2Model(entity, parent, OpQuery)
if err != nil && !errors.Is(ErrEntityNotRegister, err) {
return err
}
e.snapshot[entity] = &entitySnapshot{
po: po,
children: childrenSnapshot(children),
}
return nil
})
}
// unDirty 对所有实体取消 Dirty 标记
func (e *Stage) unDirty() {
_ = walk(e.meta, nil, func(entity, parent IEntity, children map[string][]IEntity) error {
entity.UnDirty()
return nil
})
}
func (e *Stage) getEntityChanged() ([]*entityChanged, error) {
changed := entityDiff(e.meta, e.snapshot)
// 处理实体移动的场景
changed, err := handleEntityMove(changed)
if err != nil {
return nil, err
}
// 处理递归删除子实体
if e.options.RecursiveDelete {
changed = recursiveDelete(changed)
}
return changed, nil
}
func (e *Stage) recycle(changed []*entityChanged) {
for _, c := range changed {
if c.changeType == deleteChildren {
for _, entity := range c.children {
e.meta.Recycle(entity)
}
}
}
}
// 为新对象统一生成id
func (e *Stage) putNewID(changes []*entityChanged) error {
for _, item := range changes {
if item.changeType == newChildren {
for _, child := range item.children {
if child.GetID() == "" {
id, err := e.idGenerator.NewID()
if err != nil {
return err
}
child.SetID(id)
}
}
}
}
return nil
}
// 相同操作,相同类型的PO,合并到一个 Action
func (e *Stage) makeActions(changes []*entityChanged) ([]*Action, error) {
typeActions := make(map[OpType]map[reflect.Type]*Action, 3)
for _, item := range changes {
for _, entity := range item.children {
op := changeType2OP(item.changeType)
po, err := e.executor.Entity2Model(entity, item.parent, op)
if err != nil {
if errors.Is(err, ErrEntityNotRegister) {
e.logger.Info("entity not registered", "type", reflect.TypeOf(entity))
continue
}
return nil, err
}
poType := reflect.TypeOf(po)
if _, in := typeActions[op]; !in {
typeActions[op] = map[reflect.Type]*Action{}
}
if _, in := typeActions[op][poType]; in {
typeActions[op][poType].Models = append(typeActions[op][poType].Models, po)
} else {
typeActions[op][poType] = &Action{
Op: op,
Models: []IModel{po},
}
}
if op == OpUpdate {
typeActions[op][poType].PrevModels = append(typeActions[op][poType].PrevModels, e.snapshot[entity].po)
}
}
}
actions := make([]*Action, 0)
for _, t := range []OpType{OpInsert, OpUpdate, OpDelete} {
for _, a := range typeActions[t] {
actions = append(actions, a)
}
}
return actions, nil
}
func (e *Stage) collectEvents() []*DomainEvent {
eventMap := make(map[string]*DomainEvent, 0)
_ = walk(e.meta, nil, func(entity, parent IEntity, children map[string][]IEntity) (err error) {
for _, evt := range entity.GetEvents() {
eventMap[evt.ID] = evt
}
return
})
// 收集已删除的实体发送的事件
for _, del := range e.meta.GetDeleted() {
_ = walk(del, nil, func(entity, parent IEntity, children map[string][]IEntity) (err error) {
for _, evt := range entity.GetEvents() {
eventMap[evt.ID] = evt
}
return
})
}
events := make([]*DomainEvent, 0)
for _, evt := range eventMap {
events = append(events, evt)
}
// 事件根据发送时间 + id 的顺序排序,id 由 xid 保证单节点严格自增
sort.SliceStable(events, func(i, j int) bool {
return events[i].CreatedAt.Before(events[j].CreatedAt) ||
(events[i].CreatedAt.Equal(events[j].CreatedAt) && events[i].ID < events[j].ID)
})
return events
}
func (e *Stage) makeEventPersistAction(events []*DomainEvent) (*Action, error) {
pos := make([]IModel, len(events))
for i, evt := range events {
po, err := e.options.EventPersist(evt)
if err != nil {
return nil, err
}
pos[i] = po
}
return &Action{
Op: OpInsert,
Models: pos,
PrevModels: []IModel{},
}, nil
}
func (e *Stage) dispatchEvents(ctx context.Context, events []*DomainEvent) (err error) {
if !e.options.WithTransaction {
e.logger.Info("engine not support transaction")
return e.eventBus.Dispatch(ctx, events...)
}
normalEvents, txEvents := make([]*DomainEvent, 0), make([]*DomainEvent, 0)
for _, evt := range events {
if evt.SendType == SendTypeTransaction {
txEvents = append(txEvents, evt)
} else {
normalEvents = append(normalEvents, evt)
}
}
if txEventBus, ok := e.eventBus.(ITransactionEventBus); ok {
if len(txEvents) > 0 {
e.eventCtx, err = txEventBus.DispatchBegin(ctx, txEvents...)
if err != nil {
return err
}
}
if len(normalEvents) > 0 {
if err = txEventBus.Dispatch(ctx, normalEvents...); err != nil {
return err
}
}
return
} else {
// 如果 eventbus 不支持事务,所有事件默认按照普通方式发送
return e.eventBus.Dispatch(ctx, events...)
