adding webhook controller

src/main/java/com/abnov/infisicalbridge/infisical/InfisicalWebhookController.java

@@ -0,0 +1,37 @@
+package com.abnov.infisicalbridge.infisical;
+
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestHeader;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+
+@RestController
+@RequestMapping("/webhook")
+@RequiredArgsConstructor
+@Slf4j
+public class InfisicalWebhookController {
+    private final InfisicalSignatureVerifier signatureVerifier;
+
+    @PostMapping
+    public void handleWebhook(
+            @RequestBody String payload,
+            @RequestHeader(value = "X-Infisical-Signature", required = false) String signature) {
+        // Check if signature header is present
+        if (signature == null || signature.isEmpty()) {
+            log.error("Missing signature header");
+            return;
+        }
+
+        // Verify the signature
+        if (!signatureVerifier.verifySignature(payload, signature, "demoa")) {
+            log.error("Invalid signature");
+            return;
+        }
+
+        log.info("Webhook received and verified: {}", payload);
+    }
+}