A SWISH (SWI-Prolog for SHaring) docker

This repository provides a Docker image for SWISH based on the official SWI-Prolog docker image.

Building the image

The image is built by running

make image

Running the image

The image may be used in many configurations, both controlled by docker options and options to the entry point. As basic operation typically already requires publishing ports and setting up a volume for the data, we added a bash script swish.sh that automates the common scenarios by providing docker run options from defaults and provided options. When called with -n, as in ./swish.sh -n option ..., it merery prints the docker command it will execute. The following options are processed:

• --port=N
  Modify the -p option to -p N:3050. Default is 3050.
• --data=dir
  Mount the given directory as data. Default is the working directory.
• --with-R[=from]
  Add --volumes-from from where from defaults to rserve to connect to an R docker image
• -n
  Just print the docker command that will be executed.
• -d
  Detach from the terminal
• -it
  Pass on (interactive)

All remaining options are passed to the entry point of the image.

Data

The docker image maintains its data (user programs and configuration) on the volume /data. This may be mapped to a host directory using the docker -v options (see also the --data=dir option of swish.sh).

Within the data directory, SWISH manages the following items:

• config-enabled is a directory where the configuration is stored. If it doesn't exist it is created and filled with a default configuration that depends on the provided options. The directory and its files have the same owner and group as the root of the managed volume.

• data is the directory where all dynamic user data is maintained. If the directory exists, the SWISH server is started with the user and group of the directory. If it doesn't exist the directory is created as owned by daemon.daemon and the server is started with these credentials.

• https If the --https option is passed, it creates or reuses this directory and the files server.crt and server.key. The created certificate is self-signed.

• passwd If authenticated mode is enabled, this file maintains the users and password hashes.

Network access

The container creates a server at port 3050. By default this is an HTTP server. If run <docker options> swish --https is used, an HTTPS server is started.

The entry point

The entry point of the containser is /entry.sh, a shell script that initialises the data volume if needed and starts the server. It accepts the following options:

• --bash
  Instead of starting the server, start a bash shell. Terminate after bash completes.

• --help
  Emit short help.

Configuration

The SWISH configuration is controlled by files in the config-enabled directory. Several commands may be used to control the configuration. These are executed as below:

docker run -it swish option ...

Multiple configuration options may be passed to update multiple facets of the configuration. Normally the image stops after updating the configuration. If --run is added the entry point starts the server after updating the configuration.

The options provided are:

• --list-config
  List installed and available configuration items. If an item is installed, indicate whether it is modified.

• --auth=type
  Change the configured authentication scheme. This is one of

  • always
    Run in fully authenticated mode, forcing the user to login and allowing to execute arbitrary commands. When executed for the first time, docker must be run interactively (run -it) to create the first user. Additional users are created using

    docker run -it swish --add-user.

  • social
    Use social login. By default enables optional http login, login using google and stackoverflow. Both need to be further configured by editing config-enabled/auth_google.pl and config-enabled/auth_stackoverflow.pl

  • anon (or anonymous)
    This is the initial default, providing fully anonymous login, executing only sandboxed Prolog queries.

• --add-config file ...
  Add one or more configuration files by copying them from the available configuration directory.

• --add-user
  Add a new user to the HTTP authentication. Prompts for user name, email, group (unused, use users) and password.

• --https
  Create an HTTPS server. This uses the certificate from the https directory (see above). If no certificate exists, a self-signed certificate is created. The details may be refined using --CN=host, --O=organization and --C=country