Configuration: Persistence

The persistence module allows the transformer to store data in a datastore. The default configuration makes the module load up an in-process sqlite3 database and stores data into a file that can be configured via the persistence.conf configuration file.

For production environments that use a transformer cluster it is advised not to use the sqlite3/filedb persistence as it does not synchronize it's state over the cluster. It is recommended to use the javadb/jdbc layer and connect the persistence module of all transformers in the cluster to a central Database.

Loading Persistence

To load the persitence module add the following to transformer.conf

add-module  persistence 

Options

persistence-filedb-bootstrap

Type: String Array
Default: None

Array of SQL files to be executed when the module loads. This option is only available if enable-file-database is set to true

enable-file-database

Type: Boolean
Default: FALSE

Turn on or off file DB, only when this config option is set to false file database will be disabled

persistence-classid

Type: String
Default: None

When enable-file-database is set to false this option specifies the classid of the java persistence adapter to be loaded and used as a bridge between transformer and a database

Configuration group add-database-params

Start a database params configuration group. This config group gets passed into the persistence implementation loaded and can be used for custom java persistence adapters.

Format:

add-database-params
    init-string         [value]
    driver-name         [value]
    username            [value]
    password            [value]
    extra-params        [values]
end-database-paarms

extra-params

Type: String Array
Default: None

Array of extra arguments to be passed into a custom java persistence adapters. In case of the default Jdbc implementation this takes exactly one argument of type int and specifies the size of the connection pool to be used

init-string

Type: String
Default: None

Initialisation string for the database. For File/SQLite DB this specifies the location where the database file should be stored, for the default JDBC implementation this specifies the JDBC URL.

driver-name

Type: String
Default: None

The Jdbc driver name of the driver to be used by the JDBC default implementation. The driver needs to be made available to transformer.

username

Type: String
Default: None

The username required to authenticate with the database

password

Type: String
Default: None

The password required to authenticate with the database

logfile

Type: String
Default: persistence.log

Logfile

log-level

Type: String
Default: INFO

Logging level of the persistence module.