Fix plugin when libcrypto override variable is not set

calibre-plugin/__init__.py

@@ -285,18 +285,23 @@ def initialize(self):
 
  # Okay, now all the modules are available, import the Adobe modules.
 
+
+ # On some systems, like NixOS, the path to libcrypto and libssl 
+ # isn't autodetected correctly. To fix this, allow overriding
+ # these paths using environment variables.
  # Crucial to import first, as libadobe imports oscrypto as well
 
- libcrypto_path = os.environ["ACSM_LIBCRYPTO"]
- libssl_path = os.environ["ACSM_LIBSSL"]
+ libcrypto_path = os.getenv("ACSM_LIBCRYPTO", None)
+ libssl_path = os.getenv("ACSM_LIBSSL", None)
 
- if os.path.exists(libcrypto_path) and os.path.exists(libssl_path):
- import oscrypto
+ if libcrypto_path is not None and libssl_path is not None:
+ if os.path.exists(libcrypto_path) and os.path.exists(libssl_path):
+ import oscrypto # type: ignore
 
- oscrypto.use_openssl(
- libcrypto_path = libcrypto_path,
- libssl_path = libssl_path,
- )
+  oscrypto.use_openssl(
+  libcrypto_path = libcrypto_path,
+  libssl_path = libssl_path,
+  )
 
 
  from libadobe import createDeviceKeyFile, update_account_path, sendHTTPRequest