Feature: BlankNode::make_uuid (#444)

Author: nkaralis

src/rdf4cpp/BlankNode.cpp

@@ -7,6 +7,10 @@
 
 #include <cstring>
 
+#include <boost/uuid/random_generator.hpp>
+#include <boost/uuid/uuid.hpp>
+#include <boost/uuid/uuid_io.hpp>
+
 namespace rdf4cpp {
 
 namespace detail_bnode_inlining {
@@ -64,6 +68,12 @@ BlankNode BlankNode::make(std::string_view identifier, storage::DynNodeStoragePt
     return BlankNode{identifier, node_storage};
 }
 
+BlankNode BlankNode::make_uuid(storage::DynNodeStoragePtr node_storage) {
+    boost::uuids::random_generator_mt19937 gen{};
+    boost::uuids::uuid const u = gen();
+    return BlankNode{boost::uuids::to_string(u), node_storage};
+}
+
 BlankNode BlankNode::make_unchecked(std::string_view identifier, storage::DynNodeStoragePtr node_storage) {
     auto const id = [&]() {
         if (auto const inlined = detail_bnode_inlining::try_into_inlined(identifier); !inlined.null()) {

src/rdf4cpp/BlankNode.hpp

@@ -30,6 +30,13 @@ struct BlankNode : Node {
      */
     [[nodiscard]] static BlankNode make(std::string_view identifier, storage::DynNodeStoragePtr node_storage = storage::default_node_storage);
 
+    /**
+     * creates a new BlankNode from a random UUID (Universally Unique IDentifier)
+     * @return UUID IRI
+     */
+    [[nodiscard]] static BlankNode make_uuid(storage::DynNodeStoragePtr node_storage = storage::default_node_storage);
+
+
     /**
      * Constructs a bnode from an identifier
      */

tests/nodes/tests_Node.cpp

@@ -225,6 +225,14 @@ TEST_CASE("IRI UUID") {
     CHECK(regex::Regex{"^urn:uuid:[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$"}.regex_match(uuid.identifier()));
 }
 
+TEST_CASE("BNODE UUID") {
+    BlankNode uuid = BlankNode::make_uuid();
+    BlankNode uuid2 = BlankNode::make_uuid();
+
+    CHECK(uuid != uuid2);  // note: non-deterministic but should basically never fail
+    CHECK(regex::Regex{"[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$"}.regex_match(uuid.identifier()));
+}
+
 TEST_CASE("IRI fetch or serialize") {
     auto const x = IRI::make("https://example.com#some-iri");
     auto const expected = x.identifier();