# Kafka Client Quick Start for Confluent Cloud You can write Kafka client applications to connect to Confluent Cloud in any supported language. You just need to configure the clients using the Confluent Cloud cluster credentials. Official Confluent clients are available for: - [Java](https://docs.confluent.io/clients-kafka-java/current/overview.html) - [librdkafka](https://github.com/edenhill/librdkafka) and derived clients, including [Golang](https://github.com/confluentinc/confluent-kafka-go), [.NET](https://github.com/confluentinc/confluent-kafka-dotnet), and [Python](https://github.com/confluentinc/confluent-kafka-python) This document covers how to properly configure a client. If you have already configured a client and are looking for examples on writing a client application, see the “Hello, World!” [code examples](/platform/current/tutorials/examples/clients/docs/clients-all-examples.html) that produce to and consume from any Kafka cluster, including Confluent Cloud clusters. ## Security requirements All clients must support TLS 1.2 encryption and either SASL_PLAIN or SASL_OAUTHBEARER authentication. For detailed security configuration, certificate management, and TLS requirements, see [Client Configuration Properties](client-configs.md#client-producer-consumer-config-recs-cc). ## Configure clients Clients must be configured properly to connect to a Confluent Cloud cluster. For a subset of client languages, you can also configure clients to connect to a Confluent Cloud Schema Registry cluster. You can obtain a configuration file prefilled with necessary credentials either from the Confluent Cloud Console or on the Confluent CLI. ### Configure clients from the Confluent Cloud Console The easiest way to get started connecting your client apps to Confluent Cloud is to copy and paste the configuration file from the Confluent Cloud Console. 1. Log in to Confluent Cloud. 2. Select an environment. 3. Select a cluster. 4. Select **Clients** from the navigation menu. 5. (Optional) Click **+ New client** button. 6. Select the language you are using for your client application. ![image](images/cloud-client-languages.png) 7. After you have selected a language, create or use existing API keys for your Kafka cluster and Schema Registry cluster as needed. Then, copy and paste the displayed configuration into your client application source code. ![image](images/cloud-client-configuration-example.png) ### Configure clients from the Confluent CLI For [Confluent CLI](https://docs.confluent.io/confluent-cli/current/overview.html) frequent users, once you have set up context in the CLI, you can use one-line command [confluent kafka client-config create](https://docs.confluent.io/confluent-cli/current/command-reference/kafka/client-config/index.html#confluent-kafka-client-config) to create a configuration file for connecting your client apps to Confluent Cloud. The following table lists client languages, corresponding language ID, and whether the language supports Confluent Cloud Schema Registry configuration. For languages that support Confluent Cloud Schema Registry configuration, you can optionally configure it for your client apps by passing Schema Registry information via the flags to the command. | Language | Language ID | Support for Confluent Cloud Schema Registry | Notes | |-------------|---------------|-----------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------| | Clojure | `clojure` | No | | | C/C++ | `cpp` | No | See examples: [C/C++ examples (librdkafka)](https://github.com/edenhill/librdkafka/tree/master/examples) | | C# | `csharp` | No | | | Go | `go` | Yes | See examples: [confluent-kafka-go/examples](https://github.com/confluentinc/confluent-kafka-go/tree/master/examples) | | Groovy | `groovy` | No | | | Java | `java` | Yes | | | Kotlin | `kotlin` | No | | | Ktor | `ktor` | Yes | | | JavaScript | `javascript` | Yes | See examples: [confluent-kafka-javascript/examples](https://github.com/confluentinc/confluent-kafka-javascript/tree/master/examples) | | Python | `python` | Yes | See examples: [confluent-kafka-python/examples](https://github.com/confluentinc/confluent-kafka-python/tree/master/examples) | | REST API | `restapi` | Yes | | | Ruby | `ruby` | No | | | Rust | `rust` | No | | | Scala | `scala` | No | | | Spring Boot | `springboot` | Yes | | Prerequisites: : - [Access to Confluent Cloud](https://www.confluent.io/confluent-cloud/) with an active cluster. - [Install the Confluent CLI](https://docs.confluent.io/confluent-cli/current/install.html). 1. Log in to your cluster using the [confluent login](https://docs.confluent.io/confluent-cli/current/command-reference/confluent_login.html) command with the cluster URL specified. ```none confluent login ``` ```none Enter your Confluent Cloud credentials: Email: susan@myemail.com Password: ``` 2. Set the Confluent Cloud [environment](../security/access-control/hierarchy/cloud-environments.md#cloud-environments). 