SHACL Validation Reference¶

This reference documents the shape layers used by the SHACL Validator, the constraint codes it emits, and the rationale for the RONL-specific shapes. The validator runs on the shared backend at POST /v1/shacl/validate (file-local) and POST /v1/shacl/validate-merged (merge-simulated), and is used by the Linked Data Explorer's standalone SHACL Validator view.

How to read this reference¶

Issues are grouped into three layers (the CPRMV 0.4.1 layer was added in v1.9.5). Each issue carries a severity, a typed code, the focus node and property path it applies to, and — for cardinality and uniqueness constraints — the offending values (no longer truncated as of v1.9.7).

Field	Meaning
Layer	`CPSV-AP 3.2.0` (canonical, vendored), `CPRMV 0.4.1` (CPRMV shapes), or `RONL Custom` (RONL-authored)
Code	Derived from the SHACL `sh:sourceConstraintComponent` local name (e.g. `SHACL-MAXCOUNT`)
Severity	`error` (`sh:Violation`), `warning` (`sh:Warning`), `info` (`sh:Info`)
Focus node	The subject the constraint was evaluated against
Path	The property the constraint applies to

Validation modes¶

Mode	Endpoint	Behaviour
File-local	`POST /v1/shacl/validate`	Validates the uploaded Turtle exactly as written.
Merge-simulated	`POST /v1/shacl/validate-merged`	Fetches the already-published triples for the file's subjects via a read-only SPARQL `CONSTRUCT`, unions them with the file, then validates. Catches collisions that only emerge once the file is added to the store.

Merge-simulated mode never writes to the endpoint.

Layer 1 — CPSV-AP 3.2.0¶

This layer is the canonical SHACL shapes file from the SEMIC CPSV-AP 3.2.0 release, vendored verbatim into packages/backend/shapes/cpsv-ap/3.2.0/cpsv-ap-SHACL.ttl. It contains 32 sh:NodeShape definitions (pure SHACL Core — no SPARQL constraints) targeting the full CPSV-AP model:

cpsv:PublicService, cpsv:Rule, m8g:PublicOrganisation, m8g:ContactPoint, m8g:Channel, m8g:Cost, m8g:Evidence, m8g:Requirement, m8g:Output, locn:Address, dcat:Dataset, foaf:Agent, org:Organization, skos:Concept, and related classes.

The constraints most relevant to RONL publishing:

Class	Constraint	Code
`cpsv:Rule`	`dct:identifier` is required (`sh:minCount 1`)	`SHACL-MINCOUNT`
`cpsv:Rule`	`dct:title` / `dct:description` must be `rdf:langString`	`SHACL-DATATYPE`
`m8g:PublicOrganisation`	`dct:spatial` is required (`sh:minCount 1`)	`SHACL-MINCOUNT`

Note

The CPSV-AP Rule shape constrains dct:title / dct:description only by datatype — it does not cap their cardinality. The single-value-per-language rule is supplied by the RONL Custom layer, so the two layers complement rather than duplicate each other.

Layer 2 — RONL Custom¶

RONL-authored shapes in packages/backend/shapes/ronl/, layered on top of CPSV-AP. They encode publishing invariants that are stricter than (or orthogonal to) the canonical profile, chosen specifically to prevent merge-time fan-out and subject-URI collisions in TriplyDB.

These shapes prefer sh:uniqueLang true over sh:maxCount 1 for human-readable labels, so a record carrying one @nl and one @en value passes, while two values sharing a language tag are flagged.

PublicOrganisationUniquenessShape¶

Target: m8g:PublicOrganisation

Path	Constraint	Code
`foaf:homepage`	`sh:maxCount 1`	`SHACL-MAXCOUNT`
`dct:identifier`	`sh:maxCount 1`	`SHACL-MAXCOUNT`
`cv:spatial`	`sh:maxCount 1`	`SHACL-MAXCOUNT`
`skos:prefLabel`	`sh:uniqueLang true`	`SHACL-UNIQUELANG`

Rationale. When two publications describe the same organisation with divergent single-valued properties (most commonly foaf:homepage), the union in TriplyDB produces multiple values on one subject, which fan out into duplicate rows in downstream queries. Capping these at one surfaces the divergence at validation time — especially in merge-simulated mode, where the conflicting value lives in the already-published graph rather than the uploaded file.

RuleUniquenessShape¶

Target: cpsv:Rule

Path	Constraint	Code
`dct:title`	`sh:uniqueLang true`	`SHACL-UNIQUELANG`
`dct:description`	`sh:uniqueLang true`	`SHACL-UNIQUELANG`

Rationale. Publishing several distinct rules under one subject URI is a common authoring error: the subject accumulates several same-language titles and descriptions. sh:uniqueLang detects this while still allowing a single rule to carry one title/description per language. The fix is to give each rule its own subject URI.

