OZG-3322 load cert file only if exists

user-manager-server/src/main/java/de/itvsh/kop/user/MongodbCertificateLoader.java

 package de.itvsh.kop.user;
 
 import java.io.IOException;
+import java.io.InputStream;
 import java.nio.charset.Charset;
+import java.nio.file.Files;
+import java.nio.file.Paths;
 import java.security.KeyStore;
 import java.security.KeyStoreException;
 import java.security.NoSuchAlgorithmException;
@@ -13,6 +16,7 @@ import javax.enterprise.event.Observes;
 import org.apache.commons.io.IOUtils;
 import org.eclipse.microprofile.config.inject.ConfigProperty;
 
+import de.itvsh.kop.common.errorhandling.TechnicalException;
 import io.quarkus.runtime.StartupEvent;
 
 @ApplicationScoped
@@ -22,9 +26,21 @@ class MongodbCertificateLoader {
 	String mongoDbCaCert;
 
 	void onStart(@Observes StartupEvent ev) throws KeyStoreException, CertificateException, IOException, NoSuchAlgorithmException {
+		if(Files.exists(Paths.get(mongoDbCaCert))) {
 			System.out.println("loading cert...");
 			KeyStore keystore = KeyStore.getInstance("pkcs12");
-		keystore.load(IOUtils.toInputStream(mongoDbCaCert, Charset.defaultCharset()), null);
+			keystore.load(loadCaCrt(), null);
 			System.out.println("cert loaded");
+		} else {
+			System.out.println("cert file does not exists");
+		}
+	}
+
+	InputStream loadCaCrt() {
+		try {
+			return Files.newInputStream(Paths.get(mongoDbCaCert));
+		} catch (IOException e) {
+			throw new TechnicalException("Error loading caCert", e);
+		}
 	}
 }