Redis

The Redis target writes data to Redis. For information about supported versions, see Supported systems and versions.

When you configure the target, you specify the mode that the target uses to process records. You configure properties to connect to Redis, including the URI of the Redis server.

In batch mode, the Redis target can use CRUD operations defined in the sdc.operation.type record header attribute to process data. When CRUD operations are not specified in a record, the target treats it like an Upsert record. For information about Data Collector change data processing and a list of CDC-enabled sources, see Processing changed data.

Mode

The Redis target writes data to Redis using one of the following modes:

Batch mode

In batch mode, the target writes data to Redis key-value pairs. You configure each key-value pair by selecting the incoming fields to use as the key and the value. You also select the data type of the Redis value. You can configure the target to write to multiple key-value pairs.

For example, you are processing records that contain a String city field and a Map latitude_longitude field. Let’s assume that one record contains the following data:

city: {String} "San Francisco"
latitude_longitude: {Map}
    latitude: {String} "37.7749"
    longitude: {String} "-122.4194"

You select the city field as the Redis key, and the latitude_longitude field as the Redis value. Data Collector can convert the Map data type to the Redis Hash data type, so you select Hash for the data type of the Redis value, as follows:

Field properties showing the Data Type set to Hash

When you run the flow, the Redis target writes the key "San Francisco" to Redis with a Hash value containing the latitude and longitude.

Publish mode

In publish mode, the target publishes data as messages to a Redis channel. You specify the channel to use and the data format of the messages. The publish mode pushes each record as one message to the specified Redis channel.

Data types for batch mode

When you configure the target for batch mode, you select the incoming fields to use as the Redis key and value. You also select the data type of the Redis value. If needed, the Redis target converts the Data Collector data type of the incoming value field to the selected Redis data type.

When appropriate, use a Field Type Converter processor earlier in the flow to convert data types.

The following table lists the Data Collector data types that can be converted to Redis data types:

Data Collector Data Type	Redis Data Type
String	String
List	List or Set
Map	Hash

Note: The remaining Data Collector and Redis data types are not supported.

Data formats for publish mode

When you configure the target for publish mode, the target publishes messages to Redis based on the data format that you select. You can use the following data formats:

Avro

The stage writes records based on the Avro schema. You can use one of the following methods to specify the location of the Avro schema definition:

In Flow Configuration - Use the schema that you provide in the stage configuration.
In Record Header - Use the schema included in the avroSchema record header attribute.
Confluent Schema Registry - Retrieve the schema from Confluent Schema Registry. The Confluent Schema Registry is a distributed storage layer for Avro schemas. You can configure the target to look up the schema in the Confluent Schema Registry by the schema ID or subject.
If using the Avro schema in the stage or in the record header attribute, you can optionally configure the stage to register the Avro schema with the Confluent Schema Registry. You can also optionally include the schema definition in the message. Omitting the schema definition can improve performance, but requires the appropriate schema management to avoid losing track of the schema associated with the data.

You can include the Avro schema in the output.

You can also compress data with an Avro-supported compression codec. When using Avro compression, avoid configuring any other compression properties in the stage.

Binary

The stage writes binary data to a single field in the record.

Delimited

The target writes records as delimited data. When you use this data format, the root field must be list or list-map.

You can use the following delimited format types:

Default CSV - File that includes comma-separated values. Ignores empty lines in the file.
RFC4180 CSV - Comma-separated file that strictly follows RFC4180 guidelines.
MS Excel CSV - Microsoft Excel comma-separated file.
MySQL CSV - MySQL comma-separated file.
Tab-Separated Values - File that includes tab-separated values.
PostgreSQL CSV - PostgreSQL comma-separated file.
PostgreSQL Text - PostgreSQL text file.
Custom - File that uses user-defined delimiter, escape, and quote characters.
Multi Character Delimited - File that uses multiple user-defined characters to delimit fields and lines, and single user-defined escape and quote characters.

JSON

The target writes records as JSON data. You can use one of the following formats:

Array - Each file includes a single array. In the array, each element is a JSON representation of each record.
Multiple objects - Each file includes multiple JSON objects. Each object is a JSON representation of a record.

Protobuf

Writes one record in a message. Uses the user-defined message type and the definition of the message type in the descriptor file to generate the message.

