app/__init__.py

@@ -45,7 +45,6 @@ def _migrate_config_file(active_path: Path, legacy_paths: List[Path]) -> Path:
             try:
                 shutil.move(str(legacy_path), str(active_path))
             except OSError:
-                # Fall back to copy + delete for cross-device moves
                 shutil.copy2(legacy_path, active_path)
                 try:
                     legacy_path.unlink(missing_ok=True)
@@ -101,12 +100,10 @@ def create_app(
     bucket_policies = BucketPolicyStore(Path(app.config["BUCKET_POLICY_PATH"]))
     secret_store = EphemeralSecretStore(default_ttl=app.config.get("SECRET_TTL_SECONDS", 300))
     
-    # Initialize replication with system config directory for consistency
     storage_root = Path(app.config["STORAGE_ROOT"])
     config_dir = storage_root / ".myfsio.sys" / "config"
     config_dir.mkdir(parents=True, exist_ok=True)
     
-    # Migrate connection configs from legacy locations
     connections_path = _migrate_config_file(
         active_path=config_dir / "connections.json",
         legacy_paths=[
@@ -125,7 +122,6 @@ def create_app(
     connections = ConnectionStore(connections_path)
     replication = ReplicationManager(storage, connections, replication_rules_path)
     
-    # Initialize encryption and KMS
     encryption_config = {
         "encryption_enabled": app.config.get("ENCRYPTION_ENABLED", False),
         "encryption_master_key_path": app.config.get("ENCRYPTION_MASTER_KEY_PATH"),
@@ -140,7 +136,6 @@ def create_app(
         kms_manager = KMSManager(kms_keys_path, kms_master_key_path)
         encryption_manager.set_kms_provider(kms_manager)
 
-    # Wrap storage with encryption layer if encryption is enabled
     if app.config.get("ENCRYPTION_ENABLED", False):
         from .encrypted_storage import EncryptedObjectStorage
         storage = EncryptedObjectStorage(storage, encryption_manager)
@@ -243,7 +238,7 @@ def _configure_cors(app: Flask) -> None:
 class _RequestContextFilter(logging.Filter):
     """Inject request-specific attributes into log records."""
 
-    def filter(self, record: logging.LogRecord) -> bool:  # pragma: no cover - simple boilerplate
+    def filter(self, record: logging.LogRecord) -> bool:  
         if has_request_context():
             record.request_id = getattr(g, "request_id", "-")
             record.path = request.path

app/bucket_policies.py

@@ -188,7 +188,6 @@ class BucketPolicyStore:
         except FileNotFoundError:
             return None
 
-    # ------------------------------------------------------------------
     def evaluate(
         self,
         access_key: Optional[str],
@@ -229,7 +228,6 @@ class BucketPolicyStore:
         self._policies.pop(bucket, None)
         self._persist()
 
-    # ------------------------------------------------------------------
     def _load(self) -> None:
         try:
             content = self.policy_path.read_text(encoding='utf-8')

app/config.py

@@ -153,9 +153,8 @@ class AppConfig:
         cors_allow_headers = _csv(str(_get("CORS_ALLOW_HEADERS", "*")), ["*"])
         cors_expose_headers = _csv(str(_get("CORS_EXPOSE_HEADERS", "*")), ["*"])
         session_lifetime_days = int(_get("SESSION_LIFETIME_DAYS", 30))
-        bucket_stats_cache_ttl = int(_get("BUCKET_STATS_CACHE_TTL", 60))  # Default 60 seconds
+        bucket_stats_cache_ttl = int(_get("BUCKET_STATS_CACHE_TTL", 60)) 
         
-        # Encryption settings
         encryption_enabled = str(_get("ENCRYPTION_ENABLED", "0")).lower() in {"1", "true", "yes", "on"}
         encryption_keys_dir = storage_root / ".myfsio.sys" / "keys"
         encryption_master_key_path = Path(_get("ENCRYPTION_MASTER_KEY_PATH", encryption_keys_dir / "master.key")).resolve()
@@ -206,7 +205,6 @@ class AppConfig:
         """
         issues = []
         
-        # Check if storage_root is writable
         try:
             test_file = self.storage_root / ".write_test"
             test_file.touch()
@@ -214,24 +212,20 @@ class AppConfig:
         except (OSError, PermissionError) as e:
             issues.append(f"CRITICAL: STORAGE_ROOT '{self.storage_root}' is not writable: {e}")
         
-        # Check if storage_root looks like a temp directory
         storage_str = str(self.storage_root).lower()
         if "/tmp" in storage_str or "\\temp" in storage_str or "appdata\\local\\temp" in storage_str:
             issues.append(f"WARNING: STORAGE_ROOT '{self.storage_root}' appears to be a temporary directory. Data may be lost on reboot!")
         
