At startup, SWISH reads *.pl files from the directory config-enabled. This directory is searched for in two places: the current working directory of the server and the SWISH source directory. If both exists the local one is used.

All files in config-enabled named *.pl are loaded alphabetical order using ensure_loaded/1. Changing the configuration typically requires a restart of the server. In a few cases this may be avoided by running ?- swish_app:load_config. or ?- make. Deciding whether or not a restart is needed requires knowledge of the internals of SWISH and the SWI-Prolog HTTP infra structure and the general advice is therefore to restart the server.

The directory config-available provides skeleton files for common configuration settings. These files may be linked from or copied to config-enabled.

The following authentication scenarios may be configured

• Without any authentication enabled, SWISH can be accessed without logging in and can only be used to execute safe goals.

• Using =auth_http_always.pl=, any access to SWISH requires authentication. This config module is not compatible with one of the other auth_* configuration modules.

• Load one or more of the auth_*.pl modules. This provides a Login button in the navigation bar. Note that the authentication modules require additional configuration.

• rlimit.pl supports limiting the memory (and optionally other resources) that can be used by the SWISH server.

A number of configuration modules contribute to enabling collaboration support such as managing users and get notifications.

• email.pl needs to be installed to enable notifications using mail. This module needs to be configured for contacting a mail gateway. Email also requires the GIT submodule pack/smtp to be checked out.

• notifications.pl and user_profile.pl need to be enabled to send notification and manage user profiles. The latter also requires the GIT submodule pack/profile to be checked out.

• network.pl is often needed to tell swish about the public HTTP host and port at which it is accessible. This is notably the case if proxies or tunnels are involved.

• The r_serve.pl config file provides R integration. See r_serve.pl for how to setup R itself for use with SWISH. R also requires the GIT submodule pack/rserve_client to be checked out and configured using

  ?- pack_rebuild(rserve_client).
  

• debug.pl provides several hints and tools to simplify server-side debugging of SWISH.

• logging.pl configures the creation of HTTP and Pengine log files.