gpkafka.yaml
gpkafka.yaml
gpkafka configuration file (version 1).
Synopsis
DATABASE: db_name USER: user_name PASSWORD: password HOST: host PORT: greenplum_port [VERSION: 1] KAFKA: INPUT: SOURCE: BROKERS: kafka_broker_host:broker_port [, ... ] TOPIC: kafka_topic [COLUMNS: - NAME: { column_name | __IGNORED__ } TYPE: column_data_type [ ... ]] FORMAT: data_format [[DELIMITED_OPTION: DELIMITER: delimiter_string] | [AVRO_OPTION: SCHEMA_REGISTRY_ADDR: http://schemareg_host:schemareg_port [, ... ]] | [CUSTOM_OPTION: NAME: udf_name PARAMSTR: udf_parameter_string]] [FILTER: filter_string] ERROR_LIMIT: { num_errors | percentage_errors } OUTPUT: [SCHEMA: output_schema_name] TABLE: table_name [MODE: mode] [MATCH_COLUMNS: - match_column_name [ ... ]] [UPDATE_COLUMNS: - update_column_name [ ... ]] [UPDATE_CONDITION: update_condition] [MAPPING: - NAME: target_column_name EXPRESSION: { source_column_name | expression } [ ... ] | target_column_name : { source_column_name | expression } [ ... ] ] [METADATA: [SCHEMA: metadata_schema_name]] COMMIT: MAX_ROW: num_rows MINIMAL_INTERVAL: wait_time [POLL: BATCHSIZE: num_records TIMEOUT: poll_time] [TASK: POST_BATCH_SQL: udf_or_sql_to_run BATCH_INTERVAL: num_batches] [PROPERTIES: kafka_property_name: kafka_property_value [ ... ]]
Description
You specify load configuration parameters for the gpkafka utilities in a YAML-formatted configuration file. (This reference page uses the name gpkafka.yaml when referring to this file; you may choose your own name for the file.) Load parameters include Greenplum Database connection and target table information, Kafka broker and topic information, and error and commit thresholds.
The gpkafka utility processes the YAML configuration file in order, using indentation (spaces) to determine the document hierarchy and the relationships between the sections. The use of white space in the file is significant, and keywords are case-sensitive.
Keywords and Values
- DATABASE: db_name
- The name of the Greenplum database.
- USER: user_name
- The name of the Greenplum Database user/role. This user_name must have permissions as described in the Greenplum Streaming Server documentation.
- PASSWORD: password
- The password for the Greenplum Database user/role.
- HOST: host
- The host name or IP address of the Greenplum Database master host.
- PORT: greenplum_port
- The port number of the Greenplum Database server on the master host.
- VERSION: 1
- Optional. The version of the gpkafka configuration file. The default version is Version 1.
- SOURCE
- Kafka input configuration parameters.
- BROKERS: kafka_broker_host:broker_port
- The host and port identifying the Kafka broker.
- TOPIC: kafka_topic
- The name of the Kafka topic from which to load data. The topic must exist.
- COLUMNS:
- The column names and data types. You must specify all Kafka data elements in the order in which they appear in the Kafka message. Optional when the column names and types match the target Greenplum Database table definition.
- The default source-to-target data mapping behaviour of gpkafka
is to match a column name as defined in COLUMNS:NAME with
a column name in the target Greenplum Database TABLE. You
can override the default mapping by specifying a MAPPING block.
- NAME: column_name
- The name of a column. column_name must match the column name of the target Greenplum Database table. Specify __IGNORED__ to omit this Kafka message data element from the load operation.
- TYPE: data_type
- The data type of the column. You must specify an equivalent data type for each non-ignored Kafka message data element and the associated Greenplum Database table column.
- FORMAT: data_format
- The format of the Kafka message value data. You may specify a FORMAT
of avro, binary, csv,
custom, delimited, or json.
- avro
- When you specify the avro data format, you must define only a single json type column in COLUMNS. If the Kafka message value schema is registered in a Confluent Schema Registry, you must also provide the AVRO_OPTION.
- binary
- When you specify the binary data format, you must define only a single bytea type column in COLUMNS.
