Initial commit

skills/argparse-patterns/templates/choices-validation.py

@@ -0,0 +1,197 @@
+#!/usr/bin/env python3
+"""
+Argument choices and custom validation patterns.
+
+Usage:
+    python choices-validation.py --log-level debug
+    python choices-validation.py --port 8080 --host 192.168.1.1
+    python choices-validation.py --region us-east-1 --instance-type t2.micro
+"""
+
+import argparse
+import re
+import sys
+from pathlib import Path
+
+
+def validate_port(value):
+    """Custom validator for port numbers."""
+    try:
+        ivalue = int(value)
+    except ValueError:
+        raise argparse.ArgumentTypeError(f"{value} is not a valid integer")
+
+    if ivalue < 1 or ivalue > 65535:
+        raise argparse.ArgumentTypeError(
+            f"{value} is not a valid port (must be 1-65535)"
+        )
+    return ivalue
+
+
+def validate_ip(value):
+    """Custom validator for IP addresses."""
+    pattern = r'^(\d{1,3}\.){3}\d{1,3}$'
+    if not re.match(pattern, value):
+        raise argparse.ArgumentTypeError(f"{value} is not a valid IP address")
+
+    # Check each octet is 0-255
+    octets = [int(x) for x in value.split('.')]
+    if any(o < 0 or o > 255 for o in octets):
+        raise argparse.ArgumentTypeError(
+            f"{value} contains invalid octets (must be 0-255)"
+        )
+    return value
+
+
+def validate_email(value):
+    """Custom validator for email addresses."""
+    pattern = r'^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$'
+    if not re.match(pattern, value):
+        raise argparse.ArgumentTypeError(f"{value} is not a valid email address")
+    return value
+
+
+def validate_path_exists(value):
+    """Custom validator to check if path exists."""
+    path = Path(value)
+    if not path.exists():
+        raise argparse.ArgumentTypeError(f"Path does not exist: {value}")
+    return path
+
+
+def validate_range(min_val, max_val):
+    """Factory function for range validators."""
+    def validator(value):
+        try:
+            ivalue = int(value)
+        except ValueError:
+            raise argparse.ArgumentTypeError(f"{value} is not a valid integer")
+
+        if ivalue < min_val or ivalue > max_val:
+            raise argparse.ArgumentTypeError(
+                f"{value} must be between {min_val} and {max_val}"
+            )
+        return ivalue
+    return validator
+
+
+def main():
+    parser = argparse.ArgumentParser(
+        description='Demonstrate choices and validation patterns',
+        formatter_class=argparse.RawDescriptionHelpFormatter
+    )
+
+    # ===== String Choices =====
+    parser.add_argument(
+        '--log-level',
+        choices=['debug', 'info', 'warning', 'error', 'critical'],
+        default='info',
+        help='Logging level (default: %(default)s)'
+    )
+
+    parser.add_argument(
+        '--region',
+        choices=[
+            'us-east-1', 'us-west-1', 'us-west-2',
+            'eu-west-1', 'eu-central-1',
+            'ap-southeast-1', 'ap-northeast-1'
+        ],
+        default='us-east-1',
+        help='AWS region (default: %(default)s)'
+    )
+
+    parser.add_argument(
+        '--format',
+        choices=['json', 'yaml', 'toml', 'xml'],
+        default='json',
+        help='Output format (default: %(default)s)'
+    )
+
+    # ===== Custom Validators =====
+    parser.add_argument(
+        '--port',
+        type=validate_port,
+        default=8080,
+        help='Server port (1-65535, default: %(default)s)'
+    )
+
+    parser.add_argument(
+        '--host',
+        type=validate_ip,
+        default='127.0.0.1',
+        help='Server host IP (default: %(default)s)'
+    )
+
+    parser.add_argument(
+        '--email',
+        type=validate_email,
+        help='Email address for notifications'
+    )
+
+    parser.add_argument(
+        '--config',
+        type=validate_path_exists,
+        help='Path to configuration file (must exist)'
+    )
+
+    # ===== Range Validators =====
+    parser.add_argument(
+        '--workers',
+        type=validate_range(1, 32),
+        default=4,
+        help='Number of worker processes (1-32, default: %(default)s)'
+    )
+
+    parser.add_argument(
+        '--timeout',
+        type=validate_range(1, 3600),
+        default=30,
+        help='Request timeout in seconds (1-3600, default: %(default)s)'
+    )
+
+    # ===== Integer Choices =====
+    parser.add_argument(
+        '--instance-type',
+        choices=['t2.micro', 't2.small', 't2.medium', 't3.large'],
+        default='t2.micro',
+        help='EC2 instance type (default: %(default)s)'
+    )
+
+    # ===== Type Coercion =====
+    parser.add_argument(
+        '--memory',
+        type=float,
+        default=1.0,
+        help='Memory limit in GB (default: %(default)s)'
+    )
+
+    parser.add_argument(
+        '--retry-count',
+        type=int,
+        default=3,
+        help='Number of retries (default: %(default)s)'
+    )
+
+    # Parse arguments
+    args = parser.parse_args()
+
+    # Display parsed values
+    print("Configuration:")
+    print(f"  Log Level: {args.log_level}")
+    print(f"  Region: {args.region}")
+    print(f"  Format: {args.format}")
+    print(f"  Port: {args.port}")
+    print(f"  Host: {args.host}")
+    print(f"  Email: {args.email}")
+    print(f"  Config: {args.config}")
+    print(f"  Workers: {args.workers}")
+    print(f"  Timeout: {args.timeout}s")
+    print(f"  Instance Type: {args.instance_type}")
+    print(f"  Memory: {args.memory}GB")
+    print(f"  Retry Count: {args.retry_count}")
+
+    return 0
+
+
+if __name__ == '__main__':
+    sys.exit(main())