Merge pull request #5 from Andy-Wu12/input-sanitization

Input sanitization

README.md

@@ -21,7 +21,14 @@ A Python script that helps check the online status of a list of user-provided we
 ## 2. Permanently
 1. Additionally install the dotenv module with `pip install python-dotenv`
 2. Modify the `config_template.json` file replacing the provided placeholders with your own data in the same format.
-   1. You can rename the file as you wish, just make sure to pass the correct name when calling the script.
+   1. The necessary configuration variables are:
+      1. "recipients": List of strings representing email addresses to send status updates to
+      2. "urls": List of strings representing website urls following same format as mentioned above
+      3. "emails_fail_only": Boolean representing whether to send emails only if a status check fails.
+         1. true indicates that you want the server to send an email when at least one status check fails.
+         2. This can be used with a lower "check_interval_secs" to prevent a flood of emails while also having the status check run constantly.
+      4. "check_interval_secs": Integer representing the number of seconds to delay another round of status checks.
+   2. You can rename the file as you wish, just make sure to pass the correct name when calling the script.
 3. Create a .env file with your gmail address and [APP PASSWORD](https://support.google.com/accounts/answer/185833?hl=en)
    1. If you want to use a different mailing client, you will have to modify `perm_server_status` with the 
    client's required configuration.

perm_server_status.py

@@ -16,6 +16,16 @@
 Config_Data = TypedDict('Config_Data', {'recipients': List[str], 'urls': List[str],
                                         'emails_fail_only': bool, 'check_interval_secs': int})
 
+ENV_EMAIL = 'USER_EMAIL'
+ENV_PASS = 'APP_PASSWORD'
+user_email = os.getenv(ENV_EMAIL)
+# Most likely necessary if using gmail or any other highly secure mailing client
+app_password = os.getenv(ENV_PASS)
+
+if not user_email or not app_password:
+    print(f'Set up your .env file with an email and password set to {ENV_EMAIL} and {ENV_PASS}, respectively')
+    sys.exit()
+
 
 def is_site_running(site_url: str):
     """Ping desired site
@@ -85,6 +95,11 @@ def run(config_data: Config_Data):
     downtime = config_data.get('check_interval_secs')
     emails_on_fail_only = config_data.get('emails_fail_only')
 
+    if None in [recipients, urls, downtime, emails_on_fail_only]:
+        print('A key is missing from your configuration!')
+        print('Please make sure you have all keys as shown in the configuration template.')
+        return None
+
     while True:
         url_statuses = []
         for url in urls:
@@ -101,22 +116,26 @@ def run(config_data: Config_Data):
 
 
 def parseConfigData(filepath: str):
-    with open(filepath) as f:
-        data = json.load(f)
+    try:
+        with open(filepath) as f:
+            data = json.load(f)
+    except (FileNotFoundError, json.JSONDecodeError) as e:
+        raise e
 
     return data
 
 
 if __name__ == "__main__":
-    user_email = os.getenv('USER_EMAIL')
-    # Most likely necessary if using gmail or any other highly secure mailing client
-    app_password = os.getenv('APP_PASSWORD')
-
     # Read in command line argument for config file path
     try:
         config_path = sys.argv[1]
     except IndexError:
         sys.exit("A filepath must be provided for the location of your configuration file!")
 
-    config_json = parseConfigData(config_path)
-    run(config_json)
+    try:
+        config_json = parseConfigData(config_path)
+        run(config_json)
+    except json.JSONDecodeError:
+        print("Error in parsing JSON. Please check your file for syntax errors!")
+    except FileNotFoundError:
+        print("The filename you entered does not exist!")