- csv
- When you specify the csv data format, the message content cannot contain line ending characters (CR and LF).
- custom
- When you specify the custom data format, you must provide a CUSTOM_OPTION.
- delimited
- When you specify the delimited data format, you must provide a DELIMITED_OPTION.
- json
- When you specify the json data format, you must define only a single json type column in COLUMNS.
- AVRO_OPTION:SCHEMA_REGISTRY_ADDR: http://schemareg_host:schemareg_port
- Optional. When you specify avro as the FORMAT and the Avro schema of the JSON data you want to load is registered in the Confluent Schema Registry, you must identify the host name and port number of each Confluent Schema Registry server in your Kafka cluster. You may specify more than one address, and at least one of the addresses must be legal.
- CUSTOM_OPTION
- Optional. When you specify custom as the
FORMAT, CUSTOM_OPTION is
required. This block identifies the name and the arguments of a
custom formatter user-defined function.
- NAME: udf_name
- The name of the custom formatter user-defined function.
- PARAMSTR: udf_parameter_string
- A string specifying the comma-separated list of arguments to pass to the custom formatter user-defined function.
- DELIMITED_OPTION:DELIMITER: delimiter_string
- Optional. When you specify delimited as the FORMAT, delimiter_string is required and must identify the Kafka message data element delimiter. delimiter_string may be a multi-byte value, and up to 32 bytes in length. It may not contain quote and escape characters.
- FILTER: filter_string
- The filter to apply to the Kafka input messages before gpkafka loads the data into Greenplum Database. If the filter evaluates to true, gpkafka loads the message. If the filter evaluates to false, the message is dropped. filter_string must be a valid SQL conditional expression and may reference one or more COLUMNS names.
- ERROR_LIMIT: { num_errors | percentage_errors }
- The error threshold, specified as either an absolute number or a percentage. gpkafka load exits when this limit is reached.
- SCHEMA: output_schema_name
- The name of the Greenplum Database schema in which table_name resides. Optional, the default schema is the public schema.
- TABLE: table_name
- The name of the Greenplum Database table into which gpkafka loads the Kafka data.
- MODE: mode
- The table load mode. Valid mode values are INSERT, MERGE, or UPDATE. The default value is INSERT.
- UPDATE - Updates the target table columns that are listed in UPDATE_COLUMNS when the input columns identified in MATCH_COLUMNS match the named target table columns and the optional UPDATE_CONDITION is true. UPDATE is not supported if the target table column name is a reserved keyword, has capital letters, or includes any character that requires quotes (" ") to identify the column.
-
MERGE - Inserts new rows and updates existing
rows when:
- columns are listed in UPDATE_COLUMNS, and
- the MATCH_COLUMNS target table column values are equal to the input data.
Note: Due to limitations of stream ingestion, gpkafka cannot ensure that the single new row is created from the Kafka message with the latest offset.Use UPDATE_CONDITION to filter out the rows to discard. MERGE is not supported if the target table column name is a reserved keyword, has capital letters, or includes any character that requires quotes (" ") to identify the column. - MATCH_COLUMNS:
- Required if MODE is MERGE or UPDATE.
- match_column_name
- Specifies the column(s) to use as the join condition for the update. The attribute value in the specified target column(s) must be equal to that of the corresponding source data column(s) in order for the row to be updated in the target table.
- UPDATE_COLUMNS:
- Required if MODE is MERGE or UPDATE.
- update_column_name
- Specifies the column(s) to update for the rows that meet the MATCH_COLUMNS criteria and the optional UPDATE_CONDITION.
- UPDATE_CONDITION: update_condition
- Optional. Specifies a boolean condition, similar to that which you would declare in a WHERE clause, that must be met in order for a row in the target table to be updated (or inserted, in the case of a MERGE).
- MAPPING:
- Optional. Overrides the default source-to-target column mapping. gpkafka supports two mapping syntaxes.
-
Note: When you specify a MAPPING, ensure that you provide a mapping for all Kafka data elements of interest. gpkafka does not automatically match column names when you provide a MAPPING.
- NAME: target_column_name
- Specifies the target Greenplum Database table column name.
