Configuration Reference for Azure Blob Storage Source Connector for Confluent Platform

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

connector.class=io.confluent.connect.azure.blob.storage.AzureBlobStorageSourceConnector

Connector-specific configuration properties are described below.

Azure Parameters

azblob.account.name

The account name. Must include 3-24 alphanumeric characters.

  • Type: string
  • Valid Values: [3,…,24]
  • Importance: high
azblob.account.key

The Azure Storage account key.

  • Type: password
  • Valid Values: password must be non-blank
  • Importance: high
azblob.container.name

The container name. Must be between 3-63 alphanumeric and ‘-‘ characters.

  • Type: string
  • Valid Values: [3,…,63]
  • Importance: medium
azblob.proxy.password

Azure Proxy Password. Use this property only if you need to access Azure through a proxy. Using azblob.proxy.password instead of embedding the username and password in azblob.proxy.url allows the password to be hidden in the logs.

  • Type: password
  • Default: [hidden]
  • Importance: low
azblob.retry.retries

Specifies the maximum number of retries attempts an operation will be tried before producing an error. A value of 1 means 1 try and 1 retry. The actual number of retry attempts is determined by the Azure client based on multiple factors, like the value of this parameter, the type of exception that occurred, and the throttling settings of the underlying Azure client.

  • Type: int
  • Default: 3
  • Valid Values: [1,…]
  • Importance: medium
azblob.retry.backoff.ms

Specifies the amount of delay to use before retrying an operation in milliseconds. The delay increases exponentially with each retry up to a maximum specified by MaxRetryDelay.

  • Type: long
  • Default: 4000
  • Valid Values: [0,…]
  • Importance: low
azblob.retry.max.backoff.ms

Specifies the maximum delay, in milliseconds, allowed before retrying an operation.

  • Type: long
  • Default: 120000
  • Valid Values: [1,…]
  • Importance: low
azblob.retry.secondary.host

If a secondary Host is specified, retries will be tried against this host. Before you set this field, make sure you understand the issues around reading stale and potentially-inconsistent data. For more information, see Designing highly available applications using read-access geo-redundant storage.

  • Type: string
  • Default: null
  • Valid Values: either URI with one of these schemes: http, https, or should be and empty string
  • Importance: low
azblob.proxy.url

Azure Proxy settings encoded in URL syntax. Use this property only if you need to access Azure through a proxy.

  • Type: string
  • Default: “”
  • Valid Values: either URI with one of these schemes: ‘http’, ‘https’, or should be and empty string
  • Importance: low
azblob.proxy.user

Azure Proxy User. Use this property only if you need to access Azure through a proxy. Using azblob.proxy.user instead of embedding the username and password in azblob.proxy.url allows the password to be hidden in the logs.

  • Type: string
  • Default: null
  • Importance: low
azblob.connection.timeout.ms

Indicates the maximum time allowed for any single try of an HTTP request. When transferring large amounts of data, the default value may not be sufficient. Override this value based on the bandwidth available to the host machine and proximity to the Storage service. A good starting point may be 60 seconds per MB of anticipated-payload-size.

  • Type: long
  • Default: 30000
  • Valid Values: [1,…,2147483647000]
  • Importance: medium
azblob.sas.token

A shared access signature (SAS) is a URI that grants restricted access rights to Azure Storage resources. You must provide a SAS to clients whom you don’t want to entrust with your storage account key and to whom you wish to delegate access to certain storage account resources.

  • Type: password
  • Default: null
  • Importance: high

Azure Parameters (Generalized Connector Only)

mode

The connector’s operation mode.

  • Type: string
  • Default: RESTORE_BACKUP
  • Valid Values: [GENERIC, RESTORE_BACKUP]
  • Importance: high
  • Dependents: task.batch.size, starting.timestamp, bucket.listing.max.objects.threshold, topic.regex.list, partitioner.class, partition.field.name, path.format
topic.regex.list

A comma-separated list of pairs of type <kafka topic>:<regex> that is used to map file paths to Kafka topics. An example might be topic1:.*\.json to source all files ending in .json to a Kafka topic named topic1. You can specify multiple of these <kafka topic>:<regex> mappings to send different sets of files to different topics. Any files that aren’t mapped by a regex will be ignored and not sourced. Files that match multiple mappings will be sent to the first topic in the list that maps the file.

