1.Zeebe是什么?
Camunda公司研發的工作流引擎Zeebe,目標是對微服務的編排。具體詳細介紹可以參考官網:https://zeebe.io/what-is-zeebe/
2.背景
隨着微服務的發展,大家都單體服務進行了拆分,解耦,這樣做引發了另外的一個問題:之前一個接口實現的功能,現在需要調用幾個接口才能完成。如何解決這些原子性的接口呢?
這時候我們想到了Zeebe服務。
3.服務部署
3.1 第一步:安裝環境,不管你是Linux系統還是Win系統,首先需要安裝上docker,因為我的機器是Win系統,本文就是介紹Windows系統下安裝使用情況
確保機器已經安裝docker(沒有安裝的可以下載docker-win,進行安裝)

3.2 第二步:在cmd里面執行命令:
docker run --name zeebe -p 26500:26500 camunda/zeebe:latest
至此,Zeebe服務已經安裝成功了。
4.demo
4.1 第一步:創建一個控制台項目,這個應該都會
4.2 第二步:在項目中引用Zeebe客戶端的nuget包,目前版本是0.11.0

4.3 第三步:建模,使用Zeebe Modeler工具進行建模
我需要實現的流程是:

具體的BPMN代碼如下:
<?xml version="1.0" encoding="UTF-8"?> <bpmn:definitions xmlns:bpmn="http://www.omg.org/spec/BPMN/20100524/MODEL" xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI" xmlns:dc="http://www.omg.org/spec/DD/20100524/DC" xmlns:zeebe="http://camunda.org/schema/zeebe/1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:di="http://www.omg.org/spec/DD/20100524/DI" id="Definitions_1011qyd" targetNamespace="http://bpmn.io/schema/bpmn" exporter="Zeebe Modeler" exporterVersion="0.6.2"> <bpmn:process id="instock-process" name="instock-process" isExecutable="true"> <bpmn:startEvent id="start" name="start"> <bpmn:outgoing>SequenceFlow_instock</bpmn:outgoing> </bpmn:startEvent> <bpmn:serviceTask id="createinstock" name="createinstock"> <bpmn:extensionElements> <zeebe:taskDefinition type="createinstock" retries="3" /> <zeebe:ioMapping> <zeebe:input source="InStockData" target="InStockData" /> </zeebe:ioMapping> </bpmn:extensionElements> <bpmn:incoming>SequenceFlow_instock</bpmn:incoming> <bpmn:outgoing>SequenceFlow_modifystock</bpmn:outgoing> </bpmn:serviceTask> <bpmn:sequenceFlow id="SequenceFlow_instock" name="SequenceFlow_instock" sourceRef="start" targetRef="createinstock" /> <bpmn:serviceTask id="modifystock" name="modifystock"> <bpmn:extensionElements> <zeebe:taskDefinition type="modifystock" retries="3" /> <zeebe:ioMapping> <zeebe:input source="StockData" target="StockData" /> </zeebe:ioMapping> </bpmn:extensionElements> <bpmn:incoming>SequenceFlow_modifystock</bpmn:incoming> <bpmn:outgoing>SequenceFlow_gateway</bpmn:outgoing> </bpmn:serviceTask> <bpmn:sequenceFlow id="SequenceFlow_modifystock" name="SequenceFlow_modifystock" sourceRef="createinstock" targetRef="modifystock" /> <bpmn:exclusiveGateway id="checknum" name="checknum"> <bpmn:incoming>SequenceFlow_gateway</bpmn:incoming> <bpmn:outgoing>morethan300</bpmn:outgoing> <bpmn:outgoing>lessthan300</bpmn:outgoing> </bpmn:exclusiveGateway> <bpmn:sequenceFlow id="SequenceFlow_gateway" name="SequenceFlow_gateway" sourceRef="modifystock" targetRef="checknum" /> <bpmn:serviceTask id="notify" name="notify"> <bpmn:extensionElements> <zeebe:taskDefinition type="notify" retries="3" /> </bpmn:extensionElements> <bpmn:incoming>morethan300</bpmn:incoming> <bpmn:outgoing>SequenceFlow_end</bpmn:outgoing> </bpmn:serviceTask> <bpmn:sequenceFlow