-        # Check if IAM config path is under storage_root
         try:
             self.iam_config_path.relative_to(self.storage_root)
         except ValueError:
             issues.append(f"WARNING: IAM_CONFIG '{self.iam_config_path}' is outside STORAGE_ROOT '{self.storage_root}'. Consider setting IAM_CONFIG explicitly or ensuring paths are aligned.")
         
-        # Check if bucket policy path is under storage_root
         try:
             self.bucket_policy_path.relative_to(self.storage_root)
         except ValueError:
             issues.append(f"WARNING: BUCKET_POLICY_PATH '{self.bucket_policy_path}' is outside STORAGE_ROOT '{self.storage_root}'. Consider setting BUCKET_POLICY_PATH explicitly.")
         
-        # Check if log path is writable
         try:
             self.log_path.parent.mkdir(parents=True, exist_ok=True)
             test_log = self.log_path.parent / ".write_test"
@@ -240,26 +234,22 @@ class AppConfig:
         except (OSError, PermissionError) as e:
             issues.append(f"WARNING: Log directory '{self.log_path.parent}' is not writable: {e}")
         
-        # Check log path location
         log_str = str(self.log_path).lower()
         if "/tmp" in log_str or "\\temp" in log_str or "appdata\\local\\temp" in log_str:
             issues.append(f"WARNING: LOG_DIR '{self.log_path.parent}' appears to be a temporary directory. Logs may be lost on reboot!")
         
-        # Check if encryption keys path is under storage_root (when encryption is enabled)
         if self.encryption_enabled:
             try:
                 self.encryption_master_key_path.relative_to(self.storage_root)
             except ValueError:
                 issues.append(f"WARNING: ENCRYPTION_MASTER_KEY_PATH '{self.encryption_master_key_path}' is outside STORAGE_ROOT. Ensure proper backup procedures.")
         
-        # Check if KMS keys path is under storage_root (when KMS is enabled)
         if self.kms_enabled:
             try:
                 self.kms_keys_path.relative_to(self.storage_root)
             except ValueError:
                 issues.append(f"WARNING: KMS_KEYS_PATH '{self.kms_keys_path}' is outside STORAGE_ROOT. Ensure proper backup procedures.")
         
-        # Warn about production settings
         if self.secret_key == "dev-secret-key":
             issues.append("WARNING: Using default SECRET_KEY. Set SECRET_KEY environment variable for production.")
         

app/iam.py

@@ -125,7 +125,6 @@ class IamService:
         except OSError:
             pass
 
-    # ---------------------- authz helpers ----------------------
     def authenticate(self, access_key: str, secret_key: str) -> Principal:
         self._maybe_reload()
         access_key = (access_key or "").strip()
@@ -218,7 +217,6 @@ class IamService:
                 return True
         return False
 
-    # ---------------------- management helpers ----------------------
     def list_users(self) -> List[Dict[str, Any]]:
         listing: List[Dict[str, Any]] = []
         for access_key, record in self._users.items():
@@ -291,7 +289,6 @@ class IamService:
         self._save()
         self._load()
 
-    # ---------------------- config helpers ----------------------
     def _load(self) -> None:
         try:
             self._last_load_time = self.config_path.stat().st_mtime
@@ -337,7 +334,6 @@ class IamService:
         except (OSError, PermissionError) as e:
             raise IamError(f"Cannot save IAM config: {e}")
 
-    # ---------------------- insight helpers ----------------------
     def config_summary(self) -> Dict[str, Any]:
         return {
             "path": str(self.config_path),

app/kms_api.py

@@ -33,9 +33,6 @@ def _encryption():
 def _error_response(code: str, message: str, status: int) -> tuple[Dict[str, Any], int]:
     return {"__type": code, "message": message}, status
 
-
-# ---------------------- Key Management ----------------------
-
 @kms_api_bp.route("/keys", methods=["GET", "POST"])
 @limiter.limit("30 per minute")
 def list_or_create_keys():
@@ -65,7 +62,6 @@ def list_or_create_keys():
         except EncryptionError as exc:
             return _error_response("KMSInternalException", str(exc), 400)
     
-    # GET - List keys
     keys = kms.list_keys()
     return jsonify({
         "Keys": [{"KeyId": k.key_id, "KeyArn": k.arn} for k in keys],
@@ -96,7 +92,6 @@ def get_or_delete_key(key_id: str):
         except EncryptionError as exc:
             return _error_response("NotFoundException", str(exc), 404)
     
-    # GET
     key = kms.get_key(key_id)
     if not key:
         return _error_response("NotFoundException", f"Key not found: {key_id}", 404)
@@ -149,9 +144,6 @@ def disable_key(key_id: str):
     except EncryptionError as exc:
         return _error_response("NotFoundException", str(exc), 404)
 
