1 files changed, 3 insertions, 3 deletions

diff --git a/lib/format.php b/lib/format.php
index 72cf531..25748f0 100644
--- a/lib/format.php
+++ b/lib/format.php
@@ -12,15 +12,15 @@ function export_as_requested($content) {
     $content["tsv"]=$content["All"];
     unset($content["All"]);
   }
-  if (isset($content["json"]) && isset($_GET["json"])) {
+  if (isset($content["json"]) && array_key_exists("json", $_GET)) {
     header ("Content-type: application/json");
     print json_encode(
       $content["json"],
       JSON_UNESCAPED_SLASHES
     );
-  } elseif (isset($content["tsv"]) && isset($_GET["tsv"])) {
+  } elseif (isset($content["tsv"]) && array_key_exists("tsv", $_GET)) {
     header ("Content-type: text/tab-separated-values");
-    if (! isset($_GET["no-headers"]))
+    if (! array_key_exists("no-headers", $_GET))
       print implode("\t",array_keys($content["tsv"][0])) . "\n";
     print implode(
       "",