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  • VOS.VirtCustomizeSPARQLEndpoint(Last) -- DAVWikiAdmin? , 2017-06-13 05:48:02 Edit WebDAV System Administrator 2017-06-13 01:48:02

    Customizing the Virtuoso SPARQL Endpoint

    This page will guide you through changing the SPARQL endpoint web page. You can create different variants of the page for different IRIs:

    1. The default SPARQL endpoint page is found in the procedure named WS.WS."/!sparql/", which is built from source code found in libsrc/Wi/sparql_io.sql.
    2. Copy the code from the above procedure, and load it to a different name, e.g., WS.WS."/!sparql_new/", through iSQL --

      SQL> CREATE PROCEDURE WS.WS."/!sparql_new/" ( INOUT path VARCHAR, INOUT params ANY, INOUT lines ANY ) {... http(' <p>TEST This query page is designed to help you test OpenLink Virtuoso</p> ... }; Done. -- 60 msec. SQL>

    3. Remove the VHost definition targeting the original page --

      SQL> DB.DBA.VHOST_REMOVE (lpath=>'/sparql');

    4. Add a VHost definition targeting your new page. The command follows this form --

      SQL> DB.DBA.VHOST_DEFINE ( lpath=>'/sparql/', ppath => '/your-function-name/', is_dav => 1, vsp_user => 'dba', opts => vector('noinherit', 1) );

      -- so, for this example --

      SQL> DB.DBA.VHOST_DEFINE ( lpath=>'/sparql/', ppath => '/!sparql_new/', is_dav => 1, vsp_user => 'dba', opts => vector('noinherit', 1) );

    5. Give the SPARQL user permission to execute your new page, following this form --

      SQL> GRANT EXECUTE ON WS.WS."your-function" TO "SPARQL" ;

      -- so, for this example --

      SQL> GRANT EXECUTE ON WS.WS."/!sparql_new/" TO "SPARQL" ;

      Note: you should use double quotes around name of "SPARQL" user and the upper case, to avoid confusion with the SPARQL keyword, you should always use double-quote wrappers and upper-case to refer to the "SPARQL" user.

    6. Set attributes on your new page, such that Virtuoso's HTTP server component will not treat it as a physical path (DAV or filesystem) to be read and compiled as a procedure, following the command form --

      SQL> registry_set ( '/your-function-name/', 'no_vsp_recompile' );

      -- so, for this example --

      SQL> registry_set ( '/!sparql_new/', 'no_vsp_recompile' );

    7. Access the new SPARQL endpoint, which should show your changes --



    CategorySPARQL CategoryVirtuoso