-
-# ---------------------- Encryption Operations ----------------------
-
 @kms_api_bp.route("/encrypt", methods=["POST"])
 @limiter.limit("60 per minute")
 def encrypt_data():
@@ -251,7 +243,6 @@ def generate_data_key():
     try:
         plaintext_key, encrypted_key = kms.generate_data_key(key_id, context)
         
-        # Trim key if AES_128 requested
         if key_spec == "AES_128":
             plaintext_key = plaintext_key[:16]
         
@@ -322,10 +313,7 @@ def re_encrypt():
         return _error_response("ValidationException", "CiphertextBlob must be base64 encoded", 400)
     
     try:
-        # First decrypt, get source key id
         plaintext, source_key_id = kms.decrypt(ciphertext, source_context)
-        
-        # Re-encrypt with destination key
         new_ciphertext = kms.encrypt(destination_key_id, plaintext, destination_context)
         
         return jsonify({
@@ -365,9 +353,6 @@ def generate_random():
     except EncryptionError as exc:
         return _error_response("ValidationException", str(exc), 400)
 
-
-# ---------------------- Client-Side Encryption Helpers ----------------------
-
 @kms_api_bp.route("/client/generate-key", methods=["POST"])
 @limiter.limit("30 per minute")
 def generate_client_key():
@@ -427,9 +412,6 @@ def client_decrypt():
     except Exception as exc:
         return _error_response("DecryptionError", str(exc), 400)
 
-
-# ---------------------- Encryption Materials for S3 Client-Side Encryption ----------------------
-
 @kms_api_bp.route("/materials/<key_id>", methods=["POST"])
 @limiter.limit("60 per minute")
 def get_encryption_materials(key_id: str):

app/replication.py

@@ -22,6 +22,8 @@ from .storage import ObjectStorage, StorageError
 logger = logging.getLogger(__name__)
 
 REPLICATION_USER_AGENT = "S3ReplicationAgent/1.0"
+REPLICATION_CONNECT_TIMEOUT = 5  # seconds to wait for connection
+REPLICATION_READ_TIMEOUT = 30   # seconds to wait for response
 
 REPLICATION_MODE_NEW_ONLY = "new_only"
 REPLICATION_MODE_ALL = "all"
@@ -121,6 +123,34 @@ class ReplicationManager:
         with open(self.rules_path, "w") as f:
             json.dump(data, f, indent=2)
 
+    def check_endpoint_health(self, connection: RemoteConnection) -> bool:
+        """Check if a remote endpoint is reachable and responsive.
+        
+        Returns True if endpoint is healthy, False otherwise.
+        Uses short timeouts to prevent blocking.
+        """
+        try:
+            config = Config(
+                user_agent_extra=REPLICATION_USER_AGENT,
+                connect_timeout=REPLICATION_CONNECT_TIMEOUT,
+                read_timeout=REPLICATION_READ_TIMEOUT,
+                retries={'max_attempts': 1}  # Don't retry for health checks
+            )
+            s3 = boto3.client(
+                "s3",
+                endpoint_url=connection.endpoint_url,
+                aws_access_key_id=connection.access_key,
+                aws_secret_access_key=connection.secret_key,
+                region_name=connection.region,
+                config=config,
+            )
+            # Simple list_buckets call to verify connectivity
+            s3.list_buckets()
+            return True
+        except Exception as e:
+            logger.warning(f"Endpoint health check failed for {connection.name} ({connection.endpoint_url}): {e}")
+            return False
+
     def get_rule(self, bucket_name: str) -> Optional[ReplicationRule]:
         return self._rules.get(bucket_name)
 
@@ -218,6 +248,11 @@ class ReplicationManager:
             logger.warning(f"Cannot replicate existing objects: Connection {rule.target_connection_id} not found")
             return
         
+        # Check endpoint health before starting bulk replication
+        if not self.check_endpoint_health(connection):
+            logger.warning(f"Cannot replicate existing objects: Endpoint {connection.name} ({connection.endpoint_url}) is not reachable")
+            return
+        
         try:
             objects = self.storage.list_objects_all(bucket_name)
             logger.info(f"Starting replication of {len(objects)} existing objects from {bucket_name}")
@@ -255,6 +290,11 @@ class ReplicationManager:
             logger.warning(f"Replication skipped for {bucket_name}/{object_key}: Connection {rule.target_connection_id} not found")
             return
 
