GH-5330 throw an exception for unknown repo in getRepositoryCon (#5340)

Author: hmottestad

tools/server-spring/src/main/java/org/eclipse/rdf4j/http/server/repository/RepositoryInterceptor.java

@@ -133,8 +133,11 @@ public static Repository getRepository(HttpServletRequest request) {
 	 * @param request the {@link HttpServletRequest} for which a {@link RepositoryConnection} is to be returned
 	 * @return a configured {@link RepositoryConnection}
 	 */
-	public static RepositoryConnection getRepositoryConnection(HttpServletRequest request) {
+	public static RepositoryConnection getRepositoryConnection(HttpServletRequest request) throws ClientHTTPException {
 		Repository repo = getRepository(request);
+		if (repo == null) {
+			throw new ClientHTTPException(SC_NOT_FOUND, "Unknown repository: " + getRepositoryID(request));
+		}
 		RepositoryConnection conn = repo.getConnection();
 		conn.getParserConfig().addNonFatalError(BasicParserSettings.VERIFY_DATATYPE_VALUES);
 		conn.getParserConfig().addNonFatalError(BasicParserSettings.VERIFY_LANGUAGE_TAGS);

tools/server-spring/src/main/java/org/eclipse/rdf4j/http/server/repository/namespaces/NamespaceController.java

@@ -115,7 +115,7 @@ private ModelAndView getUpdateNamespaceResult(HttpServletRequest request, String
 	}
 
 	private ModelAndView getRemoveNamespaceResult(HttpServletRequest request, String prefix)
-			throws ServerHTTPException {
+			throws ServerHTTPException, ClientHTTPException {
 		try (RepositoryConnection repositoryCon = RepositoryInterceptor.getRepositoryConnection(request)) {
 			repositoryCon.removeNamespace(prefix);
 		} catch (RepositoryException e) {

tools/server-spring/src/main/java/org/eclipse/rdf4j/http/server/repository/namespaces/NamespacesController.java

@@ -117,7 +117,7 @@ private ModelAndView getExportNamespacesResult(HttpServletRequest request, HttpS
 	}
 
 	private ModelAndView getClearNamespacesResult(HttpServletRequest request, HttpServletResponse response)
-			throws ServerHTTPException {
+			throws ServerHTTPException, ClientHTTPException {
 		try (RepositoryConnection repositoryCon = RepositoryInterceptor.getRepositoryConnection(request)) {
 			try {
 				repositoryCon.clearNamespaces();