The Zeebe C# client documentation

The Zeebe C# client to communicate with a Zeebe gateway/cluster.

The client is a C# wrapper implementation around the GRPC generated client. It makes it possible to communicate with Zeebe Gateway via the GRPC protocol, see the Zeebe documentation for more information about the Zeebe project.

The Client is available as a Nuget package.

API documentation

• Zeebe.Client.IZeebeClient
• Zeebe.Client.Api.Commands
• Zeebe.Client.Api.Responses
• Zeebe.Client.Api.Worker

Cloud-Example

//
//    Copyright (c) 2021 camunda services GmbH (info@camunda.com)
//
//    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.
 
using System;
using System.Threading.Tasks;
using NLog.Extensions.Logging;
using Zeebe.Client.Impl.Builder;
 
namespace Client.Cloud.Example
{
    public class Program
    {
        public static async Task Main(string[] args)
        {
            var zeebeClient =
                    CamundaCloudClientBuilder.Builder()
                        .UseClientId("ZEEBE_CLIENT_ID")
                        .UseClientSecret("ZEEBE_CLIENT_SECRET")
                        .UseContactPoint("ZEEBE_ADDRESS")
                    .UseLoggerFactory(new NLogLoggerFactory()) // optional
                    .Build();
 
            var topology = await zeebeClient.TopologyRequest().Send();
 
            Console.WriteLine("Hello: " + topology);
        }
    }
}

Example

//
//    Copyright (c) 2018 camunda services GmbH (info@camunda.com)
//
//    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.
 
using System;
using System.IO;
using System.Threading;
using System.Threading.Tasks;
using NLog.Extensions.Logging;
using Zeebe.Client;
using Zeebe.Client.Api.Responses;
using Zeebe.Client.Api.Worker;
 
namespace Client.Examples
{
    internal class Program
    {
        private static readonly string DemoProcessPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Resources", "demo-process.bpmn");
        private static readonly string ZeebeUrl = "0.0.0.0:26500";
        private static readonly string ProcessInstanceVariables = "{\"a\":\"123\"}";
        private static readonly string JobType = "payment-service";
        private static readonly string WorkerName = Environment.MachineName;
        private static readonly long WorkCount = 100L;
 
        public static async Task Main(string[] args)
        {
            // create zeebe client
            var client = ZeebeClient.Builder()
                .UseLoggerFactory(new NLogLoggerFactory())
                .UseGatewayAddress(ZeebeUrl)
                .UsePlainText()
                .Build();
 
            var topology = await client.TopologyRequest()
                .Send();
            Console.WriteLine(topology);
            await client.NewPublishMessageCommand()
                .MessageName("csharp")
                .CorrelationKey("wow")
                .Variables("{\"realValue\":2}")
                .Send();
 
            // deploy
            var deployResponse = await client.NewDeployCommand()
                .AddResourceFile(DemoProcessPath)
                .Send();
 
            // create process instance
            var processDefinitionKey = deployResponse.Processes[0].ProcessDefinitionKey;
 
            var processInstance = await client
                .NewCreateProcessInstanceCommand()
                .ProcessDefinitionKey(processDefinitionKey)
                .Variables(ProcessInstanceVariables)
                .Send();
 
            await client.NewSetVariablesCommand(processInstance.ProcessInstanceKey).Variables("{\"wow\":\"this\"}").Local().Send();
 
            for (var i = 0; i < WorkCount; i++)
            {
                await client
                    .NewCreateProcessInstanceCommand()
                    .ProcessDefinitionKey(processDefinitionKey)
                    .Variables(ProcessInstanceVariables)
                    .Send();
            }
 
            // open job worker
            using (var signal = new EventWaitHandle(false, EventResetMode.AutoReset))
            {
                client.NewWorker()
                      .JobType(JobType)
                      .Handler(HandleJob)
                      .MaxJobsActive(5)
                      .Name(WorkerName)
                      .AutoCompletion()
                      .PollInterval(TimeSpan.FromSeconds(1))
                      .Timeout(TimeSpan.FromSeconds(10))
                      .Open();
 
                // blocks main thread, so that worker can run
                signal.WaitOne();
            }
        }
 
        private static void HandleJob(IJobClient jobClient, IJob job)
        {
            // business logic
            var jobKey = job.Key;
            Console.WriteLine("Handling job: " + job);
 
            if (jobKey % 3 == 0)
            {
                jobClient.NewCompleteJobCommand(jobKey)
                    .Variables("{\"foo\":2}")
                    .Send()
                    .GetAwaiter()
                    .GetResult();
            }
            else if (jobKey % 2 == 0)
            {
                jobClient.NewFailCommand(jobKey)
                    .Retries(job.Retries - 1)
                    .ErrorMessage("Example fail")
                    .Send()
                    .GetAwaiter()
                    .GetResult();
            }
            else
            {
                // auto completion
            }
        }
    }
}