手撸golang GO与微服务 Saga模式之8 集成测试
缘起
最近阅读<<Go微服务实战>> (刘金亮, 2021.1)
本系列笔记拟采用golang练习之
Saga模式
- saga模式将分布式长事务切分为一系列独立短事务
- 每个短事务是可通过补偿动作进行撤销的
- 事务动作和补动作偿都是幂等的, 允许重复执行而不会有副作用
Saga由一系列的子事务“Ti”组成，
每个Ti都有对应的补偿“Ci”，
当Ti出现问题时Ci用于处理Ti执行带来的问题。
可以通过下面的两个公式理解Saga模式。
T = T1 T2 … Tn
T = TCT
Saga模式的核心理念是避免使用长期持有锁（如14.2.2节介绍的两阶段提交）的长事务，
而应该将事务切分为一组按序依次提交的短事务，
Saga模式满足ACD（原子性、一致性、持久性）特征。
摘自 <<Go微服务实战>> 刘金亮, 2021.1
目标
- 为实现saga模式的分布式事务, 先撸一个pub/sub事务消息队列服务
- 事务消息队列服务的功能性要求
- 消息不会丢失: 消息的持久化
- 消息的唯一性: 要求每个消息有全局ID和子事务ID
- 确保投递成功: 投递队列持久化, 投递状态持久化, 失败重试
子目标(Day 8)
- 创建虚拟的库存服务
- 启动时, 注册到MQ
- 接收到订单创建的消息时, 扣减库存
- 扣库成功时, 经MQ通知订单服务扣库成功
- 扣库失败时, 经MQ通知订单服务扣库失败
设计
- IStockService: 模拟的库存服务接口
- tStockService: 虚拟库存服务, 实现IStockService接口
- NotifySaleOrderCreated: 用于监听订单创建消息的http回调处理器
单元测试
order_test.go
- 初始化10个产品库存
- 订单服务, 创建订单1, 尝试扣减1个库存, 预期成功
- 订单服务, 创建订单2, 尝试扣减10个库存, 预期失败
- 校验订单1的最终状态为出库成功
- 校验订单2的最终状态为出库失败
package saga
import (
"github.com/jmoiron/sqlx"
"learning/gooop/saga/mqs/cmd"
"learning/gooop/saga/mqs/database"
"learning/gooop/saga/mqs/logger"
"learning/gooop/saga/order"
"learning/gooop/saga/stock"
"sync"
"testing"
"time"
)
var gRunOnce sync.Once
func fnBootMQS() {
gRunOnce.Do(func() {
// boot mqs
go cmd.BootMQS()
// wait for mqs up
time.Sleep(1 * time.Second)
})
}
func fnAssertTrue (t *testing.T, b bool, msg string) {
if !b {
t.Fatal(msg)
}
}
func Test_SagaSaleOrder(t *testing.T) {
// prepare mqs
fnClearDB(t)
fnBootMQS()
// 1 create prod stock
prodID := "test-prod-1"
err := stock.MockStockService.AddStock(prodID, 10)
if err != nil {
t.Fatal(err)
}
// create order 1
o1 := &order.SaleOrder{
OrderID: "test-order-1",
ProductID: prodID,
CustomerID: "test-customer-1",
Quantity: 1,
Price: 100,
Amount: 100,
CreateTime: time.Now().UnixNano(),
StatusFlag: order.StatusNotDelivered,
}
err = order.MockSaleOrderService.Create(o1)
if err != nil {
t.Fatal(err)
}
// create order 2
time.Sleep(10*time.Millisecond)
o2 := &order.SaleOrder{
OrderID: "test-order-2",
ProductID: prodID,
CustomerID: "test-customer-2",
Quantity: 10,
Price: 100,
Amount: 1000,
CreateTime: time.Now().UnixNano(),
StatusFlag: order.StatusNotDelivered,
}
err = order.MockSaleOrderService.Create(o2)
if err != nil {
t.Fatal(err)
}
time.Sleep(1 * time.Second)
logger.Logf("============================================")
log := "tSaleOrderService.beginSubscribeMQ, done"
fnAssertTrue(t, logger.Count(log)==1, "expecting log: " + log)
log = "tSaleOrderService.publishMQ, done, order=test-order-1"
fnAssertTrue(t, logger.Count(log)==1, "expecting log: " + log)
log = "tSaleOrderService.publishMQ, done, order=test-order-2"
fnAssertTrue(t, logger.Count(log)==1, "expecting log: " + log)
log = "stock.NotifySaleOrderCreated, order=test-order-1"
fnAssertTrue(t, logger.Count(log)==1, "expecting log: " + log)
log = "stock.NotifySaleOrderCreated, order=test-order-2"
fnAssertTrue(t, logger.Count(log)==1, "expecting log: " + log)
o1 = order.MockSaleOrderService.Get(o1.OrderID)
fnAssertTrue(t, o1.StatusFlag == order.StatusStockOutboundDone, "expecting o1 done")
o2 = order.MockSaleOrderService.Get(o2.OrderID)