For information about generating the descriptor file, see Protobuf data format prerequisites.

SDC Record

The target writes records in the SDC Record data format.

Text

The target writes data from a single text field to the target system. When you configure the stage, you select the field to use.

You can configure the characters to use as record separators. By default, the target uses a UNIX-style line ending (\n) to separate records.

When a record does not contain the selected text field, the target can report the missing field as an error or to ignore the missing field. By default, the target reports an error.

When configured to ignore a missing text field, the target can discard the record or write the record separator characters to create an empty line for the record. By default, the target discards the record.

Define the CRUD operation

When using the Redis target in batch mode, you can use CRUD operations to write to Redis. To use CRUD operations, define the CRUD operation record header attribute for each record earlier in the flow. Records without the attribute defined are treated as Upsert: new records are written and existing records are updated.

To use CRUD operations to write records, set the following CRUD operation record header attribute:

sdc.operation.type

When defined, the Redis target uses the CRUD operation in the sdc.operation.type record header attribute when writing to Redis. The target supports the following values for the sdc.operation.type attribute:

1 for INSERT
2 for DELETE
3 for UPDATE
4 for UPSERT

If your flow has a CRUD-enabled source that processes changed data, the target simply reads the operation type from the sdc.operation.type header attribute that the source generates. If your flow has a non-CDC source, you can use the Expression Evaluator processor or a scripting processor to define the record header attribute. For more information about Data Collector changed data processing and a list of CDC-enabled sources, see Processing changed data.

Configuring a Redis target

About this task

Configure a Redis target to write data to Redis.

Procedure

In the Properties panel, on the General tab, configure the following properties:

General Property	Description
Name	Stage name.
Description	Optional description.
Stage Library	Library version that you want to use.
Required Fields	Fields that must include data for the record to be passed into the stage. Tip: You might include fields that the stage uses. Records that do not include all required fields are processed based on the error handling configured for the flow.
Preconditions	Conditions that must evaluate to TRUE to allow a record to enter the stage for processing. Click Add to create additional preconditions. Records that do not meet all preconditions are processed based on the error handling configured for the stage.
On Record Error	Error record handling for the stage: Discard - Discards the record. Send to Error - Sends the record to the flow for error handling. Stop Flow - Stops the flow.

On the Redis tab, configure the following properties:

Redis Property	Description
URI	URI of the Redis server. Use the following format: `redis://<host name>:<port number>/<database>` You can omit the database if the server uses the default database. You can optionally include your password to log in to the Redis server. For example: `redis://:<password>@<host name>:<port number>/<database>`
Mode	Mode used to write to Redis: Batch - Writes data to Redis key-value pairs. In batch mode, you can use the CRUD operation header attribute to determine how the target writes data to Redis. Publish - Publishes data as messages to a Redis channel. Default is Batch.
Key	Incoming field to use for the Redis key. Used in batch mode only.
Value	Incoming field to use for the Redis value. Used in batch mode only.
Data Type	Data type of the Redis value. Used in batch mode only. Default is String.
Channel	Redis channel to publish the messages to. Used in publish mode only.
Connection Timeout (sec)	Maximum time in seconds to wait for a connection. Default is 1000 seconds.

When using Publish mode, on the Data Format tab, configure the following property:

Data Format Property	Description
Data Format	Data format of the data: Avro Binary Delimited JSON Protobuf SDC Record Text

For Avro data, on the Data Format tab, configure the following properties:

