4 files changed, 8 insertions, 7 deletions
diff --git a/library/Graphite/Graphing/Chart.php b/library/Graphite/Graphing/Chart.php
index ded8ae8..bee5e7d 100644
--- a/library/Graphite/Graphing/Chart.php
+++ b/library/Graphite/Graphing/Chart.php
@@ -107,9 +107,9 @@ class Chart
         $response
             ->setHeader('Content-Type', 'image/png', true)
             ->setHeader('Content-Disposition', 'inline; filename="graph.png"', true)
-            ->setHeader('Cache-Control', null, true)
-            ->setHeader('Expires', null, true)
-            ->setHeader('Pragma', null, true)
+            ->setHeader('Cache-Control', '', true)
+            ->setHeader('Expires', '', true)
+            ->setHeader('Pragma', '', true)
             ->setBody($image)
             ->sendResponse();
 
diff --git a/library/Graphite/Graphing/GraphiteWebClient.php b/library/Graphite/Graphing/GraphiteWebClient.php
index b06b6ce..982a2af 100644
--- a/library/Graphite/Graphing/GraphiteWebClient.php
+++ b/library/Graphite/Graphing/GraphiteWebClient.php
@@ -2,10 +2,10 @@
 
 namespace Icinga\Module\Graphite\Graphing;
 
+use GuzzleHttp\Client;
+use GuzzleHttp\ClientInterface;
+use GuzzleHttp\Psr7\Request;
 use Icinga\Web\Url;
-use iplx\Http\Client;
-use iplx\Http\ClientInterface;
-use iplx\Http\Request;
 
 /**
  * HTTP interface to Graphite Web
diff --git a/library/Graphite/Graphing/MetricsQuery.php b/library/Graphite/Graphing/MetricsQuery.php
index da05c17..93d0c90 100644
--- a/library/Graphite/Graphing/MetricsQuery.php
+++ b/library/Graphite/Graphing/MetricsQuery.php
@@ -71,7 +71,7 @@ class MetricsQuery implements Queryable, Filterable, Fetchable
         try {
             $this->base = $target instanceof MacroTemplate ? $target : new MacroTemplate((string) $target);
         } catch (InvalidArgumentException $e) {
-            throw new InvalidArgumentException('Bad target', $e);
+            throw new InvalidArgumentException('Bad target', $e->getCode(), $e);
         }
 
         return $this;
diff --git a/library/Graphite/Graphing/Template.php b/library/Graphite/Graphing/Template.php
index a030fb7..0950fed 100644
--- a/library/Graphite/Graphing/Template.php
+++ b/library/Graphite/Graphing/Template.php
@@ -203,6 +203,7 @@ class Template
                 }
             }
             unset($_);
+            assert(isset($nextCurveName), 'loop did not initialize variable $nextCurveName');
 
             $allowedNextCurveMetricsPerCurrentCurveName = [];
             foreach ($currentCombination as $currentCurveName => $currentCurveMetric) {