+        # Check endpoint health before attempting replication to prevent hangs
+        if not self.check_endpoint_health(connection):
+            logger.warning(f"Replication skipped for {bucket_name}/{object_key}: Endpoint {connection.name} ({connection.endpoint_url}) is not reachable")
+            return
+
         self._executor.submit(self._replicate_task, bucket_name, object_key, rule, connection, action)
 
     def _replicate_task(self, bucket_name: str, object_key: str, rule: ReplicationRule, conn: RemoteConnection, action: str) -> None:
@@ -271,13 +311,20 @@ class ReplicationManager:
         
         file_size = 0
         try:
-            config = Config(user_agent_extra=REPLICATION_USER_AGENT)
+            config = Config(
+                user_agent_extra=REPLICATION_USER_AGENT,
+                connect_timeout=REPLICATION_CONNECT_TIMEOUT,
+                read_timeout=REPLICATION_READ_TIMEOUT,
+                retries={'max_attempts': 2},  # Limited retries to prevent long hangs
+                signature_version='s3v4',  # Force signature v4 for compatibility
+                s3={'addressing_style': 'path'}  # Use path-style addressing for compatibility
+            )
             s3 = boto3.client(
                 "s3",
                 endpoint_url=conn.endpoint_url,
                 aws_access_key_id=conn.access_key,
                 aws_secret_access_key=conn.secret_key,
-                region_name=conn.region,
+                region_name=conn.region or 'us-east-1',  # Default region if not set
                 config=config,
             )
 
@@ -309,16 +356,31 @@ class ReplicationManager:
             logger.info(f"Replicating {bucket_name}/{object_key}: Size={file_size}, ContentType={content_type}")
 
             def do_put_object() -> None:
-                """Helper to upload object."""
+                """Helper to upload object.
-                with path.open("rb") as f:
+                
-                    s3.put_object(
+                Reads the file content into memory first to avoid signature calculation
-                        Bucket=rule.target_bucket,
+                issues with certain binary file types (like GIFs) when streaming.
-                        Key=object_key,
+                Do NOT set ContentLength explicitly - boto3 calculates it from the bytes
-                        Body=f,
+                and setting it manually can cause SignatureDoesNotMatch errors.
-                        ContentLength=file_size,
+                """
-                        ContentType=content_type or "application/octet-stream",
+                file_content = path.read_bytes()
-                        Metadata=metadata or {}
+                put_kwargs = {
-                    )
+                    "Bucket": rule.target_bucket,
+                    "Key": object_key,
+                    "Body": file_content,
+                }
+                if content_type:
+                    put_kwargs["ContentType"] = content_type
+                if metadata:
+                    put_kwargs["Metadata"] = metadata
+                
+                # Debug logging for signature issues
+                logger.debug(f"PUT request details: bucket={rule.target_bucket}, key={repr(object_key)}, "
+                            f"content_type={content_type}, body_len={len(file_content)}, "
+                            f"endpoint={conn.endpoint_url}")
+                logger.debug(f"Key bytes: {object_key.encode('utf-8')}")
+                
+                s3.put_object(**put_kwargs)
 
             try:
                 do_put_object()
@@ -358,6 +420,14 @@ class ReplicationManager:
 
         except (ClientError, OSError, ValueError) as e:
             logger.error(f"Replication failed for {bucket_name}/{object_key}: {e}")
+            # Log additional debug info for signature errors
+            if isinstance(e, ClientError):
+                error_code = e.response.get('Error', {}).get('Code', '')
+                if 'Signature' in str(e) or 'Signature' in error_code:
+                    logger.error(f"Signature debug - Key repr: {repr(object_key)}, "
+                                f"Endpoint: {conn.endpoint_url}, "
+                                f"Region: {conn.region}, "
+                                f"Target bucket: {rule.target_bucket}")
         except Exception:
             logger.exception(f"Unexpected error during replication for {bucket_name}/{object_key}")
 

app/s3_api.py

@@ -8,7 +8,7 @@ import re
 import uuid
 from datetime import datetime, timedelta, timezone
 from typing import Any, Dict
-from urllib.parse import quote, urlencode, urlparse
+from urllib.parse import quote, urlencode, urlparse, unquote
 from xml.etree.ElementTree import Element, SubElement, tostring, fromstring, ParseError
 
 from flask import Blueprint, Response, current_app, jsonify, request, g
@@ -22,8 +22,6 @@ from .storage import ObjectStorage, StorageError, QuotaExceededError
 
 s3_api_bp = Blueprint("s3_api", __name__)
 
-
-# Helper functions for accessing app extensions and generating responses
 def _storage() -> ObjectStorage:
     return current_app.extensions["object_storage"]
 
@@ -68,8 +66,26 @@ def _get_signature_key(key: str, date_stamp: str, region_name: str, service_name
     return k_signing
 
