diff -r 1f9853178fcd -r 366509ae2f37 server/src/app/Http/Controllers/Api/ThemeController.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/server/src/app/Http/Controllers/Api/ThemeController.php	Sat May 07 10:06:26 2016 +0200
@@ -0,0 +1,113 @@
+<?php
+
+namespace CorpusParole\Http\Controllers\Api;
+
+// use Illuminate\Http\Request;
+// use CorpusParole\Http\Requests;
+use CorpusParole\Http\Controllers\Controller;
+
+use Illuminate\Http\Request;
+use EasyRdf\Resource;
+use EasyRdf\Literal;
+
+use CorpusParole\Libraries\Sparql\SparqlClient;
+use CorpusParole\Services\LexvoResolverInterface;
+use CorpusParole\Services\BnfResolverInterface;
+
+
+class ThemeController extends Controller
+{
+    private $sparqlClient = null;
+
+    public function __construct(SparqlClient $sparqlClient, LexvoResolverInterface $lexvoResolver, BnfResolverInterface $bnfResolver) {
+        $this->sparqlClient = $sparqlClient;
+        $this->lexvoResolver = $lexvoResolver;
+        $this->bnfResolver = $bnfResolver;
+    }
+
+    /**
+     * Display the specified resource.
+     *
+     * @return \Illuminate\Http\Response
+     */
+    public function index(Request $request)
+    {
+        $filter = $request->input('filter', 'bnf');
+        $resolve = filter_var($request->input('resolve', true), FILTER_VALIDATE_BOOLEAN);
+
+        $filterClause = "";
+
+        if($filter === 'bnf') {
+            $filterClause = "FILTER (isIRI(?o) && regex(str(?o), '^".config('corpusparole.bnf_ark_base_url')."')) .";
+        }
+        elseif($filter === 'uri') {
+            $filterClause = "FILTER isIRI(?o) .";
+        }
+        elseif($filter === 'all' || $filter === 'none' || $filter === '') {
+            $filterClause = "";
+        }
+        else {
+            abort(401,"Value for filter parameter must be in 'bnf', 'uri', 'all' or 'none'");
+        }
+
+        $query =  preg_replace('/\s+/', ' ',
+         "select (?o as ?theme) (COUNT(?s) as ?count) where {
+            ?s a <http://www.europeana.eu/schemas/edm/ProvidedCHO> .
+            ?s <http://purl.org/dc/elements/1.1/subject> ?o .
+            $filterClause
+          }
+          GROUP BY ?o
+          ORDER BY DESC(?count)");
+
+        $docs = $this->sparqlClient->query($query);
+
+        $themes = [];
+        $labels = [];
+
+        $bnfUris = [];
+        $lexvoUris = [];
+
+        foreach ($docs as $row) {
+            $key = "";
+            $label = null;
+            if($row->theme instanceof Resource) {
+                $key = $row->theme->getUri();
+                if($resolve && strpos($key, config('corpusparole.bnf_ark_base_url')) === 0) {
+                    array_push($bnfUris, $key);
+                }
+                elseif($resolve && strpos($key, config('corpusparole.lexvo_base_url')) === 0) {
+                    array_push($lexvoUris, $key);
+                }
+                $label = null;
+            }
+            elseif($row->theme instanceof Literal) {
+                $key = $row->theme->getValue();
+                $label = $row->theme->getValue();
+            }
+
+            $themes[$key] = [
+                "label" => $label,
+                "count" => $row->count->getValue()
+            ];
+        }
+
+        if($resolve) {
+            if(count($lexvoUris) > 0) {
+                $labels = $this->lexvoResolver->getNames($lexvoUris);
+            }
+            if(count($bnfUris) > 0) {
+                $labels = array_merge($labels, $this->bnfResolver->getLabels($bnfUris));
+            }
+            foreach ($themes as $themeKey => $themeDef) {
+                if(array_key_exists($themeKey, $labels)) {
+                    $themeDef['label'] = $labels[$themeKey];
+                }
+                $themes[$themeKey] = $themeDef;
+            }
+        }
+
+        return response()->json(['themes' => $themes ]);
+
+    }
+
+}