🤯 CONSTRUCT query specification

contracts/okp4-cognitarium/src/contract.rs

@@ -80,7 +80,12 @@ pub fn query(deps: Deps<'_>, _env: Env, msg: QueryMsg) -> StdResult<Binary> {
         QueryMsg::Describe { query, format } => to_binary(&query::describe(
             deps,
             query,
-            format.unwrap_or(DataFormat::Turtle),
+            format.unwrap_or(DataFormat::default()),
+        )?),
+        QueryMsg::Construct { query, format } => to_binary(&query::construct(
+            deps,
+            query,
+            format.unwrap_or(DataFormat::default()),
         )?),
     }
 }
@@ -90,9 +95,9 @@ pub mod query {
 
     use super::*;
     use crate::msg::{
-        DescribeQuery, DescribeResponse, Node, Prefix, SelectItem, SelectQuery, SelectResponse,
-        SimpleWhereCondition, StoreResponse, TriplePattern, Value, VarOrNamedNode, VarOrNode,
-        VarOrNodeOrLiteral, WhereCondition,
+        ConstructQuery, DescribeQuery, DescribeResponse, Node, Prefix, SelectItem, SelectQuery,
+        SelectResponse, SimpleWhereCondition, StoreResponse, TriplePattern, Value, VarOrNamedNode,
+        VarOrNode, VarOrNodeOrLiteral, WhereCondition,
     };
     use crate::querier::{PlanBuilder, QueryEngine};
     use crate::rdf::{self, Atom, TripleWriter};
@@ -224,6 +229,14 @@ pub mod query {
             data: Binary::from(out),
         })
     }
+
+    pub fn construct(
+        _deps: Deps<'_>,
+        _query: ConstructQuery,
+        _format: DataFormat,
+    ) -> StdResult<SelectResponse> {
+        Err(StdError::generic_err("Not implemented"))
+    }
 }
 
 #[cfg(test)]
@@ -232,12 +245,13 @@ mod tests {
     use crate::error::StoreError;
     use crate::msg::ExecuteMsg::InsertData;
     use crate::msg::Node::NamedNode;
+    use crate::msg::QueryMsg::Construct;
     use crate::msg::SimpleWhereCondition::TriplePattern;
     use crate::msg::IRI::{Full, Prefixed};
     use crate::msg::{
-        DescribeQuery, DescribeResponse, Head, Literal, Prefix, Results, SelectItem, SelectQuery,
-        SelectResponse, StoreLimitsInput, StoreLimitsInputBuilder, StoreResponse, Value,
-        VarOrNamedNode, VarOrNode, VarOrNodeOrLiteral, WhereCondition,
+        ConstructQuery, DescribeQuery, DescribeResponse, Head, Literal, Prefix, Results,
+        SelectItem, SelectQuery, SelectResponse, StoreLimitsInput, StoreLimitsInputBuilder,
+        StoreResponse, Value, VarOrNamedNode, VarOrNode, VarOrNodeOrLiteral, WhereCondition,
     };
     use crate::state::{
         namespaces, triples, Namespace, Node, Object, StoreLimits, StoreStat, Subject, Triple,
@@ -1354,4 +1368,67 @@ mod tests {
             );
         }
     }
+
+    #[test]
+    fn proper_construct() {
+        let id = "https://ontology.okp4.space/dataverse/dataspace/metadata/dcf48417-01c5-4b43-9bc7-49e54c028473";
+        let cases = vec![(
+            ConstructQuery {
+                prefixes: vec![],
+                construct: vec![msg::TriplePattern {
+                    subject: VarOrNode::Node(NamedNode(Full(id.to_string()))),
+                    predicate: VarOrNode::Variable("p".to_string()),
+                    object: VarOrNodeOrLiteral::Variable("o".to_string()),
+                }],
+                r#where: vec![WhereCondition::Simple(TriplePattern(msg::TriplePattern {
+                    subject: VarOrNode::Node(NamedNode(Full(id.to_string()))),
+                    predicate: VarOrNode::Node(NamedNode(Full(
+                        "https://ontology.okp4.space/core/hasTopic".to_string(),
+                    ))),
+                    object: VarOrNodeOrLiteral::Node(NamedNode(Full(
+                        "https://ontology.okp4.space/thesaurus/topic/Test".to_string(),
+                    ))),
+                }))],
+            },
+            0,
+        )];
+
+        for case in cases {
+            let mut deps = mock_dependencies();
+
+            let info = mock_info("owner", &[]);
+            instantiate(
+                deps.as_mut(),
+                mock_env(),
+                info.clone(),
+                InstantiateMsg {
+                    limits: StoreLimitsInput::default(),
+                },
+            )
+            .unwrap();
+
+            execute(
+                deps.as_mut(),
+                mock_env(),
+                info.clone(),
+                InsertData {
+                    format: Some(DataFormat::RDFXml),
+                    data: read_test_data("sample.rdf.xml"),
+                },
+            )
+            .unwrap();
+
+            let res = query(
+                deps.as_ref(),
+                mock_env(),
+                Construct {
+                    query: case.0,
+                    format: Some(DataFormat::default()),
+                },
+            );
+
+            assert!(res.is_err());
+            assert_eq!(res.err().unwrap(), StdError::generic_err("Not implemented"));
+        }
+    }
 }

