Revize 81dbb479

Re #8569 Checking presence of OpenSSL during init

app.py

@@ -6 +6 @@
 from src.config import configuration
 from src.config.connection_provider import ConnectionProvider
 from src.controllers.certificates_controller import CertController
+from src.services.cryptography import CryptographyService, CryptographyException
 
 
 class X509ManagementApp(Flask):
 
     def run(self, host=None, port=None, debug=None, load_dotenv=True, **options):
         with self.app_context():
-            initialize_app()
+            if not initialize_app():
+                return
         super(X509ManagementApp, self).run(host=host, port=port, debug=debug, load_dotenv=load_dotenv, **options)
 
 
@@ -55 +57 @@
     return certificate_controller.get_certificate_trust_chain_by_id(id)
 
 
-def initialize_app():
+def initialize_app() -> bool:
+    """
+    Initializes the application
+        -   configure dependency injection
+        -   check whether OpenSSL is on the system
+    :return: boolean flag indicating whether initialization was successfull or not
+    """
     global certificate_controller
 
     injector = Injector([configuration.configure_default, ConnectionProvider])
     certificate_controller = injector.get(CertController)
 
+    # There's a little dependency on the CryptoService, which is not a pretty thing from
+    # architectural point of view. However it is only a minimal piece of code and
+    # it makes sense to do it in this way instead of trying to run openssl via subprocess here
+    cryptography_service = injector.get(CryptographyService)
+    try:
+        # if version string is returned, OpenSSL is present on the system
+        print(f"Using {cryptography_service.get_openssl_version()}")
+        # TODO log the version instead of prining it out
+        return True
+    except CryptographyException:
+        # If getting the version string throws an exception the OpenSSL is not available
+        print("OpenSSL was not located on the system. Application will now exit.")
+        # TODO add logging here
+        return False
+
 
 if __name__ == '__main__':
     app_host = "0.0.0.0"