 
+def _get_canonical_uri(req: Any) -> str:
+    """Get the canonical URI for SigV4 signature verification.
+    
+    AWS SigV4 requires the canonical URI to be URL-encoded exactly as the client
+    sent it. Flask/Werkzeug automatically URL-decodes request.path, so we need
+    to get the raw path from the environ.
+    
+    The canonical URI should have each path segment URL-encoded (with '/' preserved),
+    and the encoding should match what the client used when signing.
+    """
+    raw_uri = req.environ.get('RAW_URI') or req.environ.get('REQUEST_URI')
+    
+    if raw_uri:
+        path = raw_uri.split('?')[0]
+        return path
+    
+    return quote(req.path, safe="/-_.~")
+
+
 def _verify_sigv4_header(req: Any, auth_header: str) -> Principal | None:
-    # Parse Authorization header: AWS4-HMAC-SHA256 Credential=AKIA.../20230101/us-east-1/s3/aws4_request, SignedHeaders=host;x-amz-date, Signature=...
     match = re.match(
         r"AWS4-HMAC-SHA256 Credential=([^/]+)/([^/]+)/([^/]+)/([^/]+)/aws4_request, SignedHeaders=([^,]+), Signature=(.+)",
         auth_header,
@@ -82,9 +98,8 @@ def _verify_sigv4_header(req: Any, auth_header: str) -> Principal | None:
     if not secret_key:
         raise IamError("Invalid access key")
 
-    # Build canonical request
     method = req.method
-    canonical_uri = quote(req.path, safe="/-_.~")
+    canonical_uri = _get_canonical_uri(req)
     
     query_args = []
     for key, value in req.args.items(multi=True):
@@ -124,13 +139,12 @@ def _verify_sigv4_header(req: Any, auth_header: str) -> Principal | None:
 
     now = datetime.now(timezone.utc)
     time_diff = abs((now - request_time).total_seconds())
-    if time_diff > 900:  # AWS standard: 15-minute request validity window
+    if time_diff > 900:
         raise IamError("Request timestamp too old or too far in the future")
 
     required_headers = {'host', 'x-amz-date'}
     signed_headers_set = set(signed_headers_str.split(';'))
     if not required_headers.issubset(signed_headers_set):
-        # Some clients use 'date' instead of 'x-amz-date'
         if 'date' in signed_headers_set:
             required_headers.remove('x-amz-date')
             required_headers.add('date')
@@ -177,9 +191,8 @@ def _verify_sigv4_query(req: Any) -> Principal | None:
     if not secret_key:
         raise IamError("Invalid access key")
 
-    # Build canonical request
     method = req.method
-    canonical_uri = quote(req.path, safe="/-_.~")
+    canonical_uri = _get_canonical_uri(req)
     
     query_args = []
     for key, value in req.args.items(multi=True):
@@ -211,7 +224,6 @@ def _verify_sigv4_query(req: Any) -> Principal | None:
         payload_hash
     ])
     
-    # Build signature
     algorithm = "AWS4-HMAC-SHA256"
     credential_scope = f"{date_stamp}/{region}/{service}/aws4_request"
     hashed_request = hashlib.sha256(canonical_request.encode('utf-8')).hexdigest()
@@ -479,7 +491,6 @@ def _generate_presigned_url(
     }
     canonical_query = _encode_query_params(query_params)
 
-    # Get presigned URL host and scheme from config or request headers
     api_base = current_app.config.get("API_BASE_URL")
     if api_base:
         parsed = urlparse(api_base)
@@ -839,7 +850,6 @@ def _bucket_versioning_handler(bucket_name: str) -> Response:
         current_app.logger.info("Bucket versioning updated", extra={"bucket": bucket_name, "status": status})
         return Response(status=200)
     
-    # GET
     try:
         enabled = storage.is_versioning_enabled(bucket_name)
     except StorageError as exc:
@@ -875,7 +885,7 @@ def _bucket_tagging_handler(bucket_name: str) -> Response:
             return _error_response("NoSuchBucket", str(exc), 404)
         current_app.logger.info("Bucket tags deleted", extra={"bucket": bucket_name})
         return Response(status=204)
-    # PUT
+
     payload = request.get_data(cache=False) or b""
     try:
         tags = _parse_tagging_document(payload)
@@ -900,7 +910,6 @@ def _object_tagging_handler(bucket_name: str, object_key: str) -> Response:
     if error:
         return error
     
-    # Use read permission for GET, write for PUT/DELETE
     action = "read" if request.method == "GET" else "write"
     try:
         _authorize_action(principal, bucket_name, action, object_key=object_key)
@@ -1079,7 +1088,6 @@ def _bucket_location_handler(bucket_name: str) -> Response:
     if not storage.bucket_exists(bucket_name):
         return _error_response("NoSuchBucket", "Bucket does not exist", 404)
     
-    # Return bucket location (empty for us-east-1 per AWS spec)
     region = current_app.config.get("AWS_REGION", "us-east-1")
     root = Element("LocationConstraint")
     root.text = region if region != "us-east-1" else None
@@ -1106,7 +1114,6 @@ def _bucket_acl_handler(bucket_name: str) -> Response:
         current_app.logger.info("Bucket ACL set (canned)", extra={"bucket": bucket_name, "acl": canned_acl})
         return Response(status=200)
     
