<a id="datadiode-source-connector-config"></a>

# Configuration Reference for Data Diode Source Connector for Confluent Platform

To use this connector, specify the name of the connector class in the `connector.class` configuration property.

```properties
connector.class=io.confluent.connect.diode.source.DataDiodeSourceConnector
```

Connector-specific configuration properties are described below.

## Diode

`diode.encryption.password`
: The password used to derive a shared secret between the sink and source connectors. You must use the same password in sink and source connectors.
  <br/>
  * Type: password
  * Valid Values: non-empty string of a specific min length
  * Importance: high

`diode.bind.address`
: The hostname or IP address to bind to. By default, this will bind to all interfaces.
  <br/>
  * Type: string
  * Default: 0.0.0.0
  * Importance: medium

`diode.encryption.salt`
: The salt used to derive a shared secret between the sink and source connectors. You must use the same salt in sink and source connectors.
  <br/>
  * Type: password
  * Valid Values: non-empty string of a specific min length
  * Importance: high

`diode.port`
: The UDP port to listen to.
  <br/>
  * Type: int
  * Default: 3456
  * Valid Values: [1024,…,65535]
  * Importance: medium

`diode.encryption.class`
: Fully qualified class used for encryption and decryption of datagram packets. Currently, there are two implementations. `io.confluent.connect.diode.serde.Aes256CbcEncryptor` uses the AES algorithm with a 256 bit symmetric key derived from a password and salt. `io.confluent.connect.diode.serde.NoopEncryptor` disables encryption and decryption and sends packets in plaintext. Custom encryption/decryption algorithms are possible by implementing `io.confluent.connect.diode.serde.Encryptor`.
  <br/>
  * Type: class
  * Default: io.confluent.connect.diode.serde.Aes256CbcEncryptor
  * Importance: medium

`diode.compression.class`
: Fully qualified class used for compression and decompression on datagram packets. Compression is CPU intensive, but reduces size of packets. Enable compression if the records are largely text data. Compression is only effective if multiple records are batched. Currently, there are two implementations. `io.confluent.connect.diode.serde.GzipCompressor` for gzip and `io.confluent.connect.diode.serde.NoopCompressor` to disable compression. You can provide a different implementation by implementing `io.confluent.connect.diode.serde.Compressor`.
  <br/>
  * Type: class
  * Default: io.confluent.connect.diode.serde.NoopCompressor
  * Importance: medium

## Kafka

`missing.records.topic`
: The Kafka topic in which the missing records are written. Also provide the Connect Worker configurations such as `bootstrap.servers` and `client.id` with `missing.records.` as prefix.
  <br/>
  * Type: string
  * Default: “”
  * Importance: medium

`kafka.topic.prefix`
: The prefix to attach to topic names. When the sink connector writes records at the source, it encodes the topic name in the payload. This source connector will try to write to the same topic. Sometimes, it is desirable to prepend a prefix to the topic name.
  <br/>
  * Type: string
  * Default: “”
  * Importance: low

## Auto topic creation

For more information about Auto topic creation, see [Configuring Auto Topic Creation for Source Connectors](/kafka-connectors/self-managed/userguide.html#connect-source-auto-topic-creation).

Configuration properties accept regular expressions (regex) that are defined as
[Java regex](https://docs.oracle.com/javase/8/docs/api/java/util/regex/Pattern.html).

`topic.creation.groups`
: A list of group aliases that are used to define per-group topic configurations for matching topics. A `default` group always exists and matches all topics.
  <br/>
  * Type: List of String types
  * Default: empty
  * Possible Values: The values of this property refer to any additional groups. A `default` group is always defined for topic configurations.

`topic.creation.$alias.replication.factor`
: The replication factor for new topics created by the connector. This value must not be larger than the number of brokers in the Kafka cluster. If this value is larger than the number of Kafka brokers, an error occurs when the connector attempts to create a topic. This is a **required property** for the `default` group. This property is optional for any other group defined in `topic.creation.groups`. Other groups use the Kafka broker default value.
  <br/>
  * Type: int
  * Default: n/a
  * Possible Values: `>= 1` for a specific valid value or `-1` to use the Kafka broker’s default value.

`topic.creation.$alias.partitions`
: The number of topic partitions created by this connector. This is a **required property** for the `default` group. This property is optional for any other group defined in `topic.creation.groups`. Other groups use the Kafka broker default value.
  <br/>
  * Type: int
  * Default: n/a
  * Possible Values: `>= 1` for a specific valid value or `-1` to use the Kafka broker’s default value.

