Merge pull request #170 from realpython/python-web-applications

Python web applications

python-web-applications/app.yaml

+runtime: python38
\ No newline at end of file

python-web-applications/main.py

+from flask import Flask
+from flask import request
+
+app = Flask(__name__)
+
+
+def fahrenheit_from(celsius):
+    """Convert Celsius to Fahrenheit degrees."""
+    try:
+        fahrenheit = float(celsius) * 9 / 5 + 32
+        fahrenheit = round(fahrenheit, 3)  # Round to three decimal places
+        return str(fahrenheit)
+    except ValueError:
+        return "invalid input"
+
+
+@app.route("/")
+def index():
+    celsius = request.args.get("celsius", "")
+    if celsius:
+        fahrenheit = fahrenheit_from(celsius)
+    else:
+        fahrenheit = ""
+    return (
+        """<form action="" method="get">
+                Celsius temperature: <input type="text" name="celsius">
+                <input type="submit" value="Convert to Fahrenheit">
+            </form>"""
+        + "Fahrenheit: "
+        + fahrenheit
+    )
+
+
+if __name__ == "__main__":
+    app.run(host="127.0.0.1", port=8080, debug=True)

python-web-applications/requirements.txt

+Flask==1.1.2