feat: implement transient caching for cURL responses

Author: hnccox

src/PrefillGravityForms/Controllers/BaseController.php

@@ -309,8 +309,15 @@ protected function getCurlHeaders(string $doelBinding = ''): array
         return array_filter($headers);
     }
 
-    protected function handleCurl(array $args): array
+    protected function handleCurl(array $args, ?string $transientKey = null): array
     {
+        if (is_string($transientKey) && 0 < strlen(trim($transientKey))) {
+            $cachedResponse = get_transient($transientKey);
+            if (is_array($cachedResponse) && [] !== $cachedResponse) {
+                return $cachedResponse;
+            }
+        }
+
         $curl = curl_init();
 
         try {
@@ -338,10 +345,14 @@ protected function handleCurl(array $args): array
 
             $decoded = json_decode($output, true);
 
-            if (! $decoded || json_last_error() !== JSON_ERROR_NONE) {
+            if (! is_array($decoded) || [] === $decoded || json_last_error() !== JSON_ERROR_NONE) {
                 throw new Exception('Something went wrong with decoding of the JSON output.', 500);
             }
 
+            if (is_string($transientKey) && 0 < strlen(trim($transientKey))) {
+                set_transient($transientKey, $decoded, HOUR_IN_SECONDS);
+            }
+
             return $decoded;
         } catch (Exception $e) {
             return [

src/PrefillGravityForms/Controllers/EnableUController.php

@@ -73,6 +73,9 @@ protected function request(string $bsn = '', string $doelBinding = '', string $e
             CURLOPT_HTTPHEADER => $this->getCurlHeaders($doelBinding),
         ];
 
-        return $this->handleCurl($curlArgs);
+        $hash = md5($curlArgs[CURLOPT_URL]);
+        $transientKey = (is_string($hash) && '' !== $hash) ? $hash : null;
+
+        return $this->handleCurl($curlArgs, $transientKey);
     }
 }

src/PrefillGravityForms/Controllers/PinkRoccadeController.php

@@ -75,6 +75,9 @@ protected function request(string $bsn = '', string $doelBinding = '', string $e
             CURLOPT_SSLKEY => $this->settings->getPrivateCertificate(),
         ];
 
-        return $this->handleCurl($curlArgs);
+        $hash = md5($curlArgs[CURLOPT_URL]);
+        $transientKey = (is_string($hash) && '' !== $hash) ? $hash : null;
+
+        return $this->handleCurl($curlArgs, $transientKey);
     }
 }

src/PrefillGravityForms/Controllers/VrijBRPController.php

@@ -75,6 +75,9 @@ protected function request(string $bsn = '', string $doelBinding = '', string $e
             CURLOPT_SSLKEY => $this->settings->getPrivateCertificate(),
         ];
 
-        return $this->handleCurl($curlArgs);
+        $hash = md5($curlArgs[CURLOPT_URL]);
+        $transientKey = (is_string($hash) && '' !== $hash) ? $hash : null;
+
+        return $this->handleCurl($curlArgs, $transientKey);
     }
 }

src/PrefillGravityForms/Controllers/WeAreFrankController.php

@@ -132,7 +132,10 @@ protected function request(array $data = []): array
             ],
         ];
 
-        return $this->handleCurl($curlArgs);
+        $hash = md5(json_encode($data));
+        $transientKey = (is_string($hash) && '' !== $hash) ? $hash : null;
+
+        return $this->handleCurl($curlArgs, $transientKey);
     }
 
     protected function getDefaultCurlArgs(): array