1. Get the environment ID. ```none confluent environment list ``` Your output should resemble: ```none Id | Name +--------------+--------------------+ * t2703 | default env-abc123 | demo-env-102893 env-xyz123 | ccloud-demo env-wxy123 | data-lineage-demo env-abc12d | my-new-environment ``` 2. Set the environment using the ID (``). ```none confluent environment use ``` Your output should resemble: ```none Now using "env-xyz123" as the default (active) environment. ``` 3. Set the cluster to use. 1. Get the cluster ID. ```none confluent kafka cluster list ``` Your output should resemble: ```none Id | Name | Type | Cloud | Region | Availability | Status +-------------+-----------+-------+----------+----------+--------------+--------+ lkc-oymmj | cluster_1 | BASIC | gcp | us-east4 | single-zone | UP * lkc-7k6kj | cluster_0 | BASIC | gcp | us-east1 | single-zone | UP ``` 2. Set the cluster using the ID (``). This is the cluster where the commands are run. ```none confluent kafka cluster use ``` To verify the selected cluster after setting it, type `confluent kafka cluster list` again. The selected cluster will have an asterisk (`*`) next to it. 4. Create an API key and secret, and save them. You can generate the API key on the Confluent CLI or from the Confluent Cloud Console. Be sure to save the API key and secret. You can use either a Kafka cluster API key scoped to the specific cluster or a [global API key](../security/authenticate/workload-identities/service-accounts/api-keys/overview.md#cloud-global-api-keys). A global API key works identically to a Kafka cluster key for client authentication. Use the same `sasl.username` and `sasl.password` configuration fields. Global API keys are useful when your application connects to multiple clusters or also accesses other Confluent Cloud resources such as Schema Registry or Flink. #### NOTE Global API keys do not support [Basic](../clusters/cluster-types.md#basic-cluster) and [Standard](../clusters/cluster-types.md#standard-cluster) Kafka clusters. For those cluster types, use a resource-scoped Kafka cluster API key. ### Confluent CLI 1. Run the following command to create the API key and secret, using the ID (``). ```bash confluent api-key create --resource ``` Your output should resemble: ```none It may take a couple of minutes for the API key to be ready. Save the API key and secret. The secret is not retrievable later. +---------+------------------------------------------------------------------+ | API Key | ABC123xyz | | Secret | 123xyzABC123xyzABC123xyzABC123xyzABC123xyzABC123xyzABC123xyzABCx | +---------+------------------------------------------------------------------+ ``` For more information, see [Use API Keys to Authenticate to Confluent Cloud](../security/authenticate/workload-identities/service-accounts/api-keys/overview.md#cloud-api-key-resource). ### Confluent Cloud Console 1. In the console, click the **Kafka API keys** tab and click **Create key**. Save the key and secret, then click the checkbox next to **I have saved my API key and secret and am ready to continue.** ![image](images/cloud-api-key-confirm.png) 2. Add the API secret with `confluent api-key store `. When you create an API key with the CLI, it is automatically stored locally. However, when you create an API key using the console, API, or with the CLI on another machine, the secret is not available for CLI use until you store it. This is required because secrets cannot be retrieved after creation. ```bash confluent api-key store --resource ``` For more information, see [Use API Keys to Authenticate to Confluent Cloud](../security/authenticate/workload-identities/service-accounts/api-keys/overview.md#cloud-api-key-resource). 5. Set the API key to use for Confluent CLI commands, using the ID (``). ```none confluent api-key use --resource ``` 6. Create a client configuration file for the language of your choice, using language ID (``). Then, copy and paste the displayed configuration into your client application source code. See [Client Language Table](#client-language-table) for a list of language IDs and whether the language supports Schema Registry configuration. - For the output of command `confluent kafka client-config create `, the client configuration file is printed to **stdout** and the errors or warnings are printed to **stderr**. You can redirect the command output to separate files by doing the following: ```bash confluent kafka client-config create 1> config-file.config 2> errors-warnings-file.err ``` - If you do not want to use the CLI context, you can alternatively pass all the necessary information via flags: ```bash confluent kafka client-config create \ --environment \ --cluster \ --api-key --api-secret \ --schema-registry-api-key --schema-registry-api-secret # only for languages that support Schema Registry configuration ``` - For languages that do NOT support Schema Registry configuration, run the following command: ```bash confluent kafka client-config create ``` - For languages that support Schema Registry configuration, run the following command: ```bash confluent kafka client-config create \ --schema-registry-api-key \ --schema-registry-api-secret ``` ### Related content * For tips and recommendations for configuring resilient clients, see [Client Configuration Settings for Confluent Cloud](client-configs.md#client-producer-consumer-config-recs-cc). * For more information about using the CLI, see [confluent kafka client-config create](https://docs.confluent.io/confluent-cli/current/command-reference/kafka/client-config/index.html#confluent-kafka-client-config).