jams-server: prevent server start if CA failed to load

If the config.json file is corrupted, JAMS may start even though its CA
is null. In this state, the server cannot authenticate any user and is
not operational.

Ticket: https://redmine.savoirfairelinux.com/issues/7668
Change-Id: I61e69200af1089a085991176fa6bb6273ecc2e82

jams-server/src/main/java/net/jami/jams/server/Server.java

@@ -168,6 +168,10 @@ public class Server {
         certificateAuthority =
                 CryptoEngineLoader.loadCertificateAuthority(
                         serverSettings.getCaConfiguration(), dataStore);
+        if (certificateAuthority == null) {
+            log.error("Could not load certificate authority - this is critical");
+            System.exit(1);
+        }
         userAuthenticationModule =
                 AuthModuleLoader.loadAuthenticationModule(dataStore, certificateAuthority);
 

jams-server/src/main/java/net/jami/jams/server/startup/CryptoEngineLoader.java

@@ -51,7 +51,7 @@ public class CryptoEngineLoader {
                     "Loaded X509 Engine - please make sure it is initialized before using it to sign requests!");
             return certificateAuthority;
         } catch (Exception e) {
-            log.error("Unable to load X509 Engine!");
+            log.error("Load X509 Engine failed with error:", e);
             return null;
         }
     }