flink-faker is an Apache Flink table source that generates fake data based on the Data Faker expression provided for each column.
Checkout this demo web application for some example Java Faker (fully compatible with Data Faker) expressions and Data Faker documentation.
This project is inspired by voluble.
mvn clean package
Flink Version | flink-faker Version |
---|---|
1.11 | 0.1.x - 0.4.x |
1.12 | 0.1.x - 0.4.x |
1.13 | 0.1.x - 0.4.x |
1.14 | 0.1.x - 0.4.x |
1.15 | 0.5.x |
There are no automated tests that check this compatibility. So, please treat this table as "best knowledge". If you notice any incompatibilities please open an issue.
- Download Flink from the Apache Flink website.
- Download the flink-faker JAR from the Releases page (or build it yourself).
- Put the downloaded jars under
lib/
. - (Re)Start a Flink cluster.
- (Re)Start the Flink CLI.
CREATE TEMPORARY TABLE heros (
`name` STRING,
`power` STRING,
`age` INT
) WITH (
'connector' = 'faker',
'fields.name.expression' = '#{superhero.name}',
'fields.power.expression' = '#{superhero.power}',
'fields.power.null-rate' = '0.05',
'fields.age.expression' = '#{number.numberBetween ''0'',''1000''}'
);
SELECT * FROM heros;
CREATE TEMPORARY TABLE location_updates (
`character_id` INT,
`location` STRING,
`proctime` AS PROCTIME()
)
WITH (
'connector' = 'faker',
'fields.character_id.expression' = '#{number.numberBetween ''0'',''100''}',
'fields.location.expression' = '#{harry_potter.location}'
);
CREATE TEMPORARY TABLE characters (
`character_id` INT,
`name` STRING
)
WITH (
'connector' = 'faker',
'fields.character_id.expression' = '#{number.numberBetween ''0'',''100''}',
'fields.name.expression' = '#{harry_potter.characters}'
);
SELECT
c.character_id,
l.location,
c.name
FROM location_updates AS l
JOIN characters FOR SYSTEM_TIME AS OF proctime AS c
ON l.character_id = c.character_id;
Currently, the faker
source supports the following data types:
CHAR
VARCHAR
STRING
TINYINT
SMALLINT
INTEGER
BIGINT
FLOAT
DOUBLE
DECIMAL
BOOLEAN
TIMESTAMP
DATE
ARRAY
MAP
MULTISET
ROW
Connector Option | Default | Description |
---|---|---|
number-of-rows |
None | The number of rows to produce. If this is options is set, the source is bounded otherwise it is unbounded and runs indefinitely. |
rows-per-second |
10000 | The maximum rate at which the source produces records. |
fields.<field>.expression |
None | The Data Faker expression to generate the values for this field. |
fields.<field>.null-rate |
0.0 | Fraction of rows for which this field is null |
fields.<field>.length |
1 | Size of array, map or multiset |
For rows of type TIMESTAMP
, DATE
the corresponding Java Faker expression needs to return a timestamp formatted as uuuu-MM-dd hh:mi:ss[.nnnnnnnnn]
.
Typically, you would use one of the following expressions:
CREATE TEMPORARY TABLE timestamp_and_date_example (
`timestamp1` TIMESTAMP(3),
`timestamp2` TIMESTAMP(3),
`timestamp3` TIMESTAMP(3),
`date1` DATE,
`date2` DATE
)
WITH (
'connector' = 'faker',
'fields.timestamp1.expression' = '#{date.past ''15'',''SECONDS''}',
'fields.timestamp2.expression' = '#{date.past ''15'',''5'',''SECONDS''}',
'fields.timestamp3.expression' = '#{date.future ''15'',''5'',''SECONDS''}',
'fields.date1.expression' = '#{date.birthday}',
'fields.date2.expression' = '#{date.birthday ''1'',''100''}'
);
SELECT * FROM timestamp_and_date_example;
For timestamp1
Java Faker will generate a random timestamp that lies at most 15 seconds in the past.
For timestamp2
Java Faker will generate a random timestamp, that lies at most 15 seconds in the past, but at least 5 seconds.
For timestamp3
Java Faker will generate a random timestamp, that lies at most 15 seconds in the future, but at least 5 seconds.
For date1
Java Faker will generate a random birthday between 18 and 65 years ago.
For date2
Java Faker will generate a random birthday between 1 and 100 years ago.
The usage of ARRAY
, MULTISET
, MAP
and ROW
types is shown in the following example.
CREATE TEMPORARY TABLE hp (
`character-with-age` MAP<STRING,INT>,
`spells` MULTISET<STRING>,
`locations` ARRAY<STRING>,
`house-points` ROW<`house` STRING, `points` INT>
) WITH (
'connector' = 'faker',
'fields.character-with-age.key.expression' = '#{harry_potter.character}',
'fields.character-with-age.value.expression' = '#{number.numberBetween ''10'',''100''}',
'fields.character-with-age.length' = '2',
'fields.spells.expression' = '#{harry_potter.spell}',
'fields.spells.length' = '5',
'fields.locations.expression' = '#{harry_potter.location}',
'fields.locations.length' = '3',
'fields.house-points.house.expression' = '#{harry_potter.house}',
'fields.house-points.points.expression' = '#{number.numberBetween ''10'',''100''}'
);
SELECT * FROM hp;
Datafaker allows to pick a random value from a list of options via expression Options.option
CREATE TEMPORARY TABLE orders (
`order_id` INT,
`order_status` STRING
)
WITH (
'connector' = 'faker',
'fields.order_id.expression' = '#{number.numberBetween ''0'',''100''}',
'fields.order_status.expression' = '#{Options.option ''RECEIVED'',''SHIPPED'',''CANCELLED'')}'
);
SELECT * FROM orders;
Copyright © 2020-2022 Konstantin Knauf
Distributed under Apache License, Version 2.0.