View merge rules

When a search request contains a viewId, the Infocenter loads the view and uses it as the base configuration. The properties of the request are then merged into the view. The general rule is:

• Filters of the view always apply. Filters of the request are added on top with a logical AND, so a request can only refine the result of the view, never expand it.
• Settings such as orderBy, select, resultsPerPage or currentPage that are set in the request replace the value of the view.
• Facets are merged according to the rules below.

Facets merge rules

Both the view and the request can define facets. The following table shows which facets the response contains for every combination. null means the property is not provided, empty means an empty list [], value means a list with at least one facet.

Facets in the view	Facets in the request	Facets in the response	Explanation
null	null	null	Neither side defines facets: the search API returns its default behavior.
null	empty	empty	The request explicitly asks for no facets.
empty	null	empty	The view explicitly defines no facets. A request without facets cannot be distinguished from a request that does not provide them, so the view wins.
null	value	value	Only the request defines facets: they are used as they are.
empty	value	value	The view defines no facets, the request does: the facets of the request are used.
value	null	value	Only the view defines facets: they are used as they are. This is the usual case for a website that uses a view.
value	empty	empty	The request explicitly asks for no facets and overrides the view.
value	value	intersection	Both define facets: only the facets whose name exists on both sides are returned, with the definition of the request. A request cannot add facets that the view does not define.

Example

A view defines the facets categoryTree and containedInPlace/id. A website sends a search with the viewId and the facets categoryTree and tag.

The response contains only categoryTree: it is the only facet that exists in both the view and the request. tag is not part of the view and containedInPlace/id was not requested.

If the website sends the search with the viewId and no facets property, the response contains both facets of the view, categoryTree and containedInPlace/id.

flowchart LR
    subgraph V["View"]
        direction TB
        V1["categoryTree"]
        V2["containedInPlace/id"]
    end
    subgraph R["Request with viewId"]
        direction TB
        R1["categoryTree"]
        R2["tag"]
    end
    M{"Merge<br/>keep names on both sides"}
    subgraph O["Response"]
        O1["categoryTree"]
    end
    subgraph D["Not returned"]
        direction TB
        D2["containedInPlace/id<br/>not requested"]
        D3["tag<br/>not defined in the view"]
    end
    V --> M
    R --> M
    M -->|"on both sides"| O
    M -.->|"on one side only"| D
    classDef cat fill:#d8f3dc,stroke:#2d6a4f,color:#1b4332
    classDef place fill:#ffe8cc,stroke:#d9480f,color:#862e0a
    classDef tag fill:#dbe4ff,stroke:#3b5bdb,color:#1e3a8a
    classDef kept fill:#b7e4c7,stroke:#1b4332,color:#1b4332,font-weight:bold,stroke-width:2px
    class V1,R1 cat
    class V2,D2 place
    class R2,D3 tag
    class O1 kept