Layer 3 — CPRMV 0.4.1¶

Added in v1.9.5. The CPRMV SHACL shapes, vendored into packages/backend/shapes/cprmv/0.4.1/cprmv.shacl.ttl, validate the CPRMV rule-management model — cprmv:RuleSet, cprmv:Rule, and cprmv:RuleMethod and their required properties. This is the same shape set the CPRMV API and CPSV Editor validate against, so a file that passes here is conformant for the rule-management vocabulary independently of its CPSV-AP service metadata. A layer with no shape files present reports Not loaded rather than a green check.

Parameter and temporal-rule shapes (v1.9.8)¶

Two shapes were added to the CPRMV layer, extending validation beyond the ruleset model:

Shape	Target class	Constraints
`cprmv:ParameterWaardeShape`	`cprmv:ParameterWaarde`	Required: `skos:notation` [1,1] `xsd:string`, `skos:prefLabel` [1,n] `rdf:langString`. Optional: `schema:value` [0,1] `xsd:decimal`, `schema:unitCode` [0,1] `xsd:string`, `dct:description` [0,1] `rdf:langString`, `cprmv:validFrom`/`cprmv:validUntil` [0,1] `xsd:date`.
`cprmv:TemporalRuleShape`	`cprmv:TemporalRule`	All optional: `cprmv:validFrom` [0,1] `xsd:date`, `cprmv:validUntil` [0,1] `xsd:date`, `cprmv:confidenceLevel` [0,1] `xsd:string`, `cprmv:isBasedOn` [0,n] `sh:class cpsv:Rule`.

The change also adds the skos:, schema:, and dct: prefix declarations these shapes require; existing shapes are unchanged. The mandatory skos:notation/skos:prefLabel on ParameterWaarde is the same constraint the CPSV Editor enforces client-side (from its v1.10.4), so a parameter that passes in the editor also passes here.

Constraint codes¶

Codes are generic — any SHACL Core constraint component can appear, named SHACL-<COMPONENT>. The ones the RONL data exercises in practice:

SHACL-MINCOUNT¶


Severity	🔴 error
Trigger	A focus node has fewer values for a path than `sh:minCount` requires
Rationale	A required property is absent. For `cpsv:Rule` this is almost always a missing `dct:identifier`; for `m8g:PublicOrganisation` it can be a missing `dct:spatial`.
Fix	Add the missing property to the subject in your Turtle.

SHACL-MAXCOUNT¶


Severity	🔴 error
Trigger	A focus node has more values for a path than `sh:maxCount` permits
Rationale	A property that must be single-valued for RONL publishing has several values. In merge-simulated mode this usually means your value differs from the one already published.
Fix	Reconcile the values so only one remains — either in your file, or by correcting the published record.

SHACL-UNIQUELANG¶


Severity	🔴 error
Trigger	Two or more values of a path share the same language tag while `sh:uniqueLang true` is set
Rationale	Typically several `cpsv:Rule` blocks were published under one subject URI, so the subject carries multiple same-language titles/descriptions.
Fix	Give each rule its own subject URI so each carries at most one title and description per language.

Severity summary by component¶

Code	Layer(s)	Severity
`SHACL-MINCOUNT`	CPSV-AP 3.2.0	error
`SHACL-MAXCOUNT`	RONL Custom	error
`SHACL-UNIQUELANG`	RONL Custom, CPSV-AP 3.2.0	error
`SHACL-DATATYPE`	CPSV-AP 3.2.0	error

Known divergence — `dct:spatial` vs `cv:spatial`¶

The canonical CPSV-AP 3.2.0 PublicOrganisation shape requires dct:spatial (http://purl.org/dc/terms/spatial), while RONL data — and the RONL PublicOrganisationUniquenessShape — use cv:spatial (http://data.europa.eu/m8g/spatial). As a result the CPSV-AP layer reports a SHACL-MINCOUNT on dct:spatial for RONL organisations.

This is not a validator defect — it is the validator correctly surfacing a modelling difference between the RONL profile and the canonical profile. The decision on whether to align RONL to dct:spatial or accept the divergence is deferred to a dedicated data-modelling pass.

API contract¶

Both endpoints accept a JSON body and return the standard envelope.

Request:

{ "content": "<turtle>", "endpoint": "https://…/sparql" }

endpoint applies to validate-merged only and is optional (the configured default is used when omitted).

Response:

{
  "success": true,
  "data": {
    "valid": false,
    "parseError": null,
    "layers": {
      "cpsv-ap":     { "label": "CPSV-AP 3.2.0", "loaded": true, "issues": [ ... ] },
      "cprmv":       { "label": "CPRMV 0.4.1",   "loaded": true, "issues": [ ... ] },
      "ronl-custom": { "label": "RONL Custom",   "loaded": true, "issues": [ ... ] }
    },
    "summary": { "errors": 2, "warnings": 0, "infos": 0 }
  },
  "timestamp": "2026-06-05T00:00:00.000Z"
}

Each issue has the shape { severity, code, message, location? }, where location is the focus node and property path. A layer with loaded: false had no shape files present and was not evaluated.