feat: trying a license checker (#184)

.github/workflows/scripts/check_licenses.py

@@ -0,0 +1,174 @@
+#!/usr/bin/env python3
+
+from pathlib import Path
+import tomli
+import sys
+import requests
+import urllib3
+from typing import Dict, List, Optional, Set
+
+# Define allowed licenses and exceptions directly in the script
+ALLOWED_LICENSES = {
+    "MIT",
+    "BSD-3-Clause",
+    "Apache-2.0",
+    "Apache Software License",
+    "Python Software Foundation License",
+    "BSD License",
+    "ISC"
+}
+
+# Package-specific exceptions
+EXCEPTIONS = {
+    "ai-exchange": True,  # Local workspace package
+    "tiktoken": True,     # Known MIT license with non-standard format
+}
+
+class LicenseChecker:
+    def __init__(self):
+        self.session = requests.Session()
+        # Configure session for robust SSL handling
+        self.session.verify = True
+        adapter = requests.adapters.HTTPAdapter(
+            max_retries=urllib3.util.Retry(
+                total=3,
+                backoff_factor=0.5,
+                status_forcelist=[500, 502, 503, 504]
+            )
+        )
+        self.session.mount('https://', adapter)
+        
+    def normalize_license(self, license_str: Optional[str]) -> Optional[str]:
+        """Normalize license string for comparison."""
+        if not license_str:
+            return None
+        
+        # Convert to uppercase and remove common words and punctuation
+        normalized = license_str.upper().replace(' LICENSE', '').replace(' LICENCE', '').strip()
+        
+        # Common substitutions
+        replacements = {
+            'APACHE 2.0': 'APACHE-2.0',
+            'APACHE SOFTWARE LICENSE': 'APACHE-2.0',
+            'BSD': 'BSD-3-CLAUSE',
+            'MIT LICENSE': 'MIT',
+            'PYTHON SOFTWARE FOUNDATION': 'PSF',
+        }
+        
+        return replacements.get(normalized, normalized)
+    
+    def get_package_license(self, package_name: str) -> Optional[str]:
+        """Fetch license information from PyPI."""
+        if package_name in EXCEPTIONS:
+            return "APPROVED-EXCEPTION"
+
+        try:
+            response = self.session.get(f"https://pypi.org/pypi/{package_name}/json")
+            response.raise_for_status()
+            data = response.json()
+            
+            license_info = (
+                data['info'].get('license') or
+                data['info'].get('classifiers', [])
+            )
+            
+            if isinstance(license_info, list):
+                for classifier in license_info:
+                    if classifier.startswith('License :: '):
+                        parts = classifier.split(' :: ')
+                        return parts[-1]
+            
+            return license_info if isinstance(license_info, str) else None
+        
+        except requests.exceptions.SSLError as e:
+            print(f"SSL Error fetching license for {package_name}: {e}", file=sys.stderr)
+            return None
+        except Exception as e:
+            print(f"Warning: Could not fetch license for {package_name}: {e}", file=sys.stderr)
+            return None
+
+    def extract_dependencies(self, toml_file: Path) -> List[str]:
+        """Extract all dependencies from a TOML file."""
+        with open(toml_file, 'rb') as f:
+            data = tomli.load(f)
+        
+        dependencies = []
+        
+        # Get direct dependencies
+        project_deps = data.get('project', {}).get('dependencies', [])
+        dependencies.extend(self._parse_dependency_strings(project_deps))
+        
+        # Get dev dependencies
+        tool_deps = data.get('tool', {}).get('uv', {}).get('dev-dependencies', [])
+        dependencies.extend(self._parse_dependency_strings(tool_deps))
+        
+        return list(set(dependencies))
+    
+    def _parse_dependency_strings(self, deps: List[str]) -> List[str]:
+        """Parse dependency strings to extract package names."""
+        packages = []
+        for dep in deps:
+            # Skip workspace references
+            if dep.endswith('workspace = true}'):
+                continue
+            
+            # Handle basic package specifiers
+            package = dep.split('>=')[0].split('==')[0].split('<')[0].split('>')[0].strip()
+            package = package.split('{')[0].strip()
+            packages.append(package)
+        return packages
+    
+    def check_licenses(self, toml_file: Path) -> Dict[str, Dict[str, bool]]:
+        """Check licenses for all dependencies in the TOML file."""
+        dependencies = self.extract_dependencies(toml_file)
+        results = {}
+        checked = set()
+        
+        for package in dependencies:
+            if package in checked:
+                continue
+                
+            checked.add(package)
+            
+            if package in EXCEPTIONS:
+                results[package] = {
+                    'license': 'Approved Exception',
+                    'allowed': True
+                }
+                continue
+                
+            license_info = self.get_package_license(package)
+            normalized_license = self.normalize_license(license_info)
+            allowed = False
+            
+            if normalized_license:
+                allowed = (normalized_license in {self.normalize_license(l) for l in ALLOWED_LICENSES} or
+                          package in EXCEPTIONS)
+            
+            results[package] = {
+                'license': license_info,
+                'allowed': allowed
+            }
+        
+        return results
+
+def main():
+    if len(sys.argv) < 2:
+        print("Usage: check_licenses.py <toml_file>", file=sys.stderr)
+        sys.exit(1)
+    
+    toml_file = Path(sys.argv[1])
+    checker = LicenseChecker()
+    results = checker.check_licenses(toml_file)
+    
+    any_disallowed = False
+    for package, info in sorted(results.items()):
+        status = "✓" if info['allowed'] else "✗"
+        print(f"{status} {package}: {info['license']}")
+        if not info['allowed']:
+            any_disallowed = True
+    
+    sys.exit(1 if any_disallowed else 0)
+
+if __name__ == '__main__':
+    main()