refactor: Reduce code duplication in vendors/ directory

.gitignore

@@ -85,3 +85,4 @@ tmp/
 temp/
 *.tmp
 .aider*
+.serena/

core/cli/main.py

@@ -8,18 +8,22 @@
 
 
 class FinOpsCLI:
-    """Main CLI with plugin discovery."""
+    """Main CLI coordinator that discovers and manages vendor plugins.
+
+    Automatically discovers vendor plugins via setuptools entry points,
+    with fallback to direct imports for development environments.
+    """
 
     def __init__(self):
         self.vendors: Dict[str, Type[VendorCommands]] = {}
         self._discover_vendors()
 
     def _discover_vendors(self):
-        """Discover vendor plugins via entry points."""
+        """Discover vendor plugins via entry points with development fallback."""
         vendors_found = False
 
         try:
-            # Phase 2: Automatic discovery via entry points
+            # Primary method: Auto-discovery via setuptools entry points
             import pkg_resources
 
             entry_points = list(pkg_resources.iter_entry_points('open_finops.vendors'))
@@ -34,21 +38,24 @@ def _discover_vendors(self):
                     print(f"⚠ Failed to load vendor plugin {entry_point.name}: {e}")
 
         except ImportError:
-            pass  # pkg_resources not available
+            # pkg_resources not available (rare case)
+            pass
 
-        # Fallback: Manual discovery for development mode
+        # Development fallback: Direct import when entry points not set up
         if not vendors_found:
             try:
                 from vendors.aws.cli import AWSCommands
                 self.vendors['aws'] = AWSCommands
             except ImportError:
-                pass  # AWS not installed
+                # AWS vendor not available in this installation
+                pass
 
     def run(self):
-        """Run the CLI."""
+        """Parse arguments and execute the appropriate vendor command."""
         parser = self._create_parser()
         args = parser.parse_args()
 
+        # Show help if no command specified
         if not args.command:
             parser.print_help()
             sys.exit(0)
@@ -59,8 +66,12 @@ def run(self):
             vendor_instance = vendor_class()
             vendor_instance.execute(args)
         else:
+            # Handle unknown vendor with helpful error message
             print(f"Vendor '{args.command}' not available")
-            print(f"Available vendors: {', '.join(self.vendors.keys())}")
+            if self.vendors:
+                print(f"Available vendors: {', '.join(self.vendors.keys())}")
+            else:
+                print("No vendor plugins found. Check your installation.")
             sys.exit(1)
 
     def _create_parser(self):
@@ -75,7 +86,7 @@ def _create_parser(self):
 
         subparsers = parser.add_subparsers(dest='command', help='Available commands')
 
-        # Let each vendor add its subcommands
+        # Register subcommands from each discovered vendor plugin
         for name, vendor_class in self.vendors.items():
             vendor_instance = vendor_class()
             vendor_instance.add_subparser(subparsers)

vendors/aws/cli.py

@@ -11,47 +11,59 @@
 from .manifest import ManifestLocator
 
 
-def aws_import_cur(args):
-    """Import AWS Cost and Usage Reports."""
-
-    # Load configuration
+def _load_and_validate_config(args, required_aws_fields=True):
+    """Load configuration, merge CLI args, and validate AWS config if needed."""
     config_path = Path(args.config) if args.config else Path('config.toml')
     config = Config.load(config_path)
 
-    # Merge CLI arguments into configuration
+    # Merge CLI arguments into configuration (only non-None values)
     cli_args = {
-        'bucket': args.bucket,
-        'prefix': args.prefix,
-        'export_name': args.export_name,
-        'cur_version': args.cur_version,
-        'export_format': args.export_format,
-        'start_date': args.start_date,
-        'end_date': args.end_date,
-        'reset': args.reset,
-        'table_strategy': args.table_strategy
+        'bucket': getattr(args, 'bucket', None),
+        'prefix': getattr(args, 'prefix', None),
+        'export_name': getattr(args, 'export_name', None),
+        'cur_version': getattr(args, 'cur_version', None),
+        'export_format': getattr(args, 'export_format', None),
+        'start_date': getattr(args, 'start_date', None),
+        'end_date': getattr(args, 'end_date', None),
+        'reset': getattr(args, 'reset', None),
+        'table_strategy': getattr(args, 'table_strategy', None)
     }
+    cli_args = {k: v for k, v in cli_args.items() if v is not None}
+    config.merge_cli_args(cli_args)
 
