SEO Module for CondationCMS

A CondationCMS module that provides SEO essentials: canonical URLs, robots meta tags, Open Graph, Twitter Cards, XML sitemap, and robots.txt.

Features

• Canonical URL generation with configurable query parameter handling
• Robots meta tag with per-node control and query-parameter-aware indexing rules
• Open Graph meta tags
• Twitter Card meta tags
• Sitemap index at /sitemap.xml, with separate sitemaps for pages and collections
• robots.txt at /robots.txt with hook-based extensibility

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Site Properties Configuration

All settings live in site.yaml (or the equivalent site properties file) under the seo.* namespace.

General

Key	Type	Default	Description
seo.canonical.enabled	boolean	true	Enable canonical URL output
seo.opengraph.enabled	boolean	true	Enable Open Graph meta tags
seo.twitter.enabled	boolean	true	Enable Twitter Card meta tags
seo.sitemap.enabled	boolean	true	Enable sitemap routes and the sitemap index link in robots.txt
seo.robotstxt.enabled	boolean	true	Enable /robots.txt route

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Canonical URL

The canonical URL is built from the node's URI plus the site's base URL. Query parameters from the current request are appended selectively based on the whitelist below.

Key	Type	Default	Description
seo.canonical.queryParameters	list of strings	["page"]	Query parameters to include in the canonical URL

Special behaviour for page: only appended when page > 1 — /blog?page=1 canonicalises to /blog.

Example:

[seo.canonical]
enabled = true
queryParameters = ["page", "tag", "category"]

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Robots Meta Tag

The robots meta tag is emitted only when at least one rule applies. Possible values are noindex,nofollow (node-level opt-out) and noindex,follow (query-parameter-driven).

Per-node frontmatter

Key	Type	Default	Description
seo.index	boolean	true	Set to false to emit noindex,nofollow for this node
seo.follow	boolean	true	Controls the follow/nofollow part when seo.index is false

Query-parameter rules (site properties)

Key	Type	Default	Description
seo.query.noindexParameters	list of strings	[]	Parameters that always trigger noindex,follow, regardless of count (e.g. sort, limit)
seo.query.contentParameters	list of strings	["page"]	Parameters that represent indexable content (e.g. tag, category)
seo.query.maxIndexableContentParameters	integer	-1 (disabled)	Maximum number of active content parameters before noindex,follow is triggered

Evaluation order:

1. seo.index: false on the node → noindex,nofollow (stops further evaluation)
2. Any active noindexParameters present in the request → noindex,follow
3. Active content parameters (excluding page and noindexParameters) exceed maxIndexableContentParameters → noindex,follow
4. Otherwise: no robots tag is emitted (browser default: index,follow)

Example — single curated filter indexable, navigation params always noindex:

[seo.canonical]
enabled = true
queryParameters = ["page", "tag", "category", "sort"]

[seo.query]
noindexParameters = ["sort", "limit"]
contentParameters = ["tag", "category"]
maxIndexableContentParameters = 1

URL	Canonical	Robots tag
/blog	/blog	—
/blog?page=2	/blog?page=2	—
/blog?tag=java	/blog?tag=java	—
/blog?tag=java&page=3	/blog?tag=java&page=3	—
/blog?sort=price	/blog?sort=price	noindex,follow
/blog?tag=java&category=cms	/blog?tag=java&category=cms	noindex,follow
/blog?tag=java&utm_source=nl	/blog?tag=java	—

---

Open Graph

Key	Scope	Description
seo.og.type	site properties	Default OG type (fallback: website)
seo.title	node frontmatter	Shared title for OG and Twitter
seo.description	node frontmatter	Shared description
seo.image	node frontmatter	Shared image URL
seo.url	node frontmatter	Shared URL override
seo.og.type	node frontmatter	Per-node OG type override
seo.og.url	node frontmatter	Per-node OG URL override
seo.og.title	node frontmatter	Per-node OG title override
seo.og.description	node frontmatter	Per-node OG description override
seo.og.image	node frontmatter	Per-node OG image override

---

Twitter Cards

Key	Scope	Description
seo.twitter.card	site properties	Default card type (fallback: summary)
seo.twitter.site	site properties	Twitter @username of the site
seo.twitter.creator	site properties	Twitter @username of the content creator
seo.twitter.card	node frontmatter	Per-node card type override
seo.twitter.url	node frontmatter	Per-node URL override
seo.twitter.title	node frontmatter	Per-node title override
seo.twitter.description	node frontmatter	Per-node description override
seo.twitter.image	node frontmatter	Per-node image override
seo.twitter.site	node frontmatter	Per-node site handle override
seo.twitter.creator	node frontmatter	Per-node creator handle override

---

Sitemap

/sitemap.xml is a sitemap index. It links /sitemap-nodes.xml and one /sitemap-collection-{name}.xml for each collection with a configured detail page in config/collections.yaml.

/sitemap-nodes.xml contains normal content nodes where seo.index is not false. Each entry has <loc> and <lastmod>.

Collection sitemaps contain items where seo.index is not false. URLs follow the collection's configured detail route, including date formats and mappings. Items whose required route fields are missing or invalid are skipped. Collection entries have <loc>; the collection API does not expose a modification date for them.

---

robots.txt

The robots.txt at /robots.txt is generated dynamically. When seo.sitemap.enabled is enabled, a Sitemap: directive pointing to /sitemap.xml is appended automatically.

Additional rules can be injected via the hook module/seo/robotstxt. The hook receives a RobotsTxt object and returns the modified version.

Hook example:

Javascript sample

$hooks.registerFilter("module/seo/robotstxt", (robots) -> {
    robots.group("*").disallow("/admin");
    robots.group("Googlebot").allow("/");
    return robots;
});

Sample for java

@Filter("module/seo/robotstxt")
public void extendRobotsTxt(RobotsTxt robots) {
    robots.group("*").disallow("/admin");
    robots.group("Googlebot").allow("/");
    return robots;
});

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Build

mvn clean package

Requires Java 25 and CondationCMS API 8.4.0.

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License

GPL v3 — see LICENSE.