contracts/okp4-cognitarium/src/msg.rs

@@ -107,12 +107,26 @@ pub enum QueryMsg {
         /// If not provided, the default format is [Turtle](https://www.w3.org/TR/turtle/) format.
         format: Option<DataFormat>,
     },
+
+    /// # Construct
+    ///
+    /// Returns the resources matching the criteria defined by the provided query as a set of RDF
+    /// triples serialized in the provided format.
+    #[returns(ConstructResponse)]
+    Construct {
+        /// The query to execute.
+        query: ConstructQuery,
+        /// The format in which the triples are serialized.
+        /// If not provided, the default format is [Turtle](https://www.w3.org/TR/turtle/) format.
+        format: Option<DataFormat>,
+    },
 }
 
 /// # DataFormat
 /// Represents the format in which the data are serialized, for example when returned by a query or
 /// when inserted in the store.
 #[cw_serde]
+#[derive(Default)]
 pub enum DataFormat {
     /// # RDF XML
     /// Output in [RDF/XML](https://www.w3.org/TR/rdf-syntax-grammar/) format.
@@ -121,6 +135,7 @@ pub enum DataFormat {
     /// # Turtle
     /// Output in [Turtle](https://www.w3.org/TR/turtle/) format.
     #[serde(rename = "turtle")]
+    #[default]
     Turtle,
     /// # N-Triples
     /// Output in [N-Triples](https://www.w3.org/TR/n-triples/) format.
@@ -308,6 +323,16 @@ pub struct DescribeResponse {
     pub data: Binary,
 }
 
+/// # ConstructResponse
+/// Represents the response of a [QueryMsg::Construct] query.
+#[cw_serde]
+pub struct ConstructResponse {
+    /// The format of the data.
+    pub format: DataFormat,
+    /// The data serialized in the specified format.
+    pub data: Binary,
+}
+
 /// # Head
 /// Represents the head of a [SelectResponse].
 #[cw_serde]
@@ -389,6 +414,21 @@ pub struct DescribeQuery {
     pub r#where: WhereClause,
 }
 
+/// # ConstructQuery
+/// Represents a CONSTRUCT query over the triple store, allowing to retrieve a set of triples
+/// serialized in a specific format.
+#[cw_serde]
+pub struct ConstructQuery {
+    /// The prefixes used in the query.
+    pub prefixes: Vec<Prefix>,
+    /// The triples to construct.
+    /// If nothing is provided, the patterns from the `where` clause are used for construction.
+    pub construct: Vec<TriplePattern>,
+    /// The WHERE clause.
+    /// This clause is used to specify the triples to construct using variable bindings.
+    pub r#where: WhereClause,
+}
+
 /// # Prefix
 /// Represents a prefix in a [SelectQuery]. A prefix is a shortcut for a namespace used in the query.
 #[cw_serde]

docs/okp4-cognitarium.md

@@ -83,8 +83,27 @@ Returns a description of the resource identified by the provided IRI as a set of
 |`describe.format`|**[DataFormat](#dataformat)\|null**. The format in which the triples are serialized. If not provided, the default format is [Turtle](https://www.w3.org/TR/turtle/) format.|
 |`describe.query`|*(Required.) * **[DescribeQuery](#describequery)**. The query to execute.|
 
+### QueryMsg::Construct
+
+Returns the resources matching the criteria defined by the provided query as a set of RDF triples serialized in the provided format.
+
+|parameter|description|
+|----------|-----------|
+|`construct`|*(Required.) * **object**. |
+|`construct.format`|**[DataFormat](#dataformat)\|null**. The format in which the triples are serialized. If not provided, the default format is [Turtle](https://www.w3.org/TR/turtle/) format.|
+|`construct.query`|*(Required.) * **[ConstructQuery](#constructquery)**. The query to execute.|
+
 ## Responses
 
+### construct
+
+Represents the response of a [QueryMsg::Construct] query.
+
+|property|description|
+|----------|-----------|
+|`data`|*(Required.) * **[Binary](#binary)**. The data serialized in the specified format.|
+|`format`|*(Required.) * **[DataFormat](#dataformat)**. The format of the data.|
+
 ### describe
 
 Represents the response of a [QueryMsg::Describe] query.
@@ -143,6 +162,16 @@ An RDF [blank node](https://www.w3.org/TR/rdf11-concepts/#dfn-blank-node).
 |----------|-----------|
 |`blank_node`|*(Required.) * **string**. |
 
+### ConstructQuery
+
+Represents a CONSTRUCT query over the triple store, allowing to retrieve a set of triples serialized in a specific format.
+
+|property|description|
+|----------|-----------|
+|`construct`|*(Required.) * **Array<[TriplePattern](#triplepattern)>**. The triples to construct. If nothing is provided, the patterns from the `where` clause are used for construction.|
+|`prefixes`|*(Required.) * **Array<[Prefix](#prefix)>**. The prefixes used in the query.|
+|`where`|*(Required.) * **Array<[WhereCondition](#wherecondition)>**. The WHERE clause. This clause is used to specify the triples to construct using variable bindings.|
+
 ### DataFormat
 
 Represents the format in which the data are serialized, for example when returned by a query or when inserted in the store.