id="morethan300" name=">=300" sourceRef="checknum" targetRef="notify"> <bpmn:conditionExpression xsi:type="bpmn:tFormalExpression">stocknum>=300</bpmn:conditionExpression> </bpmn:sequenceFlow> <bpmn:endEvent id="end" name="end"> <bpmn:incoming>lessthan300</bpmn:incoming> <bpmn:incoming>SequenceFlow_end</bpmn:incoming> </bpmn:endEvent> <bpmn:sequenceFlow id="lessthan300" name="lessthan300" sourceRef="checknum" targetRef="end"> <bpmn:conditionExpression xsi:type="bpmn:tFormalExpression">stocknum<300</bpmn:conditionExpression> </bpmn:sequenceFlow> <bpmn:sequenceFlow id="SequenceFlow_end" name="SequenceFlow_end" sourceRef="notify" targetRef="end" /> </bpmn:process> <bpmndi:BPMNDiagram id="BPMNDiagram_1"> <bpmndi:BPMNPlane id="BPMNPlane_1" bpmnElement="instock-process"> <bpmndi:BPMNShape id="_BPMNShape_StartEvent_2" bpmnElement="start"> <dc:Bounds x="112" y="159" width="36" height="36" /> <bpmndi:BPMNLabel> <dc:Bounds x="119" y="202" width="23" height="14" /> </bpmndi:BPMNLabel> </bpmndi:BPMNShape> <bpmndi:BPMNShape id="ServiceTask_0zssdcw_di" bpmnElement="createinstock"> <dc:Bounds x="265" y="137" width="100" height="80" /> </bpmndi:BPMNShape> <bpmndi:BPMNEdge id="SequenceFlow_0yllvib_di" bpmnElement="SequenceFlow_instock"> <di:waypoint x="148" y="177" /> <di:waypoint x="265" y="177" /> <bpmndi:BPMNLabel> <dc:Bounds x="163" y="159" width="88" height="27" /> </bpmndi:BPMNLabel> </bpmndi:BPMNEdge> <bpmndi:BPMNShape id="ServiceTask_1db0jmn_di" bpmnElement="modifystock"> <dc:Bounds x="481" y="137" width="100" height="80" /> </bpmndi:BPMNShape> <bpmndi:BPMNEdge id="SequenceFlow_1uaplin_di" bpmnElement="SequenceFlow_modifystock"> <di:waypoint x="365" y="177" /> <di:waypoint x="481" y="177" /> <bpmndi:BPMNLabel> <dc:Bounds x="383" y="159" width="80" height="27" /> </bpmndi:BPMNLabel> </bpmndi:BPMNEdge> <bpmndi:BPMNShape id="ExclusiveGateway_1sjnk3d_di" bpmnElement="checknum" isMarkerVisible="true"> <dc:Bounds x="723" y="152" width="50" height="50" /> <bpmndi:BPMNLabel> <dc:Bounds x="722" y="128" width="51" height="14" /> </bpmndi:BPMNLabel> </bpmndi:BPMNShape> <bpmndi:BPMNEdge id="SequenceFlow_1hhfiqd_di" bpmnElement="SequenceFlow_gateway"> <di:waypoint x="581" y="177" /> <di:waypoint x="723" y="177" /> <bpmndi:BPMNLabel> <dc:Bounds x="610" y="159" width="85" height="27" /> </bpmndi:BPMNLabel> </bpmndi:BPMNEdge> <bpmndi:BPMNShape id="ServiceTask_016w4wa_di" bpmnElement="notify"> <dc:Bounds x="954" y="319" width="100" height="80" /> </bpmndi:BPMNShape> <bpmndi:BPMNEdge id="SequenceFlow_1ffqddr_di" bpmnElement="morethan300"> <di:waypoint x="748" y="202" /> <di:waypoint x="748" y="359" /> <di:waypoint x="954" y="359" /> <bpmndi:BPMNLabel> <dc:Bounds x="839" y="341" width="32" height="14" /> </bpmndi:BPMNLabel> </bpmndi:BPMNEdge> <bpmndi:BPMNShape