7. Managing RDFox Servers¶

As explained in Section 4, each running RDFox instance contains a server object, which acts as a top-level container for all information stored in the instance. A server supports operations such as creating and deleting data stores, creating and deleting roles, and granting permissions to roles.

7.1. Server Parameters¶

When a server is instantiated, it can be given a number of parameters that govern various aspects of the server’s operation. All parameters are specified as key-value pairs. If an RDFox instance is started from the command line, the server parameters are passed as arguments to the RDFox (on Linux and macOS) or RDFox.exe (on Windows) executable as described in Section 15.1. If an RDFox instance is started from Java, the server parameters can be specified as arguments to the tech.oxfordsemantic.jrdfox.client.ConnectionFactory.startLocalServer() method; please refer to the Javadoc for more information. The following table describes all available server parameters.

Option	Value	Description
`log-calls`	`true` or `false`	If the value is `true`, all API calls are recorded in a script within the `api-log` subdirectory of the server directory that the shell can replay later. This can be useful for trouble-shooting. Default is `false`.
`max-memory`	an integer	Specifies the maximum of memory (in MB) that the RDFox instance is allowed to use. The default is 0.9 times the installed memory.
`num-threads`	an integer	Specifies the number of threads that the system will use for tasks such as reasoning and importation. The default is the number of logical processors available on the machine.
`license-content`	a string	Specifies the license content verbatim. This parameter is not set by default. See Section 2.4.3 for the precedence of license-related options.
`license-file`	a string	Specifies the path to the license file to use. The default value is `<server-directory>/RDFox.lic`. See Section 2.4.3 for the precedence of license-related options.
`server-directory`	a string	Specifies the server directory. A directory may only be used by one RDFox server at a time. The default value is `$HOME/.RDFox` on Linux/Mac, and `%LOCALAPPDATA%\RDFox` on Windows.
`persist-roles`	`file` or `off`	If the value is `file`, RDFox will persist roles, their privileges, and their memberships to a file in the server directory. Default value is `off` for JRDFox and depends on the mode for the RDFox executable.
`persist-ds`	`file` or `off`	If the value is `file`, data stores and their content will be incrementally saved (persisted) to files in the server directory. Must be `off` if `persist-roles` is `off`. Default value is `off` for JRDFox and depends on the mode for the RDFox executable.
`allowed-schemes-on-load`	a string containing a space-separated list of URI schemes	Specifies a space-separated list of schemes that are allowed to be used in the SPARQL 1.1 `LOAD` update. The default value is `https`.