Avro Property	Description
Avro Schema Location	Location of the Avro schema definition to use when writing data: In Flow Configuration - Use the schema that you provide in the stage configuration. In Record Header - Use the schema in the avroSchema record header attribute. Use only when the avroSchema attribute is defined for all records. Confluent Schema Registry - Retrieve the schema from Confluent Schema Registry.
Avro Schema	Avro schema definition used to write the data. You can optionally use the `runtime:loadResource` function to load a schema definition stored in a runtime resource file.
Register Schema	Registers a new Avro schema with Confluent Schema Registry.
Schema Registry URLs	Confluent Schema Registry URLs used to look up the schema or to register a new schema. To add a URL, click Add and then enter the URL in the following format: `http://<host name>:<port number>`
Basic Auth User Info	User information needed to connect to Confluent Schema Registry when using basic authentication. Enter the key and secret from the `schema.registry.basic.auth.user.info` setting in Schema Registry using the following format: `<key>:<secret>` Tip: To secure sensitive information such as user names and passwords, you can use runtime resources or credential stores.
Look Up Schema By	Method used to look up the schema in Confluent Schema Registry: Subject - Look up the specified Avro schema subject. Schema ID - Look up the specified Avro schema ID.
Schema Subject	Avro schema subject to look up or to register in Confluent Schema Registry. If the specified subject to look up has multiple schema versions, the stage uses the latest schema version for that subject. To use an older version, find the corresponding schema ID, and then set the Look Up Schema By property to Schema ID.
Schema ID	Avro schema ID to look up in Confluent Schema Registry.
Include Schema	Includes the schema in each message. Note: Omitting the schema definition can improve performance, but requires the appropriate schema management to avoid losing track of the schema associated with the data.
Avro Compression Codec	The Avro compression type to use. When using Avro compression, do not enable other compression available in the target.

For binary data, on the Data Format tab, configure the following property:

Binary Property	Description
Binary Field Path	Field that contains the binary data.

For delimited data, on the Data Format tab, configure the following properties:

Delimited Property	Description
Delimiter Format	Format for delimited data: Default CSV - File that includes comma-separated values. Ignores empty lines in the file. RFC4180 CSV - Comma-separated file that strictly follows RFC4180 guidelines. MS Excel CSV - Microsoft Excel comma-separated file. MySQL CSV - MySQL comma-separated file. Tab-Separated Values - File that includes tab-separated values. PostgreSQL CSV - PostgreSQL comma-separated file. PostgreSQL Text - PostgreSQL text file. Custom - File that uses user-defined delimiter, escape, and quote characters.
Header Line	Indicates whether to create a header line.
Delimiter Character	Delimiter character for a custom delimiter format. Select one of the available options or use Other to enter a custom character. You can enter a Unicode control character using the format \uNNNN, where N is a hexadecimal digit from the numbers 0-9 or the letters A-F. For example, enter \u0000 to use the null character as the delimiter or \u2028 to use a line separator as the delimiter. Default is the pipe character ( \| ).
Record Separator String	Characters to use to separate records. Use any valid Java string literal. For example, when writing to Windows, you might use `\r\n` to separate records. Available when using a custom delimiter format.
Escape Character	Escape character for a custom delimiter format. Select one of the available options or use Other to enter a custom character. Default is the backslash character ( \ ).
Quote Character	Quote character for a custom delimiter format. Select one of the available options or use Other to enter a custom character. Default is the quotation mark character ( " ).
Replace New Line Characters	Replaces new line characters with the configured string. Recommended when writing data as a single line of text.
New Line Character Replacement	String to replace each new line character. For example, enter a space to replace each new line character with a space. Leave empty to remove the new line characters.
Charset	Character set to use to write data.

For JSON data, on the Data Format tab, configure the following properties:

JSON Property	Description
JSON Content	Method to write JSON data: JSON Array of Objects - Each file includes a single array. In the array, each element is a JSON representation of each record. Multiple JSON Objects - Each file includes multiple JSON objects. Each object is a JSON representation of a record.
Charset	Character set to use to write data.

For protobuf data, on the Data Format tab, configure the following properties:

Protobuf Property	Description
Protobuf Descriptor File	Descriptor file (.desc) to use. The descriptor file must be in the Data Collector resources directory, `$SDC_RESOURCES`. For information about generating the descriptor file, see Protobuf data format prerequisites.
Message Type	Fully-qualified name for the message type to use when writing data. Use the following format: `<package name>.<message type>`. Use a message type defined in the descriptor file.

For text data, on the Data Format tab, configure the following properties:

Text Property	Description
Text Field Path	Field that contains the text data to be written. All data must be incorporated into the specified field.
Record Separator	Characters to use to separate records. Use any valid Java string literal. For example, when you write to Windows, you might use `\r\n` to separate records. By default, the target uses `\n`.
On Missing Field	When a record does not include the text field, determines whether the target reports the missing field as an error or ignores the missing field.
Insert Record Separator if No Text	When configured to ignore a missing text field, inserts the configured record separator string to create an empty line. When not selected, discards records without the text field.
Charset	Character set to use to write data.