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docs/docs/06-operations/10-docker-compose/05-confluent-cloud.md

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+# Using Confluent Cloud
+
+LittleHorse requires [Apache Kafka](https://kafka.apache.org) as its only hard dependency. Kafka is the source-of-truth for the state of a LittleHorse Cluster as all data is stored in Kafka Streams state stores (therefore, the durability of the Changelog Topics determines the durability of the LittleHorse Cluster's data).
+
+Managing Kafka in production is difficult; so users of our open-source community may wish to use a hosted SaaS version of Kafka. The leading Kafka Cloud Service is provided by [Confluent](https://confluent.io), a company founded by the creators of Apache Kafka.
+
+This example shows you how to connect your LittleHorse cluster to Confluent Cloud.
+
+## Docker Compose File
+
+Confluent Cloud uses the `SASL_SSL` protocol with the `PLAIN` Sasl mechanism. before running this example, you must:
+
+1. Create a Confluent Cloud cluster and an API key. You can do so on [Confluent's Cloud Console](https://confluent.cloud/).
+2. Download the API Key file. It should look like the following:
+
+```
+=== Confluent Cloud API key: lkc-0595zp ===
+
+API key:
+XXXXXXXXXXXXXXXX
+
+API secret:
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+
+Bootstrap server:
+pkc-n98pk.us-west-2.aws.confluent.cloud:9092
+```
+
+LittleHorse will expect the `LHS_SASL_JAAS_CONFIG_FILE` environment variable, which points to a flat file on the LH Server's file system whose contents are the required `sasl.jaas.config`. Your `sasl.jaas.config` should look like:
+
+```
+org.apache.kafka.common.security.plain.PlainLoginModule required username='<API key>' password='<API secret>';
+```
+
+Let's do the following:
+
+```
+API_KEY=<your api key from cflt cloud console>
+API_SECRET=<your api secret from cflt cloud console>
+
+# This is for demo purposes. In production please do something more secure.
+mkdir /tmp/cflt-creds
+echo "org.apache.kafka.common.security.plain.PlainLoginModule required username='$API_KEY' password='$API_SECRET';" > /tmp/cflt-creds/sasl-jaas-config.txt
+```
+
+Replace the `<API key>` and `<API secret>` with the values you downloaded from Confluent Cloud, and then run the above script.
+
+Save the following docker-compose file and run: `docker compose up -d`.
+
+:::caution
+Remember to substitute your bootstrap servers!
+:::
+
+```yaml
+services:
+  littlehorse:
+    container_name: lh-server
+    image: ghcr.io/littlehorse-enterprises/littlehorse/lh-server:0.10.1
+    volumes:
+      # Mount a volume to give the LH Server container access to your Confluent creds.
+      - /tmp/cflt-creds:/secrets
+    environment:
+      # NOTE: Please replace your bootstrap servers
+      LHS_KAFKA_BOOTSTRAP_SERVERS: <your-bootstrap-servers-from-confluent>
+
+      # That this comes from where you mount the volume a few lines above
+      LHS_KAFKA_SASL_JAAS_CONFIG_FILE: /secrets/sasl-jaas-config.txt
+      LHS_KAFKA_SASL_MECHANISM: PLAIN
+      LHS_KAFKA_SECURITY_PROTOCOL: SASL_SSL
+      LHS_SHOULD_CREATE_TOPICS: "true"
+      LHS_HEALTH_SERVICE_PORT: "1822"
+
+      LHS_REPLICATION_FACTOR: "3"
+    restart: on-failure
+    healthcheck:
+      test: curl -f localhost:1822/liveness
+      interval: 5s
+    ports:
+      - "2023:2023"
+  dashboard:
+    container_name: lh-dashboard
+    image: ghcr.io/littlehorse-enterprises/littlehorse/lh-dashboard:0.10.1
+    environment:
+      LHC_API_HOST: littlehorse
+      LHC_API_PORT: 2023
+      LHC_OAUTH_ENABLED: false
+    restart: on-failure
+    ports:
+      - "8080:3000"
+```
+
+## Configuring the Clients
+
+Once you have created the LH Cluster using Docker Compose, the next step is to access it. For example, you can use one of our [quickstarts](../../05-developer-guide/00-install.md#get-started) with the following configurations.
+
+The dashboard can be accessed at [`http://localhost:8080`](http://localhost:8080).
+
+### CLI Configs
+
+The `lhctl` CLI is configured using (by default) the `${HOME}/.config/littlehorse.config` file.
+
+```
+LHC_API_HOST=localhost
+LHC_API_PORT=2023
+```
+
+:::tip
+You can override the location of your configuration file for `lhctl` by using the `--configFile` option.
+:::
+
+### Worker Configs
+
+Workers are configured when you create an `LHConfig` object according to [our documentation](../../05-developer-guide/02-client-configuration.md#creating-the-lhconfig). You need to pass in certain properties (either directly to the `LHConfig` constructor, through a `Properties` file, or through environment variables).
+
+For this example, your workers should be configured as follows:
+
+```
+LHC_API_HOST=localhost
+LHC_API_PORT=2023
+LHW_SERVER_CONNECT_LISTENER=PLAIN
+```
+
+:::tip
+If you walk through our [quickstarts](../../05-developer-guide/00-install.md#get-started), the code in all three assumes that your configuration is set as environment variables.
+:::