fnAssertTrue(t, o2.StatusFlag == order.StatusStockOutboundFailed, "expecting o2 failed")
logger.Logf("test passed")
}
func fnClearDB(t *testing.T) {
fnDBExec(t, "delete from subscriber")
fnDBExec(t, "delete from tx_msg")
fnDBExec(t, "delete from delivery_queue")
fnDBExec(t, "delete from success_queue")
}
func fnDBExec(t *testing.T, sql string, args... interface{}) int {
rows := []int64{ 0 }
err := database.DB(func(db *sqlx.DB) error {
r,e := db.Exec(sql, args...)
if e != nil {
return e
}
rows[0], e = r.RowsAffected()
if e != nil {
return e
}
return nil
})
if err != nil {
t.Fatal(err)
}
return int(rows[0])
}
测试输出
$ go test -v order_test.go
=== RUN Test_SagaSaleOrder
23:55:54.292132442 eventbus.Pub, event=system.boot, handler=gDeliveryService.handleBootEvent
[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.
[GIN-debug] [WARNING] Running in "debug" mode. Switch to "release" mode in production.
- using env: export GIN_MODE=release
- using code: gin.SetMode(gin.ReleaseMode)
[GIN-debug] GET /ping --> learning/gooop/saga/mqs/handlers.Ping (4 handlers)
[GIN-debug] POST /subscribe --> learning/gooop/saga/mqs/handlers.Subscribe (4 handlers)
[GIN-debug] POST /publish --> learning/gooop/saga/mqs/handlers.Publish (4 handlers)
[GIN-debug] POST /notify --> learning/gooop/saga/mqs/handlers.Notify (4 handlers)
[GIN-debug] POST /notify/sale-order.stock.outbound --> learning/gooop/saga/order.NotifyStockOutbound (4 handlers)
[GIN-debug] POST /notify/sale-order.created --> learning/gooop/saga/stock.NotifySaleOrderCreated (4 handlers)
[GIN-debug] Listening and serving HTTP on :3333
23:55:54.292287032 tDeliveryService.beginCleanExpiredWorkers
23:55:54.292345845 tDeliveryService.beginCreatingWorkers
23:55:54.356542981 handlers.Subscribe, msg=&{sale-order-service sale-order.stock.outbound http://localhost:3333/notify/sale-order.stock.outbound 1616086554355593476}
23:55:54.356524325 handlers.Subscribe, msg=&{stock-service sale-order.created http://localhost:3333/notify/sale-order.created 1616086554355598830}
23:55:54.365256441 handlers.Subscribe, event=subscriber.registered, msg=&{sale-order-service sale-order.stock.outbound http://localhost:3333/notify/sale-order.stock.outbound 1616086554355593476}
23:55:54.365271105 eventbus.Pub, event=subscriber.registered, handler=gDeliveryService.handleSubscriberRegistered
[GIN] 2021/03/18 - 23:55:54 | 200 | 8.865173ms | ::1 | POST "/subscribe"
[GIN] 2021/03/18 - 23:55:54 | 200 | 8.882138ms | ::1 | POST "/subscribe"
23:55:54.365488163 tSaleOrderService.beginSubscribeMQ, done
23:55:54.365861542 database.DB, err=empty rows
23:55:54.366239244 tDeliveryWorker.afterInitialLoad, clientID=sale-order-service, rows=0
23:55:54.373588493 handlers.Subscribe, event=subscriber.registered, msg=&{stock-service sale-order.created http://localhost:3333/notify/sale-order.created 1616086554355598830}
23:55:54.373605972 eventbus.Pub, event=subscriber.registered, handler=gDeliveryService.handleSubscriberRegistered
[GIN] 2021/03/18 - 23:55:54 | 200 | 17.189632ms | ::1 | POST "/subscribe"
