Adds environment variable alternatives to config items (#210)

* Adds environment variable alternatives to config items

* Updates changelog

* Fixes grammar

* Changes based on PR feedback

* Fixes import sorting

* Fixes tests

* Reverts previous change and black formatting

CHANGELOG.md

@@ -4,6 +4,10 @@ If there is no "Upgrading" header for that version, no post-upgrade actions need
 
 
 ## Upcoming
+### New Features
+- Added environment variable alternatives for many configuration items
+([#210](https://github.com/jdholtz/auto-southwest-check-in/pull/210))
+
 ### Bug Fixes
 - Fix failed logins not reporting the correct error
 ([#189](https://github.com/jdholtz/auto-southwest-check-in/issues/189))

CONFIGURATION.md

@@ -5,6 +5,9 @@ file can be found at [config.example.json](config.example.json)
 Auto-Southwest Check-In supports both global configuration and account/reservation-specific configuration. See
 [Accounts and Reservations](#accounts-and-reservations) for more information.
 
+**Note**: Many configuration items may also be configured via environment variables (except for account and 
+reservation specific configurations).
+
 ## Table of Contents
 - [Fare Check](#fare-check)
 - [Notifications](#notifications)
@@ -19,7 +22,9 @@ Auto-Southwest Check-In supports both global configuration and account/reservati
 
 ## Fare Check
 Default: true \
-Type: Boolean
+Type: Boolean \
+Environment Variable: `AUTO_SOUTHWEST_CHECK_IN_CHECK_FARES`
+> Using the environment variable will override the applicable setting in `config.json`.
 
 In addition to automatically checking in, check for price drops on an interval
 (see [Retrieval Interval](#retrieval-interval)). If a lower fare is found, the user will be notified.
@@ -34,7 +39,10 @@ In addition to automatically checking in, check for price drops on an interval
 ## Notifications
 ### Notification URLs
 Default: [] \
-Type: String or List
+Type: String or List \
+Environment Variable: `AUTO_SOUTHWEST_CHECK_IN_NOTIFICATION_URL`
+> When using the environment variable, you may only specify a single URL.
+> If you are also using `config.json`, it will append the URL as long as it's not a duplicate.
 
 Users can be notified on successful and failed check-ins. This is done through the [Apprise library][0].
 To start, first gather the service URL you want to send notifications to (information on how to create
@@ -57,7 +65,9 @@ If you have more than one service you want to send notifications to, you can put
 
 ### Notification Level
 Default: 1 \
-Type: Integer
+Type: Integer \
+Environment Variable: `AUTO_SOUTHWEST_CHECK_IN_NOTIFICATION_LEVEL`
+> Using the environment variable will override the applicable setting in `config.json`.
 
 You can also select the level of notifications you want to receive.
 ```json
@@ -76,7 +86,9 @@ $ python3 southwest.py --test-notifications
 
 ## Browser Path
 Default: The path to your Chrome or Chromium browser (if installed) \
-Type: String
+Type: String \
+Environment Variable: `AUTO_SOUTHWEST_CHECK_IN_BROWSER_PATH`
+> Using the environment variable will override the applicable setting in `config.json`.
 
 If you use another Chromium-based browser besides Google Chrome or Chromium (such as Brave), you need to specify the path to
 the browser executable.
@@ -90,7 +102,9 @@ the browser executable.
 
 ## Retrieval Interval
 Default: 24 hours \
-Type: Integer
+Type: Integer \
+Environment Variable: `AUTO_SOUTHWEST_CHECK_IN_RETRIEVAL_INTERVAL`
+> Using the environment variable will override the applicable setting in `config.json`.
 
 You can choose how often the script checks for lower fares on scheduled flights (in hours). Additionally, this
 interval will also determine how often the script checks for new flights if login credentials are provided. To
@@ -108,7 +122,11 @@ account and reservation.
 
 ### Accounts
 Default: [] \
-Type: List
+Type: List \
+Environment Variables:
+ - `AUTO_SOUTHWEST_CHECK_IN_USERNAME`
+ - `AUTO_SOUTHWEST_CHECK_IN_PASSWORD`
+> When using the environment variables, you may only specify a single set of credentials.
 
 You can add more accounts to the script, allowing you to run multiple accounts at the same time and/or not
 provide a username and password as arguments.
@@ -123,7 +141,12 @@ provide a username and password as arguments.
 
 ### Reservations
 Default: [] \
-Type: List
+Type: List \
+Environment Variables:
+ - `AUTO_SOUTHWEST_CHECK_IN_CONFIRMATION_NUMBER`
+ - `AUTO_SOUTHWEST_CHECK_IN_FIRST_NAME`
+ - `AUTO_SOUTHWEST_CHECK_IN_LAST_NAME`
+> When using the environment variables, you may only specify a single reservation.
 
 You can also add more reservations to the script, allowing you check in to multiple reservations in the same instance
 and/or not provide reservation information as arguments.

README.md

@@ -62,8 +62,8 @@ Alternatively, you can log in to your account, which will automatically check yo
 ```shell
 python3 southwest.py USERNAME PASSWORD
 ```
-**Note**: If any arguments contain special characters, make sure to escape them so they are passed into
-the script correctly.
+**Note**: If any arguments contain special characters, make sure to escape them or use
+environment variables so they are passed into the script correctly.
 
 For the full usage of the script, run:
 ```shell
@@ -97,7 +97,7 @@ You can optionally attach a configuration file to the container by adding the
 
 **Note**: The recommended restart policy for the container is `on-failure` or `no`
 
-#### Docker Compose Example
+#### Docker Compose Example Using Config
 ```yaml
 services:
   auto-southwest:
@@ -108,6 +108,18 @@ services:
       - /full-path/to/config.json:/app/config.json
 ```
 
+#### Docker Compose Example Using Environment Variables
+```yaml
+services:
+  auto-southwest:
+    image: jdholtz/auto-southwest-check-in
+    container_name: auto-southwest
+    restart: on-failure
+    environment:
+      - AUTO_SOUTHWEST_CHECK_IN_USERNAME=MyUsername
+      - AUTO_SOUTHWEST_CHECK_IN_PASSWORD=TopsyKretts
+```
+
 Additional information on the Docker container can be found in the [public repository][5].
 
