
### Download the script to install nvm

```
curl -sL https://raw.githubusercontent.com/nvm-sh/nvm/v0.35.0/install.sh -o install_nvm.sh
```

### Run the script

```
bash install_nvm.sh
```

### Restart terminal

### Verify nvm

```
nvm list
```

### Install Nodo.js 14

```
nvm install v14
```


Install nvm for Running Different Node.js Version Locally


### Login

You can try Kafka for 30 days as free, so just login into Kafka with your email.
At GTM, click Triggers > Custom Events, and enter the event name as `contact_lead`.
![Get start with Kafka](/images/kafka-how-to-get-started/img1.png)

#### create a cluster

Once register with new email, you'll receive $400 credit as free trial for 30 days.

### Get start with event driven application with C#

#### Set up a topic

Here, we enter the topic name manually at UI, we'll need to setup cluster key and secret later in order to communicate from c# client.
![create a kafka topic online](/images/kafka-how-to-get-started/img2.png)

Click the **_Create Kafka cluster API key_** to get API key.

#### Produce Data

Follow is C# version of code to send message to kafka as string key and value

```C#
    static void SendKafkaString(string topic, string key, string value)
    {
        IConfiguration configuration = readConfig();
        Message<string, string> message = new Message<string, string> { Key = key, Value = value };
        using (var producer = new ProducerBuilder<string, string>(configuration.AsEnumerable()).Build())
        {
            producer.Produce(topic, message,
              (deliveryReport) =>
              {
                  KafkaResult(deliveryReport, topic);
              }
            );

            producer.Flush(TimeSpan.FromSeconds(10));
        }
    }
```

```C#
SendKafkaString("topic_0", "key_2000", "test12");
```

This is the actual result shows at Kafka UI.
![kafka message result](/images/kafka-how-to-get-started/img3.png)

```C#
var myJson = @"{
    ""str"": ""a string"",
    ""int"": 1,
    ""obj"": {
    ""key"": ""value""
    }
}";

SendKafkaString("topic_0", "key_2000", myJson);
```

Since the value type is string, we can also sending as JSON to Kafka.
![kafka message result](/images/kafka-how-to-get-started/img4.png)

Following is how to use serialize object as JSON to Kafka with C# client.

```C#
var objectTest = new ModelClass { Name = "yo" };
SendKafkaBytes("topic_0", "key_2100", System.Text.Json.JsonSerializer.SerializeToUtf8Bytes(objectTest));
```

This's the content of the code, which take byte array as parameter.

```C#
static void SendKafkaBytes(string topic, string key, byte[] value)
{
    IConfiguration configuration = readConfig();
    Message<string, byte[]> message = new() { Key = key, Value = value };
    using var producer = new ProducerBuilder<string, byte[]>(configuration.AsEnumerable()).Build();
    producer.Produce(topic, message,
        (deliveryReport) =>
        {
            KafkaResult(deliveryReport, topic);
        }
    );

    producer.Flush(TimeSpan.FromSeconds(10));
}
```

This's the result, how to send object to Kafka.
![kafka message result](/images/kafka-how-to-get-started/img5.png)

#### Consume Data


Category nvm

Install nvm for Running Different Node.js Version Locally

Install nvm for Running Different Node.js Version Locally