[GIN] 2021/03/18 - 23:55:54 | 200 | 17.205549ms | ::1 | POST "/subscribe"
23:55:54.373843032 tStockService.beginSubscribeMQ, done
23:55:54.3743926 database.DB, err=empty rows
23:55:54.374499757 tDeliveryWorker.afterInitialLoad, clientID=stock-service, rows=0
23:55:55.292336699 tStockService.AddStock, done, prodId=test-prod-1, stock=0, delta=0, after=10
23:55:55.323746568 handlers.Publish, msg=test-order-1/test-order-1/sale-order.created, msgId=112
[GIN] 2021/03/18 - 23:55:55 | 200 | 31.112478ms | ::1 | POST "/publish"
[GIN] 2021/03/18 - 23:55:55 | 200 | 31.125855ms | ::1 | POST "/publish"
23:55:55.323811205 handlers.Publish, pubLiveMsg 112
23:55:55.323910377 tSaleOrderService.publishMQ, done, order=test-order-1/&{test-order-1 test-customer-1 test-prod-1 1 100 100 1616082955292352151 0}
23:55:55.324227736 handlers.Publish, pubLiveMsg, msgId=112, rows=1
23:55:55.324273573 handlers.Publish, event=msg.published, clientID=stock-service, msg=test-order-1/test-order-1/http://localhost:3333/notify/sale-order.created
23:55:55.32428051 eventbus.Pub, event=msg.published, handler=tLiveMsgSource.sale-order-service
23:55:55.324285512 eventbus.Pub, event=msg.published, handler=tLiveMsgSource.stock-service
23:55:55.324292286 tLiveMsgSource.handleMsgPublished, clientID=stock-service, msg=test-order-1/test-order-1/sale-order.created
23:55:55.324346678 tDeliveryWorker.beginPollAndDeliver, msg from live=&{98 stock-service http://localhost:3333/notify/sale-order.created 112 test-order-1 test-order-1 sale-order-service 1616082955292352151 sale-order.created {"OrderID":"test-order-1","CustomerID":"test-customer-1","ProductID":"test-prod-1","Quantity":1,"Price":100,"Amount":100,"CreateTime":1616082955292352151,"StatusFlag":0} 0 0}
23:55:55.33925766 handlers.Publish, msg=test-order-2/test-order-2/sale-order.created, msgId=113
[GIN] 2021/03/18 - 23:55:55 | 200 | 15.264561ms | ::1 | POST "/publish"
[GIN] 2021/03/18 - 23:55:55 | 200 | 15.280884ms | ::1 | POST "/publish"
23:55:55.339353768 handlers.Publish, pubLiveMsg 113
23:55:55.339446893 tSaleOrderService.publishMQ, done, order=test-order-2/&{test-order-2 test-customer-2 test-prod-1 10 100 1000 1616082955302734821 0}
23:55:55.339909493 handlers.Publish, pubLiveMsg, msgId=113, rows=1
23:55:55.339919874 handlers.Publish, event=msg.published, clientID=stock-service, msg=test-order-2/test-order-2/http://localhost:3333/notify/sale-order.created
23:55:55.339925049 eventbus.Pub, event=msg.published, handler=tLiveMsgSource.sale-order-service
23:55:55.339929964 eventbus.Pub, event=msg.published, handler=tLiveMsgSource.stock-service
23:55:55.339935935 tLiveMsgSource.handleMsgPublished, clientID=stock-service, msg=test-order-2/test-order-2/sale-order.created
23:55:55.350117186 tDeliveryWorker.deliver, begin, id=stock-service, msg=test-order-1/test-order-1
23:55:55.35041833 stock.NotifySaleOrderCreated, order=test-order-1/&{test-order-1 test-customer-1 test-prod-1 1 100 100 1616082955292352151 0}
23:55:55.350429178 tStockService.AddStock, done, prodId=test-prod-1, stock=10, delta=-1, after=9