-    # Return basic ACL document showing owner's full control
     root = Element("AccessControlPolicy")
     owner = SubElement(root, "Owner")
     SubElement(owner, "ID").text = principal.access_key if principal else "anonymous"
@@ -1154,7 +1161,6 @@ def _bucket_list_versions_handler(bucket_name: str) -> Response:
     if key_marker:
         objects = [obj for obj in objects if obj.key > key_marker]
     
-    # Build XML response
     root = Element("ListVersionsResult", xmlns="http://s3.amazonaws.com/doc/2006-03-01/")
     SubElement(root, "Name").text = bucket_name
     SubElement(root, "Prefix").text = prefix
@@ -1172,7 +1178,6 @@ def _bucket_list_versions_handler(bucket_name: str) -> Response:
             is_truncated = True
             break
         
-        # Add current version to response
         version = SubElement(root, "Version")
         SubElement(version, "Key").text = obj.key
         SubElement(version, "VersionId").text = "null"
@@ -1189,7 +1194,6 @@ def _bucket_list_versions_handler(bucket_name: str) -> Response:
         version_count += 1
         next_key_marker = obj.key
         
-        # Get historical versions
         try:
             versions = storage.list_object_versions(bucket_name, obj.key)
             for v in versions:
@@ -1273,14 +1277,12 @@ def _render_lifecycle_config(config: list) -> Element:
         rule_el = SubElement(root, "Rule")
         SubElement(rule_el, "ID").text = rule.get("ID", "")
         
-        # Filter
         filter_el = SubElement(rule_el, "Filter")
         if rule.get("Prefix"):
             SubElement(filter_el, "Prefix").text = rule.get("Prefix", "")
         
         SubElement(rule_el, "Status").text = rule.get("Status", "Enabled")
         
-        # Add expiration rule if present
         if "Expiration" in rule:
             exp = rule["Expiration"]
             exp_el = SubElement(rule_el, "Expiration")
@@ -1291,14 +1293,12 @@ def _render_lifecycle_config(config: list) -> Element:
             if exp.get("ExpiredObjectDeleteMarker"):
                 SubElement(exp_el, "ExpiredObjectDeleteMarker").text = "true"
         
-        # Add noncurrent version expiration if present
         if "NoncurrentVersionExpiration" in rule:
             nve = rule["NoncurrentVersionExpiration"]
             nve_el = SubElement(rule_el, "NoncurrentVersionExpiration")
             if "NoncurrentDays" in nve:
                 SubElement(nve_el, "NoncurrentDays").text = str(nve["NoncurrentDays"])
         
-        # Add incomplete multipart upload cleanup if present
         if "AbortIncompleteMultipartUpload" in rule:
             aimu = rule["AbortIncompleteMultipartUpload"]
             aimu_el = SubElement(rule_el, "AbortIncompleteMultipartUpload")
@@ -1322,29 +1322,24 @@ def _parse_lifecycle_config(payload: bytes) -> list:
     for rule_el in root.findall("{*}Rule") or root.findall("Rule"):
         rule: dict = {}
         
-        # Extract rule ID
         id_el = rule_el.find("{*}ID") or rule_el.find("ID")
         if id_el is not None and id_el.text:
             rule["ID"] = id_el.text.strip()
         
-        # Extract filter prefix
         filter_el = rule_el.find("{*}Filter") or rule_el.find("Filter")
         if filter_el is not None:
             prefix_el = filter_el.find("{*}Prefix") or filter_el.find("Prefix")
             if prefix_el is not None and prefix_el.text:
                 rule["Prefix"] = prefix_el.text
         
-        # Fall back to legacy Prefix element (outside Filter)
         if "Prefix" not in rule:
             prefix_el = rule_el.find("{*}Prefix") or rule_el.find("Prefix")
             if prefix_el is not None:
                 rule["Prefix"] = prefix_el.text or ""
         
-        # Extract status
         status_el = rule_el.find("{*}Status") or rule_el.find("Status")
         rule["Status"] = (status_el.text or "Enabled").strip() if status_el is not None else "Enabled"
         
-        # Parse expiration rule
         exp_el = rule_el.find("{*}Expiration") or rule_el.find("Expiration")
         if exp_el is not None:
             expiration: dict = {}
@@ -1360,7 +1355,6 @@ def _parse_lifecycle_config(payload: bytes) -> list:
             if expiration:
                 rule["Expiration"] = expiration
         
-        # NoncurrentVersionExpiration
         nve_el = rule_el.find("{*}NoncurrentVersionExpiration") or rule_el.find("NoncurrentVersionExpiration")
         if nve_el is not None:
             nve: dict = {}
@@ -1370,7 +1364,6 @@ def _parse_lifecycle_config(payload: bytes) -> list:
             if nve:
                 rule["NoncurrentVersionExpiration"] = nve
         