 ## Configuration

lib/config.py

@@ -1,10 +1,11 @@
 import json
+import os
 import sys
 from pathlib import Path
 from typing import Any, Dict, List
 
 from .log import get_logger
-from .utils import NotificationLevel
+from .utils import NotificationLevel, is_truthy
 
 # Type alias for JSON
 JSON = Dict[str, Any]
@@ -108,6 +109,7 @@ def initialize(self) -> JSON:
 
         try:
             config = self._read_config()
+            config = self._read_env_vars(config)
             self._parse_config(config)
         except (ConfigError, json.decoder.JSONDecodeError) as err:
             print("Error in configuration file:")
@@ -144,6 +146,75 @@ def _read_config(self) -> JSON:
 
         return config
 
+    def _read_env_vars(self, config: JSON) -> JSON:
+        logger.debug("Reading configuration from environment variables")
+        # Check Fares
+        check_fares = os.getenv("AUTO_SOUTHWEST_CHECK_IN_CHECK_FARES")
+        if check_fares:
+            try:
+                config["check_fares"] = is_truthy(check_fares)
+            except ValueError as err:
+                raise ConfigError("Error parsing 'AUTO_SOUTHWEST_CHECK_IN_CHECK_FARES'") from err
+
+        # Notification URL
+        notification_url = os.getenv("AUTO_SOUTHWEST_CHECK_IN_NOTIFICATION_URL")
+        if notification_url:
+            config.setdefault("notification_urls", [])
+            if isinstance(config["notification_urls"], str):
+                config["notification_urls"] = [config["notification_urls"]]
+            if not isinstance(config["notification_urls"], list):
+                raise ConfigError("'notification_urls' must be a string or a list")
+            if notification_url not in config["notification_urls"]:
+                config["notification_urls"].append(notification_url)
+
+        # Notification Level
+        notification_level = os.getenv("AUTO_SOUTHWEST_CHECK_IN_NOTIFICATION_LEVEL")
+        if notification_level:
+            try:
+                config["notification_level"] = int(notification_level)
+            except ValueError as err:
+                raise ConfigError(
+                    "'AUTO_SOUTHWEST_CHECK_IN_NOTIFICATION_LEVEL' must be an integer"
+                ) from err
+
+        # Browser Path
+        browser_path = os.getenv("AUTO_SOUTHWEST_CHECK_IN_BROWSER_PATH")
+        if browser_path:
+            config["browser_path"] = browser_path
+
+        # Retrieval Interval
+        retrieval_interval = os.getenv("AUTO_SOUTHWEST_CHECK_IN_RETRIEVAL_INTERVAL")
+        if retrieval_interval:
+            try:
+                config["retrieval_interval"] = int(retrieval_interval)
+            except ValueError as err:
+                raise ConfigError(
+                    "'AUTO_SOUTHWEST_CHECK_IN_RETRIEVAL_INTERVAL' must be an integer"
+                ) from err
+
+        # Account credentials
+        username = os.getenv("AUTO_SOUTHWEST_CHECK_IN_USERNAME")
+        password = os.getenv("AUTO_SOUTHWEST_CHECK_IN_PASSWORD")
+        if username and password:
+            new_credentials = {"username": username, "password": password}
+            config.setdefault("accounts", [])
+            config["accounts"].append(new_credentials)
+
+        # Reservation information
+        confirmation_number = os.getenv("AUTO_SOUTHWEST_CHECK_IN_CONFIRMATION_NUMBER")
+        first_name = os.getenv("AUTO_SOUTHWEST_CHECK_IN_FIRST_NAME")
+        last_name = os.getenv("AUTO_SOUTHWEST_CHECK_IN_LAST_NAME")
+        if confirmation_number and first_name and last_name:
+            new_reservation = {
+                "confirmationNumber": confirmation_number,
+                "firstName": first_name,
+                "lastName": last_name,
+            }
+            config.setdefault("reservations", [])
+            config["reservations"].append(new_reservation)
+
+        return config
+
     def _parse_config(self, config: JSON) -> None:
         super()._parse_config(config)
 

lib/utils.py

@@ -2,7 +2,7 @@
 import logging
 import time
 from enum import IntEnum
-from typing import Any, Dict
+from typing import Any, Dict, Union
 
 import requests
 
@@ -73,3 +73,26 @@ class FlightChangeError(Exception):
 class NotificationLevel(IntEnum):
     INFO = 1
     ERROR = 2
+
+
+def is_truthy(arg: Union[bool, int, str]) -> bool:
+    """
+    Convert "truthy" strings into Booleans.
+
+    Examples:
+        >>> is_truthy('yes')
+        True
+
+    Args:
+        arg: Truthy value (True values are y, yes, t, true, on and 1; false values are n, no,
+        f, false, off and 0. Raises ValueError if val is anything else.
+    """
+    if isinstance(arg, bool):
+        return arg
+
+    val = str(arg).lower()
+    if val in ("y", "yes", "t", "true", "on", "1"):
+        return True
+    if val in ("n", "no", "f", "false", "off", "0"):
+        return False
+    raise ValueError(f"Invalid truthy value: `{arg}`")