Update app.py

app.py

@@ -3,34 +3,52 @@ import pandas as pd
 import requests
 from io import BytesIO
 
-def convert_csv_to_parquet(csv_file=None, csv_url=None):
-    # Read the CSV file either from an uploaded file or from a URL
-    if csv_file is not None:
-        df = pd.read_csv(csv_file.name)
-    elif csv_url is not None:
-        response = requests.get(csv_url)
-        response.raise_for_status()  # Ensure the request was successful
-        df = pd.read_csv(BytesIO(response.content))
+def convert_file(input_file, file_url, conversion_type):
+    # Use the file provided by upload; if not, use the URL input.
+    if input_file is None and (file_url is None or file_url.strip() == ""):
+        raise ValueError("Please provide a file or a URL.")
+    
+    # Read the file into a DataFrame based on conversion type.
+    if input_file is not None:
+        file_path = input_file.name
+        if conversion_type == "CSV to Parquet":
+            df = pd.read_csv(file_path)
+        else:  # Parquet to CSV
+            df = pd.read_parquet(file_path)
     else:
-        raise ValueError("Either csv_file or csv_url must be provided")
+        response = requests.get(file_url)
+        response.raise_for_status()
+        if conversion_type == "CSV to Parquet":
+            df = pd.read_csv(BytesIO(response.content))
+        else:
+            df = pd.read_parquet(BytesIO(response.content))
     
-    # Optionally, perform any cleaning on the DataFrame here if needed
-
-    # Save the DataFrame as a Parquet file
-    output_file_path = "output.parquet"
-    df.to_parquet(output_file_path, index=False)
-
-    return output_file_path
+    # Save the converted file.
+    if conversion_type == "CSV to Parquet":
+        output_file = "output.parquet"
+        df.to_parquet(output_file, index=False)
+    else:
+        output_file = "output.csv"
+        df.to_csv(output_file, index=False)
+    
+    # Generate a preview of the top 10 rows.
+    preview = df.head(10).to_string(index=False)
+    
+    return output_file, preview
 
 demo = gr.Interface(
-    fn=convert_csv_to_parquet,
+    fn=convert_file,
     inputs=[
-        gr.File(label="CSV File"),
-        gr.Textbox(label="CSV File URL", placeholder="Enter a URL to a CSV file")
+        gr.File(label="Input File (CSV or Parquet)"),
+        gr.Textbox(label="Input File URL (optional)", placeholder="Enter a URL to a CSV or Parquet file"),
+        gr.Radio(choices=["CSV to Parquet", "Parquet to CSV"], label="Conversion Type")
+    ],
+    outputs=[
+        gr.File(label="Converted File"),
+        gr.Textbox(label="Preview (Top 10 Rows)")
     ],
-    outputs=[gr.File(label="Parquet Output")],
-    title="CSV to Parquet Converter",
-    description="Convert a CSV file to Parquet format from a downloadable link or file upload"
+    title="CSV <-> Parquet Converter",
+    description="Choose a conversion type, upload a file or enter a URL, and convert between CSV and Parquet formats. A preview of the top 10 rows will be shown."
 )
 
 if __name__ == "__main__":