id="EndEvent_01b3gni_di" bpmnElement="end"> <dc:Bounds x="1208" y="159" width="36" height="36" /> <bpmndi:BPMNLabel> <dc:Bounds x="1217" y="202" width="19" height="14" /> </bpmndi:BPMNLabel> </bpmndi:BPMNShape> <bpmndi:BPMNEdge id="SequenceFlow_00imkpl_di" bpmnElement="lessthan300"> <di:waypoint x="773" y="177" /> <di:waypoint x="1208" y="177" /> <bpmndi:BPMNLabel> <dc:Bounds x="961" y="159" width="60" height="14" /> </bpmndi:BPMNLabel> </bpmndi:BPMNEdge> <bpmndi:BPMNEdge id="SequenceFlow_0c9jvp6_di" bpmnElement="SequenceFlow_end"> <di:waypoint x="1004" y="319" /> <di:waypoint x="1004" y="177" /> <di:waypoint x="1208" y="177" /> <bpmndi:BPMNLabel> <dc:Bounds x="977" y="245" width="85" height="27" /> </bpmndi:BPMNLabel> </bpmndi:BPMNEdge> </bpmndi:BPMNPlane> </bpmndi:BPMNDiagram> </bpmn:definitions>
4.4 第四步:寫代碼
(1)客戶端代碼:
internal class Program { private static readonly string DemoProcessPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Resources", "instock-process.bpmn"); private static readonly string ZeebeUrl = "127.0.0.1:26500"; private static dynamic WorkflowInstanceVariables = new { stocknum = 100 }; public static async Task Main(string[] args) { InitClient.Initialize(); // create zeebe client var client = ZeebeClient.NewZeebeClient(ZeebeUrl); // deploy // var deployResponse = await client.NewDeployCommand().AddResourceFile(DemoProcessPath).Send(); // create workflow instance // var workflowKey = deployResponse.Workflows[0].WorkflowKey;//2251799813685495 // 模擬調用 var workflowInstance = await client .NewCreateWorkflowInstanceCommand() .WorkflowKey(2251799813685495) .Variables(JsonConvert.SerializeObject(WorkflowInstanceVariables)) .Send(); } }
(2)服務端代碼:
internal class Program { private static Dictionary<string, string> JobTypeAndMethod = new Dictionary<string, string>() { { "createinstock","InStockJobHandler"}, { "modifystock","StockJobHandler"}, { "notify","NotifyJobHandler"} }; private static readonly string ZeebeUrl = "127.0.0.1:26500"; public static async Task Main(string[] args) { InitClient.Initialize(); // create zeebe client var client = ZeebeClient.NewZeebeClient(ZeebeUrl); // open job worker await OpenJobWorkers(client); } private static Task OpenJobWorkers(IZeebeClient client) { using (var signal = new EventWaitHandle(false, EventResetMode.AutoReset)) { foreach (var item in JobTypeAndMethod) { client.NewWorker() .JobType(item.Key) .Handler(JobHandlerFactory.GetJobType(item.Value)) .MaxJobsActive(5) .Name(item.Key) .AutoCompletion() .PollInterval(TimeSpan.FromSeconds(1)) .Timeout(TimeSpan.FromSeconds(10)) .Open(); } // blocks main thread, so that worker can run signal.WaitOne(); } return Task.CompletedTask; } }
客戶端的代碼中,只有第一次會將BPMN文件進行部署,Zeebe服務會返回一個Key,之后如果建模數據不發生改變的情況下,就可以直接使用key進行調用即可了,如果發生變化需要再一次部署才行;
每次部署都會改變工作流程的Version值(默認獲取的事latestVersion)。
至此,一個簡單的Zeebe Demo實現了。
