四、Function调度

4.1 Router

现在，将KisFlow提供对外Function开放注册能力，首先我们要定义一些注册函数原型，和管理这些Function的Router映射关系类型。

创建kis-flow/kis/router.go，定义原型如下：

kis-flow/kis/router.go

package kis

import "context"

// FaaS Function as a Service
type FaaS func(context.Context, Flow) error

// funcRouter
// key: Function Name
// value: Function 回调自定义业务
type funcRouter map[string]FaaS

// flowRouter
// key: Flow Name
// value: Flow
type flowRouter map[string]Flow

FaaS：是开发者给KisFlow注册的Function回调业务函数原型，需要传递两个参数，Context和Flow，Context主要承载业务的上线文环境，Flow主要承载KisFlow的上下文环境，我们可以通过Flow获取当前Function的配置信息，当前Function的数据信息，已经Flow上其他节点的Function相关信息等。

funcRouter: 管理FunctionName和FaaS业务回调的映射关系Map，是一个私有类型，不对外提供引用。需要注意的是，funcRouter的key是FunctionName，因为FunctionId是生成的随机Id，开发者在注册路由的时候，并无法预判和可读，所以关联的业务回调是与FunctionName做的映射关系。

flowRouter:管理FlowName和Flow实例的映射关系Map，是一个私有类型，不对外提供引用。flowRouter依然是FlowName的映射关系。

4.2 KisPool

KisFlow提供一个用来管理全部全局映射关系的类KisPool，KisPool包含Router，且提供对Router的管理能力。

4.2.1 KisPool的定义

创建 kis-flow/kis/pool.go 文件，来创建kis_pool模块。

kis-flow/kis/pool.go

package kis

import (
    "context"
    "errors"
    "fmt"
    "kis-flow/log"
    "sync"
)

var _poolOnce sync.Once

//  kisPool 用于管理全部的Function和Flow配置的池子
type kisPool struct {
    fnRouter funcRouter   // 全部的Function管理路由
    fnLock   sync.RWMutex // fnRouter 锁

    flowRouter flowRouter   // 全部的flow对象
    flowLock   sync.RWMutex // flowRouter 锁
}

// 单例
var _pool *kisPool

// Pool 单例构造
func Pool() *kisPool {
    _poolOnce.Do(func() {
        //创建kisPool对象
        _pool = new(kisPool)

        // fnRouter初始化
        _pool.fnRouter = make(funcRouter)

        // flowRouter初始化
        _pool.flowRouter = make(flowRouter)
    })

    return _pool
}

kis_pool采用单例模式，Pool()方法为获取当前的单例，有关fnRouter和 flowRouter在生命周期只会初始化一次，通过sync.Once来控制。

4.2.2 注册及获取Flow

KisPool可以提供添加和获取Flow信息的接口，如下：

kis-flow/kis/pool.go

func (pool *kisPool) AddFlow(name string, flow Flow) {
    pool.flowLock.Lock()
    defer pool.flowLock.Unlock()

    if _, ok := pool.flowRouter[name]; !ok {
        pool.flowRouter[name] = flow
    } else {
        errString := fmt.Sprintf("Pool AddFlow Repeat FlowName=%s\n", name)
        panic(errString)
    }

    log.Logger().InfoF("Add FlowRouter FlowName=%s\n", name)
}

func (pool *kisPool) GetFlow(name string) Flow {
    pool.flowLock.RLock()
    defer pool.flowLock.RUnlock()

    if flow, ok := pool.flowRouter[name]; ok {
        return flow
    } else {
        return nil
    }
}

AddFlow会根据相同的FlowName进行做重复校验，相同的Flow无法注册多次。

4.2.3 注册及调度Function

KisPool提供注册Funciton回调和调度Funciton方法， 如下。

kis-flow/kis/pool.go

// FaaS 注册 Function 计算业务逻辑, 通过Function Name 索引及注册
func (pool *kisPool) FaaS(fnName string, f FaaS) {
    pool.fnLock.Lock()
    defer pool.fnLock.Unlock()

    if _, ok := pool.fnRouter[fnName]; !ok {
        pool.fnRouter[fnName] = f
    } else {
        errString := fmt.Sprintf("KisPoll FaaS Repeat FuncName=%s", fnName)
        panic(errString)
    }

    log.Logger().InfoF("Add KisPool FuncName=%s", fnName)
}

// CallFunction 调度 Function
func (pool *kisPool) CallFunction(ctx context.Context, fnName string, flow Flow) error {

    if f, ok := pool.fnRouter[fnName]; ok {
        return f(ctx, flow)
    }

    log.Logger().ErrorFX(ctx, "FuncName: %s Can not find in KisPool, Not Added.\n", fnName)

    return errors.New("FuncName: " + fnName + " Can not find in NsPool, Not Added.")
}

