Add exit codes for errors

Resolves #10

Signed-off-by: Gregers Gram Rygg <gregers.gram.rygg@nordicsemi.no>

Author: gregersrygg

src/nrfcredstore/cli.py

@@ -11,6 +11,11 @@
 KEY_TYPES = KEY_TYPES_OR_ANY.copy()
 KEY_TYPES.remove('ANY')
 
+ERR_UNKNOWN = 1
+ERR_NO_AT_CLIENT = 10
+ERR_AT_COMMAND = 11
+ERR_TIMEOUT = 12
+ERR_SERIAL = 13
 
 def parse_args(in_args):
     parser = argparse.ArgumentParser(description='Manage certificates stored in a cellular modem.')
@@ -89,6 +94,10 @@ def exec_cmd(args, credstore):
         print(f'New private key generated in secure tag {args.tag}')
         print(f'Wrote CSR in DER format to {args.file.name}')
 
+def exit_with_msg(exitcode, msg):
+    print(msg)
+    exit(exitcode)
+
 def main(in_args, credstore):
     at_client = credstore.at_client
     try:
@@ -98,14 +107,16 @@ def main(in_args, credstore):
             at_client.verify()
             at_client.enable_error_codes()
         exec_cmd(args, credstore)
-    except serial.SerialException as err:
-        print(f'Serial error: {err}')
     except NoATClientException:
-        print('The device does not respond to AT commands. Please flash at_client sample.')
+        exit_with_msg(ERR_NO_AT_CLIENT, 'The device does not respond to AT commands. Please flash at_client sample.')
     except ATCommandError as err:
-        print(err)
+        exit_with_msg(ERR_AT_COMMAND, err)
     except TimeoutError as err:
-        print('The device did not respond in time. Please try again.')
+        exit_with_msg(ERR_TIMEOUT, 'The device did not respond in time. Please try again.')
+    except serial.SerialException as err:
+        exit_with_msg(ERR_SERIAL, f'Serial error: {err}')
+    except Exception as err:
+        exit_with_msg(ERR_UNKNOWN, f'Unhandled Error: {err}')
 
 def run():
     main(sys.argv[1:], CredStore(ATClient(serial.Serial())))

tests/test_cli.py

@@ -1,10 +1,11 @@
 import pytest
 
 from unittest.mock import Mock, ANY, patch
+from serial import SerialException
 from nrfcredstore.cli import main
 
 from nrfcredstore.credstore import CredType
-from nrfcredstore.exceptions import NoATClientException
+from nrfcredstore.exceptions import NoATClientException, ATCommandError
 
 # pylint: disable=no-self-use
 class TestCli():
@@ -47,7 +48,8 @@ def test_at_client_verify(self, credstore, at_client, offline, empty_cred_list):
     @patch('builtins.print')
     def test_at_client_verify_fail(self, mock_print, credstore, at_client):
         at_client.verify.side_effect = NoATClientException()
-        main(['fakedev', 'list'], credstore)
+        with pytest.raises(SystemExit) as e:
+            main(['fakedev', 'list'], credstore)
         assert 'does not respond to AT commands' in mock_print.call_args[0][0]
 
     def test_at_client_enable_error_codes(self, credstore, at_client, offline, empty_cred_list):
@@ -103,3 +105,38 @@ def test_generate_file(self, mock_file, credstore, offline):
         credstore.keygen.return_value = True
         main(['fakedev', 'generate', '123', 'foo.der'], credstore)
         mock_file.assert_called_with('foo.der', 'wb', ANY, ANY, ANY)
+
+    def test_no_at_client_exit_code(self, credstore, at_client):
+        at_client.verify.side_effect = NoATClientException()
+        with pytest.raises(SystemExit) as e:
+            main(['fakedev', 'list'], credstore)
+        assert e.type == SystemExit
+        assert e.value.code == 10
+
+    def test_at_command_error_exit_code(self, credstore, at_client):
+        at_client.verify.side_effect = ATCommandError()
+        with pytest.raises(SystemExit) as e:
+            main(['fakedev', 'list'], credstore)
+        assert e.type == SystemExit
+        assert e.value.code == 11
+
+    def test_timeout_error_exit_code(self, credstore, at_client):
+        at_client.verify.side_effect = TimeoutError()
+        with pytest.raises(SystemExit) as e:
+            main(['fakedev', 'list'], credstore)
+        assert e.type == SystemExit
+        assert e.value.code == 12
+
+    def test_serial_exception_exit_code(self, credstore, at_client):
+        at_client.connect.side_effect = SerialException()
+        with pytest.raises(SystemExit) as e:
+            main(['fakedev', 'list'], credstore)
+        assert e.type == SystemExit
+        assert e.value.code == 13
+
+    def test_unhandled_exception_exit_code(self, credstore, at_client):
+        at_client.verify.side_effect = Exception()
+        with pytest.raises(SystemExit) as e:
+            main(['fakedev', 'list'], credstore)
+        assert e.type == SystemExit
+        assert e.value.code == 1