[GIN] 2021/03/18 - 23:55:55 | 200 | 88.872µs | ::1 | POST "/notify/sale-order.created"
[GIN] 2021/03/18 - 23:55:55 | 200 | 133.617µs | ::1 | POST "/notify/sale-order.created"
23:55:55.350592351 tDeliveryWorker.deliver, OK, id=stock-service, msg=test-order-1/test-order-1
23:55:55.367336707 tDeliveryWorker.afterDeliverySuccess, done, id=stock-service, msg=test-order-1/test-order-1
23:55:55.36738322 tDeliveryWorker.beginPollAndDeliver, msg from live=&{99 stock-service http://localhost:3333/notify/sale-order.created 113 test-order-2 test-order-2 sale-order-service 1616082955302734821 sale-order.created {"OrderID":"test-order-2","CustomerID":"test-customer-2","ProductID":"test-prod-1","Quantity":10,"Price":100,"Amount":1000,"CreateTime":1616082955302734821,"StatusFlag":0} 0 0}
23:55:55.367530495 database.DB, err=empty rows
23:55:55.374978535 tDeliveryWorker.deliver, begin, id=stock-service, msg=test-order-2/test-order-2
23:55:55.375201115 stock.NotifySaleOrderCreated, order=test-order-2/&{test-order-2 test-customer-2 test-prod-1 10 100 1000 1616082955302734821 0}
23:55:55.375211216 tStockService.AddStock, failed, prodId=test-prod-1, stock=9, delta=-10
23:55:55.375219558 tStockService.HandleSaleOrderCreated, err=insufficient stock, order=&{test-order-2 test-customer-2 test-prod-1 10 100 1000 1616082955302734821 0}
[GIN] 2021/03/18 - 23:55:55 | 200 | 102.52µs | ::1 | POST "/notify/sale-order.created"
[GIN] 2021/03/18 - 23:55:55 | 200 | 116.933µs | ::1 | POST "/notify/sale-order.created"
23:55:55.375354895 tDeliveryWorker.deliver, OK, id=stock-service, msg=test-order-2/test-order-2
23:55:55.389901711 tDeliveryWorker.afterDeliverySuccess, done, id=stock-service, msg=test-order-2/test-order-2
23:55:55.38993077 tDeliveryWorker.beginPollAndDeliver, msg from db=&{99 stock-service http://localhost:3333/notify/sale-order.created 113 test-order-2 test-order-2 sale-order-service 1616082955302734821 sale-order.created {"OrderID":"test-order-2","CustomerID":"test-customer-2","ProductID":"test-prod-1","Quantity":10,"Price":100,"Amount":1000,"CreateTime":1616082955302734821,"StatusFlag":0} 1 1616082955367401386}
23:55:55.420121681 handlers.Publish, msg=test-order-1/test-order-1.outbound/sale-order.stock.outbound, msgId=114
[GIN] 2021/03/18 - 23:55:55 | 200 | 69.507171ms | ::1 | POST "/publish"
[GIN] 2021/03/18 - 23:55:55 | 200 | 69.520805ms | ::1 | POST "/publish"
23:55:55.420220719 handlers.Publish, pubLiveMsg 114
23:55:55.420321792 tStockService.publishMQ, done, msg=&{test-order-1 test-order-1.outbound stock-service 1616082955350432496 sale-order.stock.outbound 1}
23:55:55.42071623 handlers.Publish, pubLiveMsg, msgId=114, rows=1
23:55:55.420731889 handlers.Publish, event=msg.published, clientID=sale-order-service, msg=test-order-1/test-order-1.outbound/http://localhost:3333/notify/sale-order.stock.outbound
23:55:55.420741935 eventbus.Pub, event=msg.published, handler=tLiveMsgSource.sale-order-service
23:55:55.420746401 eventbus.Pub, event=msg.published, handler=tLiveMsgSource.stock-service