     # Override database backend if specified via CLI
     if hasattr(args, 'destination') and args.destination != 'duckdb':
-        # CLI override for destination
         config.database.backend = args.destination
 
-    # Remove None values
-    cli_args = {k: v for k, v in cli_args.items() if v is not None}
-
-    # Merge with config
-    config.merge_cli_args(cli_args)
+    # Validate AWS configuration if required
+    if required_aws_fields:
+        try:
+            config.validate_aws_config()
+        except ValueError as e:
+            print(f"Error: {e}", file=sys.stderr)
+            print("\nRequired parameters can be set via:")
+            print("  - config.toml file")
+            print("  - Environment variables (OPEN_FINOPS_AWS_*)")
+            print("  - Command-line flags")
+            sys.exit(1)
+
+    return config
+
+
+def _get_aws_credentials(config):
+    """Extract AWS credentials dictionary from config."""
+    return {
+        'access_key_id': config.aws.access_key_id,
+        'secret_access_key': config.aws.secret_access_key,
+        'region': config.aws.region
+    }
+
+
+def aws_import_cur(args):
+    """Import AWS Cost and Usage Reports."""
 
-    # Validate we have required fields
-    try:
-        config.validate_aws_config()
-    except ValueError as e:
-        print(f"Error: {e}", file=sys.stderr)
-        print("\nRequired parameters can be set via:")
-        print("  - config.toml file")
-        print("  - Environment variables (OPEN_FINOPS_AWS_*)")
-        print("  - Command-line flags")
-        sys.exit(1)
+    # Load and validate configuration
+    config = _load_and_validate_config(args)
 
     # Show configuration
     print("\nAWS CUR Import Configuration:")
@@ -87,33 +99,11 @@ def aws_import_cur(args):
 def aws_list_manifests(args):
     """List available billing periods in S3."""
 
-    # Load configuration
-    config_path = Path(args.config) if args.config else Path('config.toml')
-    config = Config.load(config_path)
-
-    # Merge CLI arguments for bucket/prefix/export_name if provided
-    cli_args = {
-        'bucket': args.bucket,
-        'prefix': args.prefix,
-        'export_name': args.export_name,
-        'cur_version': args.cur_version
-    }
-    cli_args = {k: v for k, v in cli_args.items() if v is not None}
-    config.merge_cli_args(cli_args)
-
-    # Validate we have required fields
-    try:
-        config.validate_aws_config()
-    except ValueError as e:
-        print(f"Error: {e}", file=sys.stderr)
-        sys.exit(1)
+    # Load and validate configuration
+    config = _load_and_validate_config(args)
 
     # Get AWS credentials
-    aws_creds = {
-        'access_key_id': config.aws.access_key_id,
-        'secret_access_key': config.aws.secret_access_key,
-        'region': config.aws.region
-    }
+    aws_creds = _get_aws_credentials(config)
 
     # Initialize manifest locator
     locator = ManifestLocator(
@@ -148,9 +138,8 @@ def aws_list_manifests(args):
 def aws_show_state(args):
     """Show load state and version history."""
 
-    # Load configuration
-    config_path = Path(args.config) if args.config else Path('config.toml')
-    config = Config.load(config_path)
+    # Load configuration (don't require all AWS fields, just export_name)
+    config = _load_and_validate_config(args, required_aws_fields=False)
 
     # Override export name if provided
     if args.export_name:
@@ -229,9 +218,8 @@ def aws_show_state(args):
 def aws_list_exports(args):
     """List all available exports and their tables."""
 
-    # Load configuration
-    config_path = Path(args.config) if args.config else Path('config.toml')
-    config = Config.load(config_path)
+    # Load configuration (don't require AWS fields for this command)
+    config = _load_and_validate_config(args, required_aws_fields=False)
 
     # Set up data directory path
     if config.project and config.project.data_dir: