excel-heredoc-fallback

Excel Creation via Shell Heredoc Fallback

Overview

When creating Excel files with openpyxl, execute_code_sandbox may fail due to sandbox restrictions, missing dependencies, or permission issues. This skill provides a reliable fallback: execute Python code via run_shell using an inline heredoc script. This approach often succeeds where the sandbox fails and supports full openpyxl features including styling, formulas, and formatting.

When to Use This Skill

• execute_code_sandbox fails when importing or using openpyxl
• Sandbox shows errors about missing packages, permissions, or execution restrictions
• You need to create Excel files with advanced formatting (styles, colors, merged cells, formulas)
• Previous sandbox attempts have failed multiple times

Step-by-Step Instructions

Step 1: Attempt Sandbox Execution First

Always try execute_code_sandbox first, as it's cleaner and preferred when it works:

from openpyxl import Workbook
from openpyxl.styles import Font, Fill, PatternFill, Alignment

wb = Workbook()
ws = wb.active
ws['A1'] = 'Header'
ws['A1'].font = Font(bold=True)
wb.save('output.xlsx')

Step 2: Detect Sandbox Failure

Watch for these failure indicators:

• ImportError for openpyxl or related modules
• Permission denied errors
• File write failures
• Repeated retry loops without success
• Timeout or resource errors

Step 3: Fall Back to Shell Heredoc

When sandbox fails, switch to run_shell with a Python heredoc:

python3 << 'EOF'
from openpyxl import Workbook
from openpyxl.styles import Font, Fill, PatternFill, Alignment, Border, Side

# Create workbook
wb = Workbook()
ws = wb.active
ws.title = "Sheet1"

# Add data with formatting
ws['A1'] = 'Name'
ws['B1'] = 'Value'
ws['A1'].font = Font(bold=True, size=14)
ws['B1'].font = Font(bold=True, size=14)

# Add rows
data = [
    ['Item 1', 100],
    ['Item 2', 200],
    ['Item 3', 150],
]

for row_idx, row_data in enumerate(data, start=2):
    for col_idx, value in enumerate(row_data, start=1):
        cell = ws.cell(row=row_idx, column=col_idx, value=value)
        cell.alignment = Alignment(horizontal='center')

# Add formulas if needed
ws['B5'] = '=SUM(B2:B4)'

# Save the file
wb.save('output.xlsx')
print("Excel file created successfully: output.xlsx")
EOF