-        # AbortIncompleteMultipartUpload
         aimu_el = rule_el.find("{*}AbortIncompleteMultipartUpload") or rule_el.find("AbortIncompleteMultipartUpload")
         if aimu_el is not None:
             aimu: dict = {}
@@ -1408,7 +1401,6 @@ def _bucket_quota_handler(bucket_name: str) -> Response:
         if not quota:
             return _error_response("NoSuchQuotaConfiguration", "No quota configuration found", 404)
         
-        # Return as JSON for simplicity (not a standard S3 API)
         stats = storage.bucket_stats(bucket_name)
         return jsonify({
             "quota": quota,
@@ -1437,7 +1429,6 @@ def _bucket_quota_handler(bucket_name: str) -> Response:
     if max_size_bytes is None and max_objects is None:
         return _error_response("InvalidArgument", "At least one of max_size_bytes or max_objects is required", 400)
     
-    # Validate types
     if max_size_bytes is not None:
         try:
             max_size_bytes = int(max_size_bytes)
@@ -1548,7 +1539,6 @@ def _bulk_delete_handler(bucket_name: str) -> Response:
     return _xml_response(result, status=200)
 
 
-# Route handlers for S3 API endpoints
 @s3_api_bp.get("/")
 @limiter.limit("60 per minute")
 def list_buckets() -> Response:
@@ -1626,7 +1616,6 @@ def bucket_handler(bucket_name: str) -> Response:
         current_app.logger.info("Bucket deleted", extra={"bucket": bucket_name})
         return Response(status=204)
 
-    # Handle GET - list objects (supports both ListObjects and ListObjectsV2)
     principal, error = _require_principal()
     try:
         _authorize_action(principal, bucket_name, "list")
@@ -1640,7 +1629,6 @@ def bucket_handler(bucket_name: str) -> Response:
     delimiter = request.args.get("delimiter", "")
     max_keys = min(int(request.args.get("max-keys", current_app.config["UI_PAGE_SIZE"])), 1000)
     
-    # Use appropriate markers for pagination depending on API version
     marker = request.args.get("marker", "")  # ListObjects v1
     continuation_token = request.args.get("continuation-token", "")  # ListObjectsV2
     start_after = request.args.get("start-after", "")  # ListObjectsV2
@@ -1660,7 +1648,6 @@ def bucket_handler(bucket_name: str) -> Response:
     else:
         effective_start = marker
     
-    # Fetch with buffer for delimiter processing; delimiter requires extra objects to compute prefixes
     fetch_keys = max_keys * 10 if delimiter else max_keys
     try:
         list_result = storage.list_objects(
@@ -1680,7 +1667,6 @@ def bucket_handler(bucket_name: str) -> Response:
         for obj in objects:
             key_after_prefix = obj.key[len(prefix):] if prefix else obj.key
             if delimiter in key_after_prefix:
-                # Extract common prefix (folder-like structure)
                 common_prefix = prefix + key_after_prefix.split(delimiter)[0] + delimiter
                 if common_prefix not in seen_prefixes:
                     seen_prefixes.add(common_prefix)
@@ -1778,7 +1764,6 @@ def object_handler(bucket_name: str, object_key: str):
     if "tagging" in request.args:
         return _object_tagging_handler(bucket_name, object_key)
 
-    # Multipart Uploads
     if request.method == "POST":
         if "uploads" in request.args:
             return _initiate_multipart_upload(bucket_name, object_key)
@@ -1831,7 +1816,6 @@ def object_handler(bucket_name: str, object_key: str):
         response = Response(status=200)
         response.headers["ETag"] = f'"{meta.etag}"'
         
-        # Trigger replication for non-replication requests
         if "S3ReplicationAgent" not in request.headers.get("User-Agent", ""):
             _replication_manager().trigger_replication(bucket_name, object_key, action="write")
             
@@ -1851,7 +1835,6 @@ def object_handler(bucket_name: str, object_key: str):
         metadata = storage.get_object_metadata(bucket_name, object_key)
         mimetype = mimetypes.guess_type(object_key)[0] or "application/octet-stream"
         