在CallFunction()中，需要传递参数Flow，作为数据流调度的上下文环境。 开发者在自定义FaaS中可以通过Flow来获取一些Funciton信息，所以这里需要给Flow补充几个获取配置信息的接口，之后如果再需要，再继续补充，具体如下：

kis-flow/kis/flow.go

type Flow interface {
    // Run 调度Flow，依次调度Flow中的Function并且执行
    Run(ctx context.Context) error
    // Link 将Flow中的Function按照配置文件中的配置进行连接
    Link(fConf *config.KisFuncConfig, fParams config.FParam) error
    // CommitRow 提交Flow数据到即将执行的Function层
    CommitRow(row interface{}) error
    // Input 得到flow当前执行Function的输入源数据
    Input() common.KisRowArr

    // ++++++++++++++++++++++++++++++++++
    // GetName 得到Flow的名称
    GetName() string
    // GetThisFunction 得到当前正在执行的Function
    GetThisFunction() Function
    // GetThisFuncConf 得到当前正在执行的Function的配置
    GetThisFuncConf() *config.KisFuncConfig
}

kis-flow/flow/kis_flow.go

func (flow *KisFlow) GetName() string {
    return flow.Name
}

func (flow *KisFlow) GetThisFunction() kis.Function {
    return flow.ThisFunction
}

func (flow *KisFlow) GetThisFuncConf() *config.KisFuncConfig {
    return flow.ThisFunction.GetConfig()
}

4.3 KisFunction引用KisPool调度

现在，我们就可以在KisFunctionX中的Call()来通过Pool进行调度了，依次修改每个Function的Call()方法。

kis-flow/function/kis_function_c.go

package function

import (
    "context"
    "kis-flow/kis"
    "kis-flow/log"
)

type KisFunctionC struct {
    BaseFunction
}

func (f *KisFunctionC) Call(ctx context.Context, flow kis.Flow) error {
    log.Logger().InfoF("KisFunctionC, flow = %+v\n", flow)

    // 通过KisPool 路由到具体的执行计算Function中
    if err := kis.Pool().CallFunction(ctx, f.Config.FName, flow); err != nil {
        log.Logger().ErrorFX(ctx, "Function Called Error err = %s\n", err)
        return err
    }

    return nil
}

kis-flow/function/kis_function_e.go

package function

import (
    "context"
    "kis-flow/kis"
    "kis-flow/log"
)

type KisFunctionE struct {
    BaseFunction
}

func (f *KisFunctionE) Call(ctx context.Context, flow kis.Flow) error {
    log.Logger().InfoF("KisFunctionE, flow = %+v\n", flow)

    // 通过KisPool 路由到具体的执行计算Function中
    if err := kis.Pool().CallFunction(ctx, f.Config.FName, flow); err != nil {
        log.Logger().ErrorFX(ctx, "Function Called Error err = %s\n", err)
        return err
    }

    return nil
}

kis-flow/function/kis_function_l.go

package function

import (
    "context"
    "kis-flow/kis"
    "kis-flow/log"
)

type KisFunctionL struct {
    BaseFunction
}

func (f *KisFunctionL) Call(ctx context.Context, flow kis.Flow) error {
    log.Logger().InfoF("KisFunctionL, flow = %+v\n", flow)

    // 通过KisPool 路由到具体的执行计算Function中
    if err := kis.Pool().CallFunction(ctx, f.Config.FName, flow); err != nil {
        log.Logger().ErrorFX(ctx, "Function Called Error err = %s\n", err)
        return err
    }

    return nil
}

kis-flow/function/kis_function_s.go

package function

import (
    "context"
    "kis-flow/kis"
    "kis-flow/log"
)

type KisFunctionS struct {
    BaseFunction
}

func (f *KisFunctionS) Call(ctx context.Context, flow kis.Flow) error {
    log.Logger().InfoF("KisFunctionS, flow = %+v\n", flow)

