Databases configuration

First, you need to configure Kestra to use a database for its Queue and Repository:

kestra:
  queue:
    type: mysql
  repository:
    type: mysql

Minimal examples

The most important thing is to configure the way Kestra connect to a database. For now, Kestra support PostgreSQL and MySQL.

Here is a minimal MySQL configuration example :

datasources:
  mysql:
    url: jdbc:mysql://local:3306/kestra
    driverClassName: com.mysql.cj.jdbc.Driver
    username: kestra
    password: k3str4
    dialect: MYSQL

Here is minimal PostgreSQL configuration:

datasources:
  postgres:
    url: jdbc:postgresql://local:5432/kestra
    driverClassName: org.postgresql.Driver
    username: kestra
    password: k3str4

datasources.* properties

Since Kestra is built upon Micronaut (opens new window) and HikariCP (opens new window), many configurations are available in order to configure the database pool:

Properties	Type	Description
url	String	Set the jdbc connection string.
catalog	String	Set the default schema name to be set on connections.
schema	String	Set the default catalog name to be set on connections.
username	String	Set the default username used.
password	String	Set the default password to use.
transaction-isolation	String	Set the default transaction isolation level.
pool-name	String	Set the name of the connection pool.
connection-init-sql	String	Set the SQL string that will be executed on all new connections when they are created, before they are added to the pool.
connection-test-query	String	Set the SQL query to be executed to test the validity of connections.
connection-timeout	Long	Set the maximum number of milliseconds that a client will wait for a connection from the pool.
idle-timeout	Long	This property controls the maximum amount of time (in milliseconds) that a connection is allowed to sit idle in the pool.
minimum-idle	Long	The property controls the minimum number of idle connections that HikariCP tries to maintain in the pool, including both idle and in-use connections.
initialization-fail-timeout	Long	Set the pool initialization failure timeout.
leak-detection-threshold	Long	This property controls the amount of time that a connection can be out of the pool before a message is logged indicating a possible connection leak.
maximum-pool-size	Int	The property controls the maximum size that the pool is allowed to reach, including both idle and in-use connections.
max-lifetime	Long	This property controls the maximum lifetime of a connection in the pool.
validation-timeout	Long	Sets the maximum number of milliseconds that the pool will wait for a connection to be validated as alive.

Queues configuration

kestra.jdbc.queues

Kestra queues based on database simulate queues doing long polling. It queries a queues table to detect new messages. Change these parameters to reduce the latency (but increase load on the database).

• kestra.jdbc.queues.min-poll-interval: is the minimum duration between 2 polls
• kestra.jdbc.queues.max-poll-interval: is the maximum duration between 2 polls
• kestra.jdbc.queues.poll-switch-interval: is the duration when no message are received switching from min polling to max polling (ex: one message received, the min-poll-interval is used, if no new message arrived with poll-switch-interval, we switch to max-poll-interval).

kestra:
  jdbc:
    queues:
      min-poll-interval: 100ms
      max-poll-interval: 1000ms
      poll-switch-interval: 5s

kestra.jdbc.cleaner

Kestra cleans the queues table to avoid infinite grow of this table. You can control how often you want this cleaning to happen, and how long we will keep messages in the queue with retention.

kestra:
  jdbc:
    cleaner:
      initial-delay: 1h
      fixed-delay: 1h
      retention: 7d