Update app.py

app.py

@@ -1,20 +1,54 @@
 """
-Radar Data Downloader via Gradio
-==================================
+Radar Data Downloader with Station Selector via Gradio
+========================================================
 
 This script mimics part of Supercell Wx’s functionality by downloading the latest
-radar data file from public AWS S3 buckets. It uses boto3 in unsigned mode,
-so no AWS credentials are required. The Gradio interface lets you select the
-data type, radar station, and date (in UTC, formatted as “YYYY‑MM‑DD”) to download a file.
+radar data file from public AWS S3 buckets. It now downloads the list of radar sites
+from the Supercell Wx GitHub repository and provides a dropdown for station selection.
+
+Ensure you have installed required packages:
+    pip install gradio boto3 requests
 """
 
 import datetime
 import io
+import json
 
 import boto3
 from botocore import UNSIGNED
 from botocore.client import Config
 import gradio as gr
+import requests
+
+
+def get_station_list():
+    """
+    Downloads and parses the radar_sites.json file from the Supercell Wx GitHub repository.
+    Returns a sorted list of station identifiers.
+    """
+    # URL for the raw radar_sites.json file from the Supercell Wx repository.
+    url = "https://raw.githubusercontent.com/dpaulat/supercell-wx/develop/data/radar_sites.json"
+    try:
+        response = requests.get(url)
+        response.raise_for_status()
+        data = response.json()
+    except Exception as e:
+        # Fallback: return a default list if there is an error.
+        print(f"Error fetching station list: {e}")
+        return ["KTLX", "KDOX", "KBMX"]
+    
+    # The JSON is expected to be a list of station objects.
+    # Extract the station identifier. Assuming each object has a "station" or "id" field.
+    # Checking common patterns:
+    stations = []
+    for item in data:
+        # Try several keys:
+        if "station" in item:
+            stations.append(item["station"].upper())
+        elif "id" in item:
+            stations.append(item["id"].upper())
+    stations = sorted(list(set(stations)))
+    return stations
 
 
 def fetch_latest_radar_data(radar_type, station, date_str):
@@ -95,20 +129,23 @@ def fetch_latest_radar_data(radar_type, station, date_str):
     return summary
 
 
-# Create the Gradio interface using new component classes.
+# Get station list at startup.
+station_list = get_station_list()
+
+# Create the Gradio interface using updated component classes.
 interface = gr.Interface(
     fn=fetch_latest_radar_data,
     inputs=[
         gr.Radio(choices=["Level 2", "Level 3"], label="Radar Data Type"),
-        gr.Textbox(value="KTLX", label="Radar Station (e.g. KTLX)"),
+        gr.Dropdown(choices=station_list, label="Select Radar Station"),
         gr.Textbox(value=datetime.datetime.utcnow().strftime("%Y-%m-%d"), label="Date (YYYY-MM-DD)")
     ],
     outputs="text",
     title="Radar Data Downloader",
     description=(
         "This tool downloads the latest radar data file from public AWS S3 buckets "
-        "used by Supercell Wx. Choose a radar data type (Level 2 or Level 3), enter a "
-        "radar station (e.g. KTLX), and a date (UTC). In future iterations, you can add "
+        "used by Supercell Wx. Choose a radar data type (Level 2 or Level 3), select a "
+        "radar station, and enter a date (UTC). In future iterations, you can add "
         "visualization using OpenStreetMap (which requires no API keys)."
     )
 )