XWiki Platform

XWiki Platform is a fully‑featured, open‑source wiki engine that doubles as an application runtime. It exposes a rich Java‑based API, a modular plugin system, and a powerful rendering engine that supports multiple markup formats. From a developer’s standpoint, XWiki is not just a content management system; it is an extensible framework that can host custom business applications, dashboards, or micro‑services on top of its core.

Key Features

• Java EE / OSGi Core – The platform runs on a servlet container (e.g., Tomcat, Jetty) and is built around the OSGi module system. This allows fine‑grained dependency management, hot deployment of bundles, and a clean separation between core services and extensions.
• Structured Data & RDF – Every page is stored as a Document object that can be queried with XWiki’s own query language or the standard JPA/Hibernate API. The data model is relational but can be exposed as RDF/SPARQL endpoints for semantic applications.
• REST & SOAP APIs – XWiki ships with a comprehensive REST API (/xwiki/rest) that exposes CRUD operations for pages, attachments, users, and custom extensions. SOAP services are also available for legacy integrations.
• Scripting & Automation – The platform supports Groovy, JavaScript (via Nashorn/Node), and Velocity templates. Developers can write scripts that run on the server or as scheduled jobs, enabling complex workflows without leaving Java.

Technical Stack

The OSGi foundation gives developers the ability to replace or extend any component at runtime, while the Gradle build system ensures reproducible artifacts and continuous integration.

Core Capabilities & APIs

• Extensible Plugin Architecture – Plugins are OSGi bundles that can register services, UI components, or REST endpoints. The org.xwiki.component.annotation API makes it trivial to inject dependencies.
• Event Bus & Listeners – The platform publishes events (e.g., DocumentCreatedEvent) that can be consumed by custom listeners. This is ideal for audit trails, notifications, or integration with external systems.
• Security Model – Fine‑grained ACLs per page, role‑based authentication (LDAP, SAML, OAuth2), and a pluggable security provider interface.
• Multitenancy & Namespaces – XWiki can host multiple spaces (namespaces) with isolated data stores, enabling SaaS‑style deployments.

Deployment & Infrastructure

XWiki is lightweight enough to run on a single node yet designed for horizontal scaling. Standard deployment involves:

• Servlet Container – Deploy the xwiki.war to Tomcat/Jetty. For production, a reverse proxy (NGINX) is recommended.
• Database – A single RDBMS instance suffices; for high availability, read replicas or sharding can be configured.
• Containerization – Official Docker images expose environment variables for database connection, cache settings, and OSGi bundle configuration. Kubernetes operators simplify scaling and rolling upgrades.
• Monitoring – Prometheus metrics are exposed via the /metrics endpoint; health checks are available through /xwiki/rest/health.

Integration & Extensibility

• REST/Webhooks – Custom webhooks can be registered on events, allowing integration with CI/CD pipelines or external monitoring tools.
• External Authentication – LDAP/SAML/OAuth2 providers are plug‑inable; custom authentication handlers can be written in Java.
• GraphQL Layer – Experimental GraphQL support lets developers query the XWiki data model with a single endpoint.
• UI Customization – The Velocity/FreeMarker templates can be overridden, and modern React or Vue components can be embedded via the XWiki Web UI APIs.

Developer Experience

• Documentation – Comprehensive guides (Developer, Administrator, User) are hosted on the official site. API reference is auto‑generated from Javadoc.
• Community & Support – A vibrant mailing list, chat (Mattermost), and a Jira issue tracker provide quick assistance. The project’s contribution flow is well‑documented, with continuous integration ensuring code quality.
• Testing – The platform ships with a full test harness, including functional tests that spin up an in‑memory database and headless browser for UI regression.

Use Cases

• Enterprise Knowledge Base – Leverage structured data and ACLs to build a secure, searchable knowledge hub.
• Custom Business Apps – Create forms, dashboards, and workflow engines that run natively inside XWiki.
• SaaS Multi‑Tenant Platform – Use namespaces and OSGi to host isolated instances for different customers.
• Data‑Driven Analytics – Expose page metadata as RDF/SPARQL and integrate with BI tools.

Advantages Over Alternatives

• Full Java Ecosystem – No need to mix languages; all extensions can be written in Java or Groovy.