    // 通过KisPool 路由到具体的执行计算Function中
    if err := kis.Pool().CallFunction(ctx, f.Config.FName, flow); err != nil {
        log.Logger().ErrorFX(ctx, "Function Called Error err = %s\n", err)
        return err
    }

    return nil
}

kis-flow/function/kis_function_v.go

package function

import (
    "context"
    "kis-flow/kis"
    "kis-flow/log"
)

type KisFunctionV struct {
    BaseFunction
}

func (f *KisFunctionV) Call(ctx context.Context, flow kis.Flow) error {
    log.Logger().InfoF("KisFunctionV, flow = %+v\n", flow)

    // 通过KisPool 路由到具体的执行计算Function中
    if err := kis.Pool().CallFunction(ctx, f.Config.FName, flow); err != nil {
        log.Logger().ErrorFX(ctx, "Function Called Error err = %s\n", err)
        return err
    }

    return nil
}

4.4 KisPool单元测试

接下来我们来针对KisPool进行单元测试。

4.4.1 自定义FaaS

kis-flow/test/kis_pool_test.go

package test

import (
    "context"
    "fmt"
    "kis-flow/common"
    "kis-flow/config"
    "kis-flow/flow"
    "kis-flow/kis"
    "testing"
)

func funcName1Handler(ctx context.Context, flow kis.Flow) error {
    fmt.Println("---> Call funcName1Handler ----")

    for index, row := range flow.Input() {
        // 打印数据
        str := fmt.Sprintf("In FuncName = %s, FuncId = %s, row = %s", flow.GetThisFuncConf().FName, flow.GetThisFunction().GetId(), row)
        fmt.Println(str)

        // 计算结果数据
        resultStr := fmt.Sprintf("data from funcName[%s], index = %d", flow.GetThisFuncConf().FName, index)

        // 提交结果数据
        _ = flow.CommitRow(resultStr)
    }

    return nil
}

func funcName2Handler(ctx context.Context, flow kis.Flow) error {

    for _, row := range flow.Input() {
        str := fmt.Sprintf("In FuncName = %s, FuncId = %s, row = %s", flow.GetThisFuncConf().FName, flow.GetThisFunction().GetId(), row)
        fmt.Println(str)
    }

    return nil
}

4.4.2 注册FaaS及启动Flow

kis-flow/test/kis_pool_test.go

func TestNewKisPool(t *testing.T) {

    ctx := context.Background()

    // 0. 注册Function
    kis.Pool().FaaS("funcName1", funcName1Handler)
    kis.Pool().FaaS("funcName2", funcName2Handler)

    // 1. 创建2个KisFunction配置实例
    source1 := config.KisSource{
        Name: "公众号抖音商城户订单数据",
        Must: []string{"order_id", "user_id"},
    }

    source2 := config.KisSource{
        Name: "用户订单错误率",
        Must: []string{"order_id", "user_id"},
    }

    myFuncConfig1 := config.NewFuncConfig("funcName1", common.C, &source1, nil)
    if myFuncConfig1 == nil {
        panic("myFuncConfig1 is nil")
    }

    myFuncConfig2 := config.NewFuncConfig("funcName2", common.E, &source2, nil)
    if myFuncConfig2 == nil {
        panic("myFuncConfig2 is nil")
    }

    // 2. 创建一个 KisFlow 配置实例
    myFlowConfig1 := config.NewFlowConfig("flowName1", common.FlowEnable)

    // 3. 创建一个KisFlow对象
    flow1 := flow.NewKisFlow(myFlowConfig1)

    // 4. 拼接Functioin 到 Flow 上
    if err := flow1.Link(myFuncConfig1, nil); err != nil {
        panic(err)
    }
    if err := flow1.Link(myFuncConfig2, nil); err != nil {
        panic(err)
    }

    // 5. 提交原始数据
    _ = flow1.CommitRow("This is Data1 from Test")
    _ = flow1.CommitRow("This is Data2 from Test")
    _ = flow1.CommitRow("This is Data3 from Test")

    // 6. 执行flow1
    if err := flow1.Run(ctx); err != nil {
        panic(err)
    }
}

cd到kis-flow/test/下执行命令：

go test -test.v -test.paniconexit0 -test.run TestNewKisPool

结果如下：

=== RUN   TestNewKisPool
Add KisPool FuncName=funcName1
Add KisPool FuncName=funcName2
context.Background
====> After CommitSrcData, flow_name = flowName1, flow_id = flow-1fdae2bfac684f1d8edf89d9000208c0
All Level Data =
 map[FunctionIdFirstVirtual:[This is Data1 from Test This is Data2 from Test This is Data3 from Test]]