23:55:55.420755367 tLiveMsgSource.handleMsgPublished, clientID=sale-order-service, msg=test-order-1/test-order-1.outbound/sale-order.stock.outbound
23:55:55.42079505 tDeliveryWorker.beginPollAndDeliver, msg from live=&{100 sale-order-service http://localhost:3333/notify/sale-order.stock.outbound 114 test-order-1 test-order-1.outbound stock-service 1616082955350432496 sale-order.stock.outbound 1 0 0}
23:55:55.435844021 handlers.Publish, msg=test-order-2/test-order-2.outbound/sale-order.stock.outbound, msgId=115
[GIN] 2021/03/18 - 23:55:55 | 200 | 15.407267ms | ::1 | POST "/publish"
[GIN] 2021/03/18 - 23:55:55 | 200 | 15.420327ms | ::1 | POST "/publish"
23:55:55.4359058 handlers.Publish, pubLiveMsg 115
23:55:55.436026025 tStockService.publishMQ, done, msg=&{test-order-2 test-order-2.outbound stock-service 1616082955375214295 sale-order.stock.outbound 0}
23:55:55.436398324 handlers.Publish, pubLiveMsg, msgId=115, rows=1
23:55:55.436409937 handlers.Publish, event=msg.published, clientID=sale-order-service, msg=test-order-2/test-order-2.outbound/http://localhost:3333/notify/sale-order.stock.outbound
23:55:55.43642793 eventbus.Pub, event=msg.published, handler=tLiveMsgSource.sale-order-service
23:55:55.436433697 eventbus.Pub, event=msg.published, handler=tLiveMsgSource.stock-service
23:55:55.43644379 tLiveMsgSource.handleMsgPublished, clientID=sale-order-service, msg=test-order-2/test-order-2.outbound/sale-order.stock.outbound
23:55:55.446599314 tDeliveryWorker.deliver, begin, id=sale-order-service, msg=test-order-1/test-order-1.outbound
23:55:55.446809726 order.NotifyStockOutbound, orderID=test-order-1, succeeded=true
[GIN] 2021/03/18 - 23:55:55 | 200 | 61.898µs | ::1 | POST "/notify/sale-order.stock.outbound"
[GIN] 2021/03/18 - 23:55:55 | 200 | 81.911µs | ::1 | POST "/notify/sale-order.stock.outbound"
23:55:55.446951354 tDeliveryWorker.deliver, OK, id=sale-order-service, msg=test-order-1/test-order-1.outbound
23:55:55.462584405 tDeliveryWorker.afterDeliverySuccess, done, id=sale-order-service, msg=test-order-1/test-order-1.outbound
23:55:55.462615131 tDeliveryWorker.beginPollAndDeliver, msg from live=&{101 sale-order-service http://localhost:3333/notify/sale-order.stock.outbound 115 test-order-2 test-order-2.outbound stock-service 1616082955375214295 sale-order.stock.outbound 0 0 0}
23:55:55.469999185 tDeliveryWorker.deliver, begin, id=sale-order-service, msg=test-order-2/test-order-2.outbound
23:55:55.470163043 order.NotifyStockOutbound, orderID=test-order-2, succeeded=false
[GIN] 2021/03/18 - 23:55:55 | 200 | 85.14µs | ::1 | POST "/notify/sale-order.stock.outbound"
[GIN] 2021/03/18 - 23:55:55 | 200 | 105.638µs | ::1 | POST "/notify/sale-order.stock.outbound"
23:55:55.470369408 tDeliveryWorker.deliver, OK, id=sale-order-service, msg=test-order-2/test-order-2.outbound
23:55:55.486229145 tDeliveryWorker.afterDeliverySuccess, done, id=sale-order-service, msg=test-order-2/test-order-2.outbound
23:55:56.302885199 ============================================
23:55:56.303470422 test passed
--- PASS: Test_SagaSaleOrder (2.05s)
PASS
