Fix #13: Enhanced error handling

main.py

@@ -1,7 +1,7 @@
 import datetime
 import requests
 import string
-from flask import Flask, render_template, request, redirect, url_for
+from flask import Flask, render_template, request, redirect, url_for , flash
 import os
 from dotenv import load_dotenv
 load_dotenv()
@@ -14,13 +14,16 @@
 
 app = Flask(__name__)
 
-
+app.secret_key = os.getenv("FLASK_SECRET_KEY" , "default_secret_key")
 # Display home page and get city name entered into search form
 @app.route("/", methods=["GET", "POST"])
 def home():
     if request.method == "POST":
         city = request.form.get("search")
-        return redirect(url_for("get_weather", city=city))
+        if not city:
+            flash("Please enter a city name." , "error")
+            return redirect(url_for("home"))
+        return redirect(url_for("get_weather" , city = city))
     return render_template("index.html")
 
 
@@ -33,32 +36,62 @@ def get_weather(city):
     current_date = today.strftime("%A, %B %d")
 
     # Get latitude and longitude for city
-    location_params = {
-        "q": city_name,
-        "appid": api_key,
-        "limit": 3,
-    }
-
-    location_response = requests.get(GEOCODING_API_ENDPOINT, params=location_params)
-    location_data = location_response.json()
-
-    # Prevent IndexError if user entered a city name with no coordinates by redirecting to error page
-    if not location_data:
-        return redirect(url_for("error"))
-    else:
-        lat = location_data[0]['lat']
-        lon = location_data[0]['lon']
-
-    # Get OpenWeather API data
-    weather_params = {
-        "lat": lat,
-        "lon": lon,
-        "appid": api_key,
-        "units": "metric",
-    }
-    weather_response = requests.get(OWM_ENDPOINT, weather_params)
-    weather_response.raise_for_status()
-    weather_data = weather_response.json()
+    try:
+        location_params = {
+            "q": city_name,
+            "appid": api_key,
+            "limit": 3,
+        }
+
+        location_response = requests.get(GEOCODING_API_ENDPOINT, params=location_params)
+        location_response.raise_for_status()
+        location_data = location_response.json()
+
+        # Prevent IndexError if user entered a city name with no coordinates by redirecting to error page
+        if not location_data:
+            flash("City not found. Please enter a valid city name." , "error")
+            return redirect(url_for("error"))
+        else:
+            lat = location_data[0]['lat']
+            lon = location_data[0]['lon']
+
+        # Get OpenWeather API data
+        weather_params = {
+            "lat": lat,
+            "lon": lon,
+            "appid": api_key,
+            "units": "metric",
+        }
+        weather_response = requests.get(OWM_ENDPOINT, weather_params , timeout=5)
+        weather_response.raise_for_status()
+        weather_data = weather_response.json()
+        # Get five-day weather forecast data
+        forecast_response = requests.get(OWM_FORECAST_ENDPOINT, weather_params , timeout=5)
+        forecast_data = forecast_response.json()
+
+    except requests.exceptions.Timeout:
+        flash("The request to the weather service timed out. Please try again later." , "error")
+        return redirect(url_for("home"))
+
+    except requests.exceptions.ConnectionError:
+        flash("Network error occurred while trying to connect to the weather service. Please check your internet connection and try again." , "error")
+        return redirect(url_for("home"))
+
+    except requests.exceptions.HTTPError as http_err:
+        if http_err.response.status_code == 404:
+            flash("City not found. Please enter a valid city name." , "error")
+            return redirect(url_for("error"))
+        elif http_err.response.status_code == 401:
+            flash("Invalid API key. Please check your API key and try again." , "error")
+            return redirect(url_for("home"))
+        else:
+            flash(f"An error occurred: {http_err}" , "error")
+        return redirect(url_for("home"))
+
+    except Exception as e:
+        flash(f"An unexpected error occurred: {e}" , "error")
+        return redirect(url_for("home"))
+
 
     # Get current weather data
     current_temp = round(weather_data['main']['temp'])
@@ -67,9 +100,6 @@ def get_weather(city):
     max_temp = round(weather_data['main']['temp_max'])
     wind_speed = weather_data['wind']['speed']
 
-    # Get five-day weather forecast data
-    forecast_response = requests.get(OWM_FORECAST_ENDPOINT, weather_params)
-    forecast_data = forecast_response.json()
 
     # Make lists of temperature and weather description data to show user
     five_day_temp_list = [round(item['main']['temp']) for item in forecast_data['list'] if '12:00:00' in item['dt_txt']]

templates/index.html

@@ -15,6 +15,19 @@ <h1> Weather </h1>
                 <div class="background">
                     <img src="/static/assets/weather-home-background.jpg" alt="" class="desktop-background">
                 </div>
+                {% with messages = get_flashed_messages(with_categories=true) %}
+                {% if messages %}
+                    {% for category, message in messages %}
+                    <div class="alert-{{ category }}">
+                        {{ message }}
+                    </div>
+                    {% endfor %}
+                {% endif %}
+                {% endwith %}
+
+                <form action="/" method="POST">
+                ...
+                </form>
                 <div class="search-bar"> 
                     <img class="search-icon" src="/static/assets/search.png" alt="">
                     <form class="search" action="" autocomplete="off" method="post">