Merge pull request #75 from zazuko:BenjaminHofstetter/issue74

fix issue 74

samples/issues.sparqlbook

@@ -0,0 +1,14 @@
+[
+  {
+    "kind": 1,
+    "language": "markdown",
+    "value": "# Using FROM clause yields 'Unknown query type' #74\n\n## Error\nSPARQL error: Unknown query type\n\n## Cause\nThe notebook tries to guess the query type in order to set the HTTP ACCEPT header. Because some stores return a SPO SPARQL JSON result for construct queries and we want turtle.\n\nThe notebook ignores comment and empty lines, so the first non-empty line should be a construct, select, ask, or describe.\n\nThis test is not enough. \n\n## Solution\n\nAt the moment we don't want to parse the query with SPARQLjs. To be store / sparql flavour agnostic. \n",
+    "metadata": {}
+  },
+  {
+    "kind": 2,
+    "language": "sparql",
+    "value": "PREFIX cube: <https://cube.link/>\nPREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>\n\nfrom <https://lindas.admin.ch/foen/cube>\nselect *\nWHERE  \n{ \n    BIND(<https://environment.ld.admin.ch/foen/ubd000502/1> AS ?cube)\n    ?cube  rdf:type  cube:Cube\n}\n",
+    "metadata": {}
+  }
+]

src/extension/endpoint/sparql-utils.ts

@@ -17,7 +17,20 @@ export function getSPARQLQueryKind(query: string): SPARQLQueryKind {
     const linesWithoutPrefix = linesWithoutCommentsAndEmpty.filter(line => {
         return !line.startsWith('prefix');
     });
-    const firstLine = linesWithoutPrefix[0];
+    const lineWithQueryKind = linesWithoutPrefix.filter(line => {
+        return line.startsWith(SPARQLQueryKind.select) ||
+            line.startsWith(SPARQLQueryKind.construct) ||
+            line.startsWith(SPARQLQueryKind.describe) ||
+            line.startsWith(SPARQLQueryKind.ask) ||
+            line.startsWith(SPARQLQueryKind.update) ||
+            line.startsWith(SPARQLQueryKind.load) ||
+            line.startsWith(SPARQLQueryKind.clear) ||
+            line.startsWith(SPARQLQueryKind.drop) ||
+            line.startsWith(SPARQLQueryKind.create) ||
+            line.startsWith(SPARQLQueryKind.json);
+    }
+    );
+    const firstLine = lineWithQueryKind[0];
     if (firstLine !== undefined) {
         if (firstLine.startsWith(SPARQLQueryKind.select)) {
             return SPARQLQueryKind.select;