Wiki farms

What is a wiki farm?

A wiki farm is a single Canasta installation that hosts multiple wikis. All wikis in a farm share the same MediaWiki software, Docker containers, Caddy reverse proxy, and can share global PHP settings, extensions, and skins. At the same time, each wiki has its own:

Database — a separate MariaDB database named after the wiki ID
Image directory — uploaded files are stored per-wiki
Settings — each wiki can have its own PHP settings files and can enable or disable extensions and skins independently
Admin account — each wiki gets its own admin user and password

This makes wiki farms useful when you want to run several related wikis without the overhead of separate Docker stacks for each one, while still being able to configure each wiki individually where needed.

Even a single-wiki Canasta installation uses the same underlying architecture — it is simply a farm with one wiki. See General concepts for details on installation structure, wiki IDs, settings, and other topics that apply to all installations.

How wiki farm URLs work

Each wiki in a farm is identified by its URL, which determines how users reach it. The URL is set when you create or add a wiki and is stored in config/wikis.yaml.

Path-based wikis

Multiple wikis share the same domain, distinguished by URL path. The first wiki in the farm is created with canasta create and gets the root path. Additional wikis are added with canasta add using a domain/path URL:

# Create the farm with the first wiki at the root
canasta create -i myfarm -w mainwiki -n example.com
# Add a second wiki at example.com/docs
canasta add -i myfarm -w docs -u example.com/docs
# Add a third wiki at example.com/internal
canasta add -i myfarm -w internal -u example.com/internal

Users access these at https://example.com, https://example.com/docs, and https://example.com/internal.

Subdomain-based wikis

Each wiki uses a different subdomain. This requires DNS records pointing each subdomain to your Canasta server. Caddy handles SSL/HTTPS automatically for all configured domains.

canasta create -i myfarm -w mainwiki -n wiki.example.com
canasta add -i myfarm -w docs -u docs.example.com
canasta add -i myfarm -w community -u community.example.com

Mixed

You can combine both approaches:

canasta create -i myfarm -w mainwiki -n example.com
canasta add -i myfarm -w docs -u example.com/docs
canasta add -i myfarm -w community -u community.example.com

Managing a wiki farm

Viewing wikis

canasta list

Example output:

Canasta ID  Wiki ID  Server Name  Server Path  Installation Path       Orchestrator
myfarm      mainwiki example.com  /            /home/user/myfarm       compose
myfarm      docs     example.com  /docs        /home/user/myfarm       compose
myfarm      community community.example.com / /home/user/myfarm       compose

Per-wiki extension and skin management

Use the -w flag to target a specific wiki:

canasta extension enable SemanticMediaWiki -i myfarm -w docs
canasta skin enable CologneBlue -i myfarm -w community

Without -w, the command applies to all wikis in the farm.

Removing a wiki

canasta remove -i myfarm -w community

This deletes the wiki's database and configuration. You will be prompted for confirmation.

Deleting the entire farm

canasta delete -i myfarm

This stops and removes all containers, volumes, and configuration files.

Wiki directory

When a user browses to an unrecognized path on a wiki farm, Canasta returns a styled 404 page. You can optionally enable a wiki directory on this page, which displays a card grid of all wikis in the farm with links and logos.

The directory is disabled by default for security — enabling it publicly exposes the list of wikis in your farm.

Enabling the directory

canasta config set CANASTA_ENABLE_WIKI_DIRECTORY=true -i myfarm

After the instance restarts, the 404 page will show an "Available wikis" section with a card for each wiki. The directory is also available as a standalone landing page at the /wikis path (e.g. https://example.com/wikis).

Disabling the directory

canasta config set CANASTA_ENABLE_WIKI_DIRECTORY=false -i myfarm

How logos work

Each wiki card attempts to load the wiki's logo by querying its MediaWiki API. If a wiki is private, unreachable, or does not have a logo configured, the card simply appears without a logo — no errors are shown.

See the CLI Reference for the full list of commands and flags.

Help:Wiki farms

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