- EXPRESSION: { source_column_name | expression }
- Specifies a Kafka COLUMNS:NAME (source_column_name) or an expression. When you specify an expression, you may provide a value expression that you would specify in the SELECT list of a query, such as a constant value, a column reference, an operator invocation, a built-in or user-defined function call, and so on.
- target_column_name: { source_column_name | expression }
- When you use this MAPPING syntax, specify the target_column_name and {source_column_name | expression} as described above.
- SCHEMA: metadata_schema_name
- The name of the Greenplum Database schema in which gpkafka creates external and history tables. The default metadata_schema_name is KAFKA:OUTPUT:SCHEMA.
- COMMIT:
- Controls how gpkafka load commits data to Greenplum
Database. You must specify one of MAX_ROW or
MINIMAL_INTERVAL. You may specify both configuration parameters
as long as both values are not zero (0). Try setting
and tuning MINIMAL_INTERVAL to your environment;
introduce a MAX_ROW setting only if you encounter
high memory usage associated with message buffering.
- MAX_ROW: number_of_rows
- The number of rows to batch before triggering an INSERT operation on the Greenplum Database table. The default value of MAX_ROW is 0, which instructs gpkafka to ignore this commit trigger condition.
- MINIMAL_INTERVAL: wait_time
- The minimum amount of time to wait (milliseconds) between each INSERT operation on the table. The default value is 0, wait forever.
- POLL:
- Controls the polling time period and batch size when reading Kafka data.
- BATCHSIZE: num_records
- The number of Kafka records in a batch. BATCHSIZE must be smaller than COMMIT:MAX_ROW. The default batch size is 200.
- TIMEOUT: poll_time
- The maximum time, in milliseconds, to wait in a polling cycle if Kafka data is not available. You must specify a TIMEOUT greater than 100 milliseconds and less than COMMIT:MINIMAL_INTERVAL. The default poll timeout is 1000 milliseconds.
- TASK:
- Controls the execution and scheduling of a periodic (maintenance) task.
- POST_BATCH_SQL: udf_or_sql_to_run
- The user-defined function or SQL command(s) that you want to run after the specified number of batches are read from Kafka. The default is null.
- BATCH_INTERVAL: num_batches
- The number of batches to read before executing udf_or_sql_to_run. The default batch interval is 0.
- PROPERTIES:
- Kafka consumer configuration property names and values.
- kafka_property_name
- The name of a Kafka property.
- kafka_property_value
- The Kafka property value.
Notes
If you created a database object name using a double-quoted identifier (delimited identifier), you must specify the delimited name within single quotes in the gpkafka.yaml configuration file. For example, if you create a table as follows:
CREATE TABLE "MyTable" ("MyColumn" text);
Your gpkafka.yaml YAML configuration file would refer to the above table and column names as:
COLUMNS: - name: '"MyColumn"' type: text OUTPUT: TABLE: '"MyTable"'
PROPERTIES: api.version.request: false broker.version.fallback: 0.8.2.1
Examples
Load data from Kafka as defined in the Version 1 configuration file named kafka2greenplum.yaml:
gpkafka load kafka2greenplum.yaml
Example kafka2greenplum.yaml configuration file:
DATABASE: ops USER: gpadmin HOST: mdw-1 PORT: 5432 KAFKA: INPUT: SOURCE: BROKERS: kbrokerhost1:9092 TOPIC: customer_expenses COLUMNS: - NAME: cust_id TYPE: int - NAME: month TYPE: int - NAME: expenses TYPE: decimal(9,2) FORMAT: delimited DELIMITED_OPTION: DELIMITER: '|' ERROR_LIMIT: 25 OUTPUT: SCHEMA: payables TABLE: expenses MAPPING: - NAME: customer_id EXPRESSION: cust_id - NAME: newcust EXPRESSION: cust_id > 5000000 - NAME: expenses EXPRESSION: expenses - NAME: tax_due EXPRESSION: expenses * .0725 METADATA: SCHEMA: gpkafka_internal COMMIT: MINIMAL_INTERVAL: 2000
See Also
gpkafka-v2.yaml, gpkafka history, gpkafka load, gpss, gpss.json