ok command-line-arguments 2.057s
IStockService.go
模拟的库存服务接口
package stock;
import "learning/gooop/saga/order"
type IStockService interface {
GetStock(prodId string) int
AddStock(prodId string, delta int) error
HandleSaleOrderCreated(it *order.SaleOrder) error
}
tStockService.go
虚拟库存服务, 实现IStockService接口
package stock
import (
"bytes"
"encoding/json"
"errors"
"io/ioutil"
"learning/gooop/saga/mqs/logger"
"learning/gooop/saga/mqs/models"
"learning/gooop/saga/order"
"net/http"
"sync"
"time"
)
type tStockService struct {
rwmutex *sync.RWMutex
stock map[string]int
bMQReady bool
publishQueue chan *models.TxMsg
}
func newStockService() IStockService {
it := new(tStockService)
it.init()
return it
}
func (me *tStockService) init() {
me.rwmutex = new(sync.RWMutex)
me.stock = make(map[string]int)
me.bMQReady = false
me.publishQueue = make(chan *models.TxMsg, gMQMaxQueuedMsg)
go func() {
time.Sleep(100*time.Millisecond)
go me.beginSubscribeMQ()
go me.beginPublishMQ()
}()
}
func (me *tStockService) GetStock(prodId string) int {
me.rwmutex.RLock()
defer me.rwmutex.RUnlock()
it,ok := me.stock[prodId]
if ok {
return it
} else {
return 0
}
}
func (me *tStockService) AddStock(prodId string, delta int) error {
me.rwmutex.RLock()
defer me.rwmutex.RUnlock()
it,ok := me.stock[prodId]
if ok {
n := it + delta
if n < 0 {
logger.Logf("tStockService.AddStock, failed, prodId=%s, stock=%d, delta=%d", prodId, it, delta)
return gInsufficientStockError
} else {
logger.Logf("tStockService.AddStock, done, prodId=%s, stock=%d, delta=%d, after=%d", prodId, it, delta, n)
me.stock[prodId] = n
}
} else {
if delta < 0 {
logger.Logf("tStockService.AddStock, failed, prodId=%s, stock=0, delta=%d", prodId, delta)
return gInsufficientStockError
} else {
logger.Logf("tStockService.AddStock, done, prodId=%s, stock=0, delta=%d, after=%d", prodId, it, delta)
me.stock[prodId] = delta
}
}
return nil
}
func (me *tStockService) beginSubscribeMQ() {
expireDuration := int64(1 * time.Hour)
subscribeDuration := 20 * time.Minute
pauseDuration := 3*time.Second
lastSubscribeTime := int64(0)
for {
now := time.Now().UnixNano()
if now - lastSubscribeTime >= int64(subscribeDuration) {
expireTime := now + expireDuration
err := fnSubscribeMQ(expireTime)
if err != nil {
me.bMQReady = false
logger.Logf("tStockService.beginSubscribeMQ, failed, err=%v", err)
} else {
lastSubscribeTime = now
me.bMQReady = true
logger.Logf("tStockService.beginSubscribeMQ, done")
}
}
time.Sleep(pauseDuration)
}
}
func fnSubscribeMQ(expireTime int64) error {
msg := &models.SubscribeMsg{
ClientID: gMQClientID,
Topic: gMQSubscribeTopic,
NotifyUrl: gMQServerURL + PathOfNotifySaleOrderCreated,
ExpireTime: expireTime,
}
url := gMQServerURL + "/subscribe"
return fnPost(msg, url)
}
func fnPost(msg interface{}, url string) error {
body,_ := json.Marshal(msg)
rsp, err := http.Post(url, "application/json;charset=utf-8", bytes.NewReader(body))
if err != nil {
return err
}
defer rsp.Body.Close()
j, err := ioutil.ReadAll(rsp.Body)
if err != nil {
return err
}
ok := &models.OkMsg{}
err = json.Unmarshal(j, ok)