KisFunctionC, flow = &{Id:flow-1fdae2bfac684f1d8edf89d9000208c0 Name:flowName1 Conf:0xc0000e27c0 Funcs:map[func-51527b72a4ee447fb0bd494bda9a84ad:0xc0000c0190 func-9cd2ab870b384794b312d2be10bb06fa:0xc0000c01e0] FlowHead:0xc0000c0190 FlowTail:0xc0000c01e0 flock:{w:{state:0 sema:0} writerSem:0 readerSem:0 readerCount:0 readerWait:0} ThisFunction:0xc0000c0190 ThisFunctionId:func-51527b72a4ee447fb0bd494bda9a84ad PrevFunctionId:FunctionIdFirstVirtual funcParams:map[func-51527b72a4ee447fb0bd494bda9a84ad:map[] func-9cd2ab870b384794b312d2be10bb06fa:map[]] fplock:{w:{state:0 sema:0} writerSem:0 readerSem:0 readerCount:0 readerWait:0} buffer:[] data:map[FunctionIdFirstVirtual:[This is Data1 from Test This is Data2 from Test This is Data3 from Test]] inPut:[This is Data1 from Test This is Data2 from Test This is Data3 from Test]}

---> Call funcName1Handler ----
In FuncName = funcName1, FuncId = func-51527b72a4ee447fb0bd494bda9a84ad, row = This is Data1 from Test
In FuncName = funcName1, FuncId = func-51527b72a4ee447fb0bd494bda9a84ad, row = This is Data2 from Test
In FuncName = funcName1, FuncId = func-51527b72a4ee447fb0bd494bda9a84ad, row = This is Data3 from Test
context.Background
 ====> After commitCurData, flow_name = flowName1, flow_id = flow-1fdae2bfac684f1d8edf89d9000208c0
All Level Data =
 map[FunctionIdFirstVirtual:[This is Data1 from Test This is Data2 from Test This is Data3 from Test] func-51527b72a4ee447fb0bd494bda9a84ad:[data from funcName[funcName1], index = 0 data from funcName[funcName1], index = 1 data from funcName[funcName1], index = 2]]

KisFunctionE, flow = &{Id:flow-1fdae2bfac684f1d8edf89d9000208c0 Name:flowName1 Conf:0xc0000e27c0 Funcs:map[func-51527b72a4ee447fb0bd494bda9a84ad:0xc0000c0190 func-9cd2ab870b384794b312d2be10bb06fa:0xc0000c01e0] FlowHead:0xc0000c0190 FlowTail:0xc0000c01e0 flock:{w:{state:0 sema:0} writerSem:0 readerSem:0 readerCount:0 readerWait:0} ThisFunction:0xc0000c01e0 ThisFunctionId:func-9cd2ab870b384794b312d2be10bb06fa PrevFunctionId:func-51527b72a4ee447fb0bd494bda9a84ad funcParams:map[func-51527b72a4ee447fb0bd494bda9a84ad:map[] func-9cd2ab870b384794b312d2be10bb06fa:map[]] fplock:{w:{state:0 sema:0} writerSem:0 readerSem:0 readerCount:0 readerWait:0} buffer:[] data:map[FunctionIdFirstVirtual:[This is Data1 from Test This is Data2 from Test This is Data3 from Test] func-51527b72a4ee447fb0bd494bda9a84ad:[data from funcName[funcName1], index = 0 data from funcName[funcName1], index = 1 data from funcName[funcName1], index = 2]] inPut:[data from funcName[funcName1], index = 0 data from funcName[funcName1], index = 1 data from funcName[funcName1], index = 2]}

In FuncName = funcName2, FuncId = func-9cd2ab870b384794b312d2be10bb06fa, row = data from funcName[funcName1], index = 0
In FuncName = funcName2, FuncId = func-9cd2ab870b384794b312d2be10bb06fa, row = data from funcName[funcName1], index = 1
In FuncName = funcName2, FuncId = func-9cd2ab870b384794b312d2be10bb06fa, row = data from funcName[funcName1], index = 2
--- PASS: TestNewKisPool (0.00s)
PASS
ok      kis-flow/test   0.520s

经过日志的详细校验，结果是符合我们预期的。

好了，现在Function的业务能力已经开放给开发者了，接下来我们来继续完善KisFlow的能力。

4.5 【V0.3】源代码

github.com/aceld/kis-flow/releases...

作者:刘丹冰Aceld github: github.com/aceld

KisFlow开源项目地址：github.com/aceld/kis-flow