`topic.creation.$alias.include`
: A list of strings that represent regular expressions that match topic names. This list is used to include topics with matching values, and apply this group’s specific configuration to the matching topics. `$alias` applies to any group defined in `topic.creation.groups`. This property does not apply to the `default` group.
  <br/>
  * Type: List of String types
  * Default: empty
  * Possible Values: Comma-separated list of exact topic names or regular expressions.

`topic.creation.$alias.exclude`
: A list of strings representing regular expressions that match topic names. This list is used to exclude topics with matching values from getting the group’s specfic configuration. `$alias` applies to any group defined in `topic.creation.groups`. This property does not apply to the `default` group. Note that exclusion rules override any inclusion rules for topics.
  <br/>
  * Type: List of String types
  * Default: empty
  * Possible Values: Comma-separated list of exact topic names or regular expressions.

`topic.creation.$alias.${kafkaTopicSpecificConfigName}`
: Any of the [Changing Broker Configurations Dynamically](/platform/current/kafka/dynamic-config.html#changing-broker-configurations-dynamically) for the version of the Kafka broker where the records will be written. The broker’s topic-level configuration value is used if the configuration is not specified for the rule. `$alias` applies to the `default` group as well as any group defined in `topic.creation.groups`.
  <br/>
  * Type: property values
  * Default: Kafka broker value

<a id="datadiode-source-connector-license-config"></a>

## Confluent Platform license

`confluent.topic.bootstrap.servers`
A list of host/port pairs to use for establishing the initial connection to the Kafka cluster used for licensing. All servers in the cluster will be discovered from the initial connection. This list should be in the form `host1:port1,host2:port2,...`. Since these servers are just used for the initial connection to discover the full cluster membership (which may change dynamically), this list need not contain the full set of servers (you may want more than one, though, in case a server is down).

* Type: list
* Importance: high

`confluent.topic`
Name of the Kafka topic used for Confluent Platform configuration, including licensing information.

* Type: string
* Default: \_confluent-command
* Importance: low

`confluent.topic.replication.factor`
The replication factor for the Kafka topic used for Confluent Platform configuration, including licensing information. This is used only if the topic does not already exist, and the default of 3 is appropriate for production use. If you are using a development environment with less than 3 brokers, you must set this to the number of brokers (often 1).

* Type: int
* Default: 3
* Importance: low

<!-- WARNING: THIS IS A SHARED FILE AND THE SOURCE IS LOCATED IN DOCS-COMMON. DO NOT ADD TO ANY OTHER REPO. -->

## CSFLE and CSPE configurations

`csfle.enabled`

Accepts a boolean value. CSFLE is enabled for the connector if `csfle.enabled` is set to True.

* Type: boolean
* Default: False

`auto.register.schemas`

Specifies if the Serializer should attempt to register the Schema with Schema Registry.

* Type: boolean
* Default: true
* Importance: medium

`use.latest.version`

Only applies when `auto.register.schemas` is set to false. If `auto.register.schemas` is set to false and `use.latest.version` is set to true, then instead of deriving a schema for the object passed to the client for serialization, Schema Registry uses the latest version of the schema in the subject for serialization.

* Type: boolean
* Default: true
* Importance: medium

### Confluent license properties

You can put license-related properties in the connector configuration, or in license-related properties in the
[Connect worker configuration](https://docs.confluent.io/kafka-connectors/self-managed/license.html#centralized-license-in-the-kconnect-long-worker) instead of in each connector configuration.

This connector is proprietary and requires a license. The license information is stored in the `_confluent-command`
topic. If the broker requires SSL for connections, you must include the security-related `confluent.topic.*` properties
as described below.

