spark: add SHA256 checksum utility

wizard-work/spark/checksum.py

@@ -0,0 +1,31 @@
+#!/usr/bin/env python3
+"""File checksum utility - calculates SHA256 checksum of a file."""
+import sys
+import hashlib
+
+
+def sha256_checksum(filepath):
+    """Calculate SHA256 checksum of a file, return hex digest."""
+    sha256 = hashlib.sha256()
+    with open(filepath, 'rb') as f:
+        for chunk in iter(lambda: f.read(8192), b''):
+            sha256.update(chunk)
+    return sha256.hexdigest()
+
+
+def main():
+    if len(sys.argv) != 2:
+        print("Usage: checksum.py <filepath>")
+        sys.exit(1)
+    filepath = sys.argv[1]
+    try:
+        result = sha256_checksum(filepath)
+        print(result)
+        return 0
+    except FileNotFoundError:
+        print(f"Error: File '{filepath}' not found", file=sys.stderr)
+        return 1
+
+
+if __name__ == "__main__":
+    sys.exit(main())