if err != nil {
return err
}
if !ok.OK {
return gMQReplyFalse
}
return nil
}
func (me *tStockService) beginPublishMQ() {
for {
select {
case msg := <- me.publishQueue :
me.publishMQ(msg)
break
}
}
}
func (me *tStockService) publishMQ(msg *models.TxMsg) {
url := gMQServerURL + "/publish"
for i := 0;i < gMQMaxPublishRetry;i++ {
err := fnPost(msg, url)
if err != nil {
logger.Logf("tStockService.publishMQ, failed, err=%v, msg=%v", err, msg)
time.Sleep(gMQPublishInterval)
} else {
logger.Logf("tStockService.publishMQ, done, msg=%v", msg)
return
}
}
// publish failed
logger.Logf("tStockService.publishMQ, failed max retries, msg=%v", msg)
}
func (me *tStockService) HandleSaleOrderCreated(it *order.SaleOrder) error {
msg := &models.TxMsg{}
msg.GlobalID = it.OrderID
msg.SubID = it.OrderID + ".outbound"
msg.SenderID = gMQClientID
msg.Topic = gMQPublishTopic
err := me.AddStock(it.ProductID, -it.Quantity)
msg.CreateTime = time.Now().UnixNano()
if err != nil {
logger.Logf("tStockService.HandleSaleOrderCreated, err=%s, order=%v", err.Error(), it)
msg.Content = "0"
} else {
msg.Content = "1"
}
if len(me.publishQueue) >= gMQMaxQueuedMsg {
logger.Logf("tStockService.HandleSaleOrderCreated, err=%s, order=%v", gMQBlocked.Error(), it)
return gMQBlocked
} else {
me.publishQueue <- msg
return err
}
}
var gInsufficientStockError = errors.New("insufficient stock")
var gMQReplyFalse = errors.New("mq reply false")
var gMQBlocked = errors.New("mq blocked")
var gMQMaxPublishRetry = 10
var gMQPublishInterval = 1*time.Second
var gMQSubscribeTopic = "sale-order.created"
var gMQPublishTopic = "sale-order.stock.outbound"
var gMQClientID = "stock-service"
var gMQServerURL = "http://localhost:3333"
var gMQMaxQueuedMsg = 1024
var MockStockService = newStockService()
NotifySaleOrderCreated.go
用于监听订单创建消息的http回调处理器
package stock
import (
"encoding/json"
"github.com/gin-gonic/gin"
"io/ioutil"
"learning/gooop/saga/mqs/logger"
"learning/gooop/saga/mqs/models"
"learning/gooop/saga/order"
"net/http"
)
func NotifySaleOrderCreated(c *gin.Context) {
body := c.Request.Body
defer body.Close()
j, e := ioutil.ReadAll(body)
if e != nil {
logger.Logf("stock.NotifySaleOrderCreated, failed ioutil.ReadAll")
c.JSON(http.StatusBadRequest, gin.H { "ok": false, "error": e.Error()})
return
}
msg := &models.TxMsg{}
e = json.Unmarshal(j, msg)
if e != nil {
logger.Logf("stock.NotifySaleOrderCreated, failed json.Unmarshal msg")
c.JSON(http.StatusBadRequest, gin.H { "ok": false, "error": e.Error()})
return
}
order := &order.SaleOrder{}
e = json.Unmarshal([]byte(msg.Content), order)
if e != nil {
logger.Logf("stock.NotifySaleOrderCreated, failed json.Unmarshal order")
c.JSON(http.StatusBadRequest, gin.H { "ok": false, "error": e.Error()})
return
}
logger.Logf("stock.NotifySaleOrderCreated, order=%s/%v", order.OrderID, order)
// notify stock service
_ = MockStockService.HandleSaleOrderCreated(order)
c.JSON(http.StatusOK, gin.H{ "ok": true })
}
var PathOfNotifySaleOrderCreated = "/notify/sale-order.created"
(未完待续)
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