`confluent.license`
: Confluent issues enterprise license keys to each subscriber. The license key is text that you can copy and
  paste as the value for `confluent.license`. A trial license allows using the connector for a 30-day trial period. A developer license allows using the connector indefinitely for single-broker development environments.
  <br/>
  If you are a subscriber, contact Confluent Support for more information.
  <br/>
  * Type: string
  * Default: “”
  * Valid Values: Confluent Platform license
  * Importance: high

`confluent.topic.ssl.truststore.location`
: The location of the trust store file.
  <br/>
  * Type: string
  * Default: null
  * Importance: high

`confluent.topic.ssl.truststore.password`
: The password for the trust store file. If a password is not set access to the truststore is still available, but
  integrity checking is disabled.
  <br/>
  * Type: password
  * Default: null
  * Importance: high

`confluent.topic.ssl.keystore.location`
: The location of the key store file. This is optional for client and can be used for two-way authentication for client.
  <br/>
  * Type: string
  * Default: null
  * Importance: high

`confluent.topic.ssl.keystore.password`
: The store password for the key store file. This is optional for client and only needed if ssl.keystore.location is configured.
  <br/>
  * Type: password
  * Default: null
  * Importance: high

`confluent.topic.ssl.key.password`
: The password of the private key in the key store file. This is optional for client.
  <br/>
  * Type: password
  * Default: null
  * Importance: high

`confluent.topic.security.protocol`
: Protocol used to communicate with brokers. Valid values are: PLAINTEXT, SSL, SASL_PLAINTEXT, SASL_SSL.
  <br/>
  * Type: string
  * Default: “PLAINTEXT”
  * Importance: medium

<a id="datadiode-source-license-topic-configuration"></a>

### License topic configuration

A Confluent enterprise license is stored in the `_confluent-command` topic.
This topic is created by default and contains the license that corresponds to
the license key supplied through the `confluent.license` property. No public
keys are stored in Kafka topics.

The following describes how the default `_confluent-command` topic is
generated under different scenarios:

* A 30-day trial license is automatically generated for the `_confluent-command` topic if you do not add the `confluent.license` property or leave this property empty (for example, `confluent.license=`).
* Adding a valid license key (for example, `confluent.license=<valid-license-key>`) adds a valid license in the `_confluent-command` topic.

Here is an example of the minimal properties for development and testing.

You can change the name of the `_confluent-command` topic using the
`confluent.topic` property (for instance, if your environment has strict
naming conventions). The example below shows this change and the configured
Kafka bootstrap server.

```none
confluent.topic=foo_confluent-command
confluent.topic.bootstrap.servers=localhost:9092
```

The example above shows the minimally required bootstrap server property that
you can use for development and testing. For a production environment, you add
the normal producer, consumer, and topic configuration properties to the
connector properties, prefixed with `confluent.topic.`.

### License topic ACLs

The `_confluent-command` topic contains the license that corresponds to the
license key supplied through the `confluent.license` property. It is created
by default. Connectors that access this topic require the following ACLs
configured:

* CREATE and DESCRIBE on the resource cluster, if the connector needs to create the topic.
* DESCRIBE, READ, and WRITE on the `_confluent-command` topic.

  #### IMPORTANT
  You can also use DESCRIBE and READ without WRITE to restrict access to
  read-only for license topic ACLs. If a topic exists, the LicenseManager
  will not try to create the topic.

You can provide access either individually for each principal that will
use the license or use a [wildcard entry](/platform/current/kafka/authorization.html#acl-wildcard-principals) to
allow all clients. The following examples show commands that you can use to
configure ACLs for the resource cluster and `_confluent-command` topic.

1. Set a CREATE and DESCRIBE ACL on the resource cluster:
   ```none
   kafka-acls --bootstrap-server localhost:9092 --command-config adminclient-configs.conf \
   --add --allow-principal User:<principal> \
   --operation CREATE --operation DESCRIBE --cluster
   ```
2. Set a DESCRIBE, READ, and WRITE ACL on the `_confluent-command` topic:
   ```none
   kafka-acls --bootstrap-server localhost:9092 --command-config adminclient-configs.conf \
   --add --allow-principal User:<principal> \
   --operation DESCRIBE --operation READ --operation WRITE --topic _confluent-command
   ```

### Override Default Configuration Properties

You can override the replication factor using
`confluent.topic.replication.factor`. For example, when using a Kafka cluster
as a destination with less than three brokers (for development and testing) you
should set the `confluent.topic.replication.factor` property to `1`.

You can override producer-specific properties by using the
`producer.override.*` prefix (for source connectors) and consumer-specific
properties by using the `consumer.override.*` prefix (for sink connectors).

You can use the defaults or customize the other properties as well. For example,
the `confluent.topic.client.id` property defaults to the name of the connector
with `-licensing` suffix. You can specify the configuration settings for
brokers that require SSL or SASL for client connections using this prefix.

You cannot override the cleanup policy of a topic because the topic always has a
single partition and is compacted. Also, do not specify serializers and
deserializers using this prefix; they are ignored if added.