  • Type: list
  • Default: “”
  • Valid Values: A list of pairs in the form <kafka topic1>:<regex1>, <kafka topic2>:<regex2>, ...
  • Importance: high
task.batch.size

The number of files assigned to each task at a time.

  • Type: int
  • Default: 10
  • Valid Values: [1,…,2000]
  • Importance: medium
file.discovery.starting.timestamp

A Unix timestamp that denotes where to start processing files. Any file encountered with a creation time earlier than this will be ignored.

  • Type: long
  • Default: 0
  • Valid Values: [0,…]
  • Importance: medium
bucket.listing.max.objects.threshold

An integer that represents the maximum number of objects the connector will index from the bucket at a time before failing. A value of -1 indicates no limit.

  • Type: int
  • Default: -1
  • Importance: medium

Connector Parameters

azblob.poll.interval.ms

Frequency, in milliseconds, to poll for new or removed folders. This may result in updated task configurations that start polling for data in added folders or stop polling for data in removed folders.

  • Type: long
  • Default: 300000
  • Importance: medium
format.class

Class responsible for converting storage objects to source records.

  • Type: class
  • Valid Values: Any class implementing: io.confluent.connect.cloud.storage.source.format.CloudStorageAvroFormat, io.confluent.connect.cloud.storage.source.format.CloudStorageJsonFormat, io.confluent.connect.cloud.storage.source.format.CloudStorageByteArrayFormat.
  • Importance: high
schema.cache.size

The size of the schema cache used in the Avro converter.

  • Type: int
  • Default: 50
  • Valid Values: [1,…]
  • Importance: low
record.batch.max.size

The maximum number of records to return each time storage is polled.

  • Type: int
  • Default: 200
  • Valid Values: [1,…]
  • Importance: medium

Auto topic creation

For more information about Auto topic creation, see Configuring Auto Topic Creation for Source Connectors.

Configuration properties accept regular expressions (regex) that are defined as Java regex.

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.

  • 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.

  • 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.

  • 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.

  • 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.

  • 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 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.

  • Type: property values
  • Default: Kafka broker value

Storage Parameters

store.url

The storage connection URL, if applicable. For example: https::\\<my-storage-account.blob.core.windows.net/mycontainer.

  • Type: string
  • Default: null
  • Importance: high
format.bytearray.extension

Output file extension for Byte Array Format. Defaults to .bin.

  • Type: string
  • Default: .bin
  • Importance: low
format.bytearray.separator

String inserted between records for ByteArrayFormat. Defaults to System.lineSeparator() and may contain escape sequences like \n. An input record that contains the line separator looks like multiple records in the storage object output.

  • Type: string
  • Default: null
  • Importance: low
topics.dir

Top level directory where data was stored to be re-ingested by Kafka.

  • Type: string
  • Default: topics
  • Importance: high
directory.delim

Directory delimiter pattern.

  • Type: string
  • Default: /
  • Importance: medium
behavior.on.error

Sets how the connector handles errors that occur when processing records.

  • Type: string
  • Default: fail
  • Valid Values: fail, ignore, log
  • Importance: medium

Partitioner Parameters (Backup and Restore Connector Only)

partition.field.name

The name of the partitioning field when FieldPartitioner is used.

  • Type: list
  • Default: “”
  • Importance: medium
path.format

This configuration that was used to set the format of the data directories when partitioning with a TimeBasedPartitioner. For example, if you set path.format to 'year'=YYYY/'month'=MM/'day'=dd/'hour'=HH, valid data directories are: /year=2015/month=12/day=07/hour=15/.

  • Type: string
  • Default: “”
  • Importance: medium
partitioner.class

The partitioner to use when reading data to the store.

  • Type: class
  • Default: io.confluent.connect.storage.partitioner.DefaultPartitioner
  • Importance: high

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,.... These servers are used only for the initial connection to discover the full cluster membership, which may change dynamically, so this list need not contain the full set of servers. You may want more than one, 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

Confluent license properties

You can put license-related properties in the connector configuration, or starting with Confluent Platform version 6.0, you can put license-related properties in the Connect worker configuration 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.

If you are a subscriber, contact Confluent Support for more information.

  • Type: string
  • Default: “”
  • Valid Values: Confluent Platform license
  • Importance: high
confluent.topic.ssl.truststore.location

The location of the trust store file.

  • 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.

  • 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.

  • 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.

  • 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.

  • 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.

  • Type: string
  • Default: “PLAINTEXT”
  • Importance: medium

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.

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 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:

    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:

    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.