Search block¶

Repository & issue tracker

Repository: https://github.com/ragcon-ai/moodle-block_ragflowsearch
Issues / bug tracker: https://github.com/ragcon-ai/moodle-block_ragflowsearch/issues

Component: block_ragflowsearch · Release: 0.3.2 · Requires: Moodle 5.0–5.2 · Depends on: aiprovider_ragflow

A Moodle block that adds a search box to any page and searches one or more RAGflow knowledge bases semantically, listing the matching source documents. It is retrieval only — no LLM (fast, cheap, no hallucination, links to real documents). The search widget itself is hosted by the shared AI provider; the block chooses the knowledge base and scope per instance.

Features¶

Placeable on any page (courses, the Dashboard, the front page, …).
Semantic search over one or more RAGflow datasets, chosen per block instance.
Ranked results with a relevance score and snippet, each linking to the source document through the provider's secure download proxy (the RAGflow API key never reaches the browser).
Fewer, better matches — a relevance floor, a relevance "cliff" and a result cap trim weak hits; images/media get their own group so they aren't lost; an optional rerank model sharpens precision further (see Result quality).
Scope: whole KB or current course (course scope filters by a configurable metadata field; on pages without a course the whole KB is searched).
Login-gated (no content for logged-out users or guests); one instance per page.
Helpful empty states: a not configured hint for users who can add the block, and a no knowledge bases available message if the provider isn't enabled.

Configuration¶

There is no site-wide settings page — all configuration is per block instance, and only site administrators may set it (non-admins see an "only site administrators can choose the knowledge base" message, and their saves cannot clear the choice).

Per-instance block config (Configure this RAGflow search block)¶

Setting	Type	Default	Meaning
Knowledge base(s) (`config_datasets`)	autocomplete (multiple)	none (required)	The RAGflow dataset(s) this block searches. Select one or more; the block does not search until at least one is chosen.
Search scope (`config_scope`)	select	`Whole knowledge base`	Whole knowledge base or Current course only (matched via the course metadata field). On pages without a course, the whole KB is searched.
Course metadata field (`config_coursefield`)	text	`course_id`	RAGflow document metadata field holding the Moodle course id. Only used when scope is Current course only.
Rerank model (`config_rerankmodel`)	text	empty (off)	Optional. A RAGflow rerank model id (e.g. a bge-reranker configured in your RAGflow). When set, RAGflow reorders the candidates with a cross-encoder for markedly better precision. Empty = plain vector/keyword ranking.

Result quality (fewer, better matches)¶

The search is tuned to return a short, relevant list instead of a fixed number of hits. This needs no configuration — the defaults are sensible; only the optional rerank model is a setting.

Relevance floor — matches below a minimum score are dropped, so weakly related documents no longer clutter the list.
Relevance "cliff" + result cap — once the scores fall away from the best hit (or the cap of 5 is reached) the list stops. A query with two strong matches returns two, not a padded eight.
Images & media handled separately — images (and other media) embed with low text similarity, so a single floor would wrongly hide them. They get a lower floor and appear in their own "Images & media" group below the text results, rather than being dropped or diluting the text ranking.
Optional reranking — set a rerank model (above) and RAGflow reorders the retrieved candidates with a cross-encoder. This is the single biggest precision gain: the truly relevant documents rise to the top and the tail is cut by the cliff. It is opt-in (needs a rerank model in your RAGflow) and adds a little latency.

Benefits: shorter, more trustworthy result lists; no irrelevant filler; images stay findable; and, with reranking on, noticeably sharper ordering — all with sensible defaults out of the box.

Capabilities¶

Capability	Default roles	Purpose
`block/ragflowsearch:addinstance`	Teacher, Manager	Add a search block to a page
`block/ragflowsearch:myaddinstance`	Authenticated user	Add the block to the Dashboard / My home

Note

Choosing the knowledge base and scope is restricted to site administrators (not a capability), because a dataset is a site-wide resource.

Privacy¶

The block stores no personal data. Search queries are sent to the configured RAGflow service by the AI provider to retrieve matching documents; source links go through the provider's secure proxy.

Note: This documentation was created with the help of AI. Spotted an error, an omission, or something unclear? Please report it in the ragcon-docs GitHub repository so we can fix it.