}
}
func (e *Stage) commit(ctx context.Context) error {
if err := e.persist(ctx); err != nil {
return err
}
if err := e.makeSnapshot(); err != nil {
return err
}
e.unDirty()
return nil
}
func (e *Stage) persist(ctx context.Context) error {
// 发现实体变更
changed, err := e.getEntityChanged()
if err != nil {
return err
}
// 执行保存前的 hook
for _, c := range changed {
for _, entity := range c.children {
if err := execHook(ctx, entity, c.changeType, true); err != nil {
return err
}
}
}
if err := e.putNewID(changed); err != nil {
return err
}
// 转换为持久化 Action 序列
actions, err := e.makeActions(changed)
if err != nil {
return err
}
if err := e.exec(ctx, actions); err != nil {
return err
}
// 执行保存后的 hook
for _, c := range changed {
for _, entity := range c.children {
if err := execHook(ctx, entity, c.changeType, false); err != nil {
return err
}
}
}
// 回收被删除的子实体,被删除的子实体仍可能有事件需要发送
e.recycle(changed)
return nil
}
func execHook(ctx context.Context, entity IEntity, ct changeType, isBefore bool) error {
if ct == newChildren && isBefore {
if saver, ok := entity.(IBeforeCreate); ok {
if err := saver.BeforeCreate(ctx); err != nil {
return err
}
}
} else if ct == newChildren && !isBefore {
if saver, ok := entity.(IAfterCreate); ok {
if err := saver.AfterCreate(ctx); err != nil {
return err
}
}
} else if ct == dirtyChildren && isBefore {
if saver, ok := entity.(IBeforeUpdate); ok {
if err := saver.BeforeUpdate(ctx); err != nil {
return err
}
}
} else if ct == dirtyChildren && !isBefore {
if saver, ok := entity.(IAfterUpdate); ok {
if err := saver.AfterUpdate(ctx); err != nil {
return err
}
}
} else if ct == deleteChildren && isBefore {
if saver, ok := entity.(IBeforeDelete); ok {
if err := saver.BeforeDelete(ctx); err != nil {
return err
}
}
} else if ct == deleteChildren && !isBefore {
if saver, ok := entity.(IAfterDelete); ok {
if err := saver.AfterDelete(ctx); err != nil {
return err
}
}
}
return nil
}
func (e *Stage) exec(ctx context.Context, actions []*Action) error {
for _, a := range actions {
if err := e.executor.Exec(ctx, a); err != nil {
return err
}
}
e.result.Actions = append(e.result.Actions, actions...)
return nil
}
func (e *Stage) setOutput(data interface{}) {
e.result.Output = data
}
func (e *Stage) do(ctx context.Context) *Result {
// 创建聚合
var err error
var buildRoots []IEntity
if e.build != nil {
buildRoots, err = e.build(ctx, DomainBuilder{stage: e})
if err != nil {
return ResultErrOrBreak(err)
}
for _, r := range buildRoots {
if r.GetID() == "" {
return ResultErrors(fmt.Errorf("build entities must have ID, for create case, just use container.Add(**) at act func"))
}
}
e.meta.SetChildren(buildRoots)
}
// 保存父子实体关系链
if err = e.makeSnapshot(); err != nil {
return ResultError(err)
}
if e.act != nil {
container := RootContainer{stage: e}
if err := e.act(ctx, container, buildRoots...); err != nil {
return ResultErrOrBreak(err)
} else if len(container.errs) > 0 {
return ResultErrors(container.errs...)
}
}
err = e.persist(ctx)
if err != nil {
return ResultErrors(err)
}
events := e.collectEvents()
if len(events) > 0 && e.options.EventPersist != nil {
action, err := e.makeEventPersistAction(events)
if err != nil {
return ResultErrors(err)
}
if err := e.exec(ctx, []*Action{action}); err != nil {
return ResultError(err)
}
}
// 发送领域事件
if len(events) > 0 {
if e.eventBus == nil {
return ResultErrors(ErrNoEventBusFound)
}
if err := e.dispatchEvents(ctx, events); err != nil {
return ResultErrors(err)
}
}
return e.result
}
type doSave func(ctx context.Context) *Result
func (e *Stage) runOnLock(f doSave, lockKeys ...string) doSave {
return func(ctx context.Context) *Result {
sort.Strings(lockKeys)
for i := 1; i < len(lockKeys); i++ {
if lockKeys[i] == lockKeys[i-1] {
return ResultErrors(fmt.Errorf("lockKey(%s) repeated", lockKeys[i]))
}
}
var lockErr error
ls := make([]interface{}, 0)
for _, id := range lockKeys {
l, err := e.locker.Lock(ctx, fmt.Sprintf("ddd_engine_%s", id))
if err != nil {
lockErr = fmt.Errorf("acquiring redis locker failed: %v", err)
break
}
ls = append(ls, l)
}
defer func() {
for _, l := range ls {
if err := e.locker.UnLock(ctx, l); err != nil {
e.logger.Error(err, "unlock failed")
}
}
}()
if lockErr != nil {
return ResultErrors(lockErr)
}
return f(ctx)
}
}
func (e *Stage) runWithTransaction(f doSave) doSave {
return func(ctx context.Context) *Result {