Refactor environment variable loading using pydantic-settings

.env.example

@@ -1,8 +1,9 @@
 PORT=8000
 IP_ADDRESS="localhost"
-SMTP_SERVER ='smtp.gmail.com'
-EMAIL=your-email
-EMAIL_PW=email-password
-EMAIL_RECEIVER=email-to-receive-surf-report
-COMMAND=localhost:8000
-SUBJECT='Surf Report'
+SMTP_SERVER="smtp.gmail.com"
+SMTP_PORT=587
+EMAIL="your-email"
+EMAIL_PW="email-password"
+EMAIL_RECEIVER="email-to-receive-surf-report"
+COMMAND="localhost:8000"
+SUBJECT="Surf Report"

requirements.txt

@@ -7,3 +7,6 @@ python-dotenv==1.0.1
 Requests==2.32.2
 requests_cache==1.2.0
 retry_requests==2.0.0
+pydantic==2.7.1
+pydantic-settings==2.2.1
+email-validator==2.1.1

src/cli.py

@@ -2,10 +2,10 @@
 Main module
 """
 
-import os
 import sys
+from pathlib import Path
 
-sys.path.append(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+sys.path.append(str(Path(__file__).parent.parent))
 
 from src import api, helper
 

src/send_email.py

@@ -2,41 +2,29 @@
 Module to send surf report emails
 """
 
-import os
 import smtplib
 import subprocess
 from email.mime.multipart import MIMEMultipart
 from email.mime.text import MIMEText
 
-from dotenv import load_dotenv
+from settings import EmailSettings
 
 # Load environment variables from .env file
-load_dotenv(override=True)
-
-# Email server configuration
-SMTP_SERVER = os.getenv("SMTP_SERVER")
-PORT = 587  # Port for TLS connection
-
-# Sender's email credentials
-SENDER_EMAIL = os.getenv("EMAIL")
-PASSWORD = os.getenv("EMAIL_PW")
-
-# Receiver's email
-RECEIVER_EMAIL = os.getenv("EMAIL_RECEIVER")
+env = EmailSettings()
 
 # Create a multipart message and set headers
 message = MIMEMultipart()
-message["From"] = SENDER_EMAIL
-message["To"] = RECEIVER_EMAIL
-message["Subject"] = os.getenv("SUBJECT")
+message["From"] = env.EMAIL
+message["To"] = env.EMAIL_RECEIVER
+message["Subject"] = env.SUBJECT
 
 
 def send_user_email():
     """
     Sends user an email
     """
     SURF = subprocess.run(
-        ["curl", os.getenv("COMMAND")],
+        ["curl", env.COMMAND],
         capture_output=True,
         text=True,
         check=True,
@@ -48,12 +36,12 @@ def send_user_email():
     message.attach(MIMEText(BODY, "plain"))
 
     # Connect to the SMTP server
-    with smtplib.SMTP(SMTP_SERVER, PORT) as server:
+    with smtplib.SMTP(env.SMTP_SERVER, env.SMTP_PORT) as server:
         server.starttls()  # Secure the connection
-        server.login(SENDER_EMAIL, PASSWORD)
+        server.login(env.EMAIL, env.EMAIL_PW)
         text = message.as_string()
-        server.sendmail(SENDER_EMAIL, RECEIVER_EMAIL, text)
+        server.sendmail(env.EMAIL, env.EMAIL_RECEIVER, text)
         print("Email sent successfully.")
 
-
-send_user_email()
+if __name__ == "__main__":
+    send_user_email()

src/server.py

@@ -3,11 +3,10 @@
 """
 
 import asyncio
-import os
 import subprocess
 import urllib.parse
 
-from dotenv import dotenv_values, load_dotenv
+from pathlib import Path
 from flask import (
     Flask,
     render_template,
@@ -17,21 +16,25 @@
 )
 from flask_cors import CORS
 
+from settings import ServerSettings
+
 # Load environment variables from .env file
-load_dotenv(override=True)
+env = ServerSettings()
 
 app = Flask(__name__)
 CORS(app)
 
 
 @app.route("/help")
 def serve_help():
-    return send_from_directory("../", "help.txt")
+    return send_from_directory(
+        f"{str(Path(__file__).parent)}/", "help.txt"
+    )
 
 
 @app.route("/home")
 def serve_index():
-    return render_template("index.html", env_vars=dict(dotenv_values()))
+    return render_template("index.html", env_vars=env.model_dump())
 
 
 @app.route("/script.js")
@@ -78,4 +81,4 @@ async def run_subprocess():
 
 
 if __name__ == "__main__":
-    app.run(host="0.0.0.0", port=os.getenv("PORT"))
+    app.run(host="0.0.0.0", port=env.PORT)

src/settings.py

@@ -0,0 +1,45 @@
+from pathlib import Path
+from typing import Literal, Union
+
+from pydantic import EmailStr, Field, IPvAnyAddress
+from pydantic_settings import BaseSettings, SettingsConfigDict
+
+
+class CommonSettings(BaseSettings):
+    """
+    Base class for defining common settings.
+    model_config (SettingsConfigDict)Configuration dictionary
+    for specifying the settings file and encoding.
+    """
+    model_config = SettingsConfigDict(
+        env_file=f"{Path(__file__).parent.parent}/.env",
+        env_file_encoding="utf-8",
+        extra="ignore",
+    )
+
+
+class ServerSettings(CommonSettings):
+    """
+    Class for defining server env settings.
+    """
+
+    PORT: int = Field(default=8000)
+    IP_ADDRESS: Union[IPvAnyAddress | Literal["localhost"]] = Field(
+        default="localhost"
+    )
+
+
+class EmailSettings(ServerSettings):
+    """
+    Class for defining email env settings.
+    """
+
+    SMTP_SERVER: str = Field(default="smtp.gmail.com")  # default gmail server
+    SMTP_PORT: int = Field(default=587)  # default 587
+    EMAIL: EmailStr  # required
+    EMAIL_PW: str  # required
+    EMAIL_RECEIVER: EmailStr  # required
+    COMMAND: str = Field(
+        default_factory=lambda cls: f"{cls.IP_ADDRESS}:{cls.PORT}"
+    )
+    SUBJECT: str = Field(default="Surf Report")