-        # Decrypt encrypted objects
         is_encrypted = "x-amz-server-side-encryption" in metadata
         
         if request.method == "GET":
@@ -1865,15 +1848,12 @@ def object_handler(bucket_name: str, object_key: str):
                 except StorageError as exc:
                     return _error_response("InternalError", str(exc), 500)
             else:
-                # Stream unencrypted file directly
                 stat = path.stat()
                 response = Response(_stream_file(path), mimetype=mimetype, direct_passthrough=True)
                 logged_bytes = stat.st_size
                 etag = storage._compute_etag(path)
         else:
-            # HEAD request
             if is_encrypted and hasattr(storage, 'get_object_data'):
-                # For encrypted objects, we need to report decrypted size
                 try:
                     data, _ = storage.get_object_data(bucket_name, object_key)
                     response = Response(status=200)
@@ -1902,7 +1882,6 @@ def object_handler(bucket_name: str, object_key: str):
     storage.delete_object(bucket_name, object_key)
     current_app.logger.info("Object deleted", extra={"bucket": bucket_name, "key": object_key})
     
-    # Trigger replication if not a replication request
     user_agent = request.headers.get("User-Agent", "")
     if "S3ReplicationAgent" not in user_agent:
         _replication_manager().trigger_replication(bucket_name, object_key, action="delete")
@@ -2183,7 +2162,6 @@ class AwsChunkedDecoder:
                 self.chunk_remaining -= len(chunk)
                 
                 if self.chunk_remaining == 0:
-                    # Read CRLF after chunk data
                     crlf = self.stream.read(2)
                     if crlf != b"\r\n":
                         raise IOError("Malformed chunk: missing CRLF")
@@ -2202,7 +2180,6 @@ class AwsChunkedDecoder:
                 
                 try:
                     line_str = line.decode("ascii").strip()
-                    # Handle chunk-signature extension if present (e.g. "1000;chunk-signature=...")
                     if ";" in line_str:
                         line_str = line_str.split(";")[0]
                     chunk_size = int(line_str, 16)
@@ -2358,7 +2335,6 @@ def _abort_multipart_upload(bucket_name: str, object_key: str) -> Response:
     try:
         _storage().abort_multipart_upload(bucket_name, upload_id)
     except StorageError as exc:
-        # Abort is idempotent, but if bucket missing...
         if "Bucket does not exist" in str(exc):
             return _error_response("NoSuchBucket", str(exc), 404)
             
@@ -2368,7 +2344,6 @@ def _abort_multipart_upload(bucket_name: str, object_key: str) -> Response:
 @s3_api_bp.before_request
 def resolve_principal():
     g.principal = None
-    # Try SigV4
     try:
         if ("Authorization" in request.headers and request.headers["Authorization"].startswith("AWS4-HMAC-SHA256")) or \
            (request.args.get("X-Amz-Algorithm") == "AWS4-HMAC-SHA256"):
@@ -2377,7 +2352,6 @@ def resolve_principal():
     except Exception:
         pass
     
-    # Try simple auth headers (internal/testing)
     access_key = request.headers.get("X-Access-Key")
     secret_key = request.headers.get("X-Secret-Key")
     if access_key and secret_key:

app/ui.py

@@ -189,7 +189,7 @@ def inject_nav_state() -> dict[str, Any]:
     return {
         "principal": principal,
         "can_manage_iam": can_manage,
-        "can_view_metrics": can_manage,  # Only admins can view metrics
+        "can_view_metrics": can_manage, 
         "csrf_token": generate_csrf,
     }
 
@@ -294,7 +294,6 @@ def bucket_detail(bucket_name: str):
     storage = _storage()
     try:
         _authorize_ui(principal, bucket_name, "list")
-        # Don't load objects here - UI fetches them asynchronously via /buckets/<name>/objects
         if not storage.bucket_exists(bucket_name):
             raise StorageError("Bucket does not exist")
     except (StorageError, IamError) as exc:
@@ -343,7 +342,6 @@ def bucket_detail(bucket_name: str):
         except IamError:
             can_manage_versioning = False
 
-    # Check replication permission
     can_manage_replication = False
     if principal:
         try:
@@ -352,7 +350,6 @@ def bucket_detail(bucket_name: str):
         except IamError:
             can_manage_replication = False
 
-    # Check if user is admin (can configure replication settings, not just toggle)
     is_replication_admin = False
     if principal:
         try:
@@ -361,12 +358,9 @@ def bucket_detail(bucket_name: str):
         except IamError:
             is_replication_admin = False
 
-    # Replication info - don't compute sync status here (it's slow), let JS fetch it async
     replication_rule = _replication().get_rule(bucket_name)
-    # Load connections for admin, or for non-admin if there's an existing rule (to show target name)
     connections = _connections().list() if (is_replication_admin or replication_rule) else []
 
-    # Encryption settings
     encryption_config = storage.get_bucket_encryption(bucket_name)
     kms_manager = _kms()
     kms_keys = kms_manager.list_keys() if kms_manager else []
@@ -374,7 +368,6 @@ def bucket_detail(bucket_name: str):
     encryption_enabled = current_app.config.get("ENCRYPTION_ENABLED", False)
     can_manage_encryption = can_manage_versioning  # Same as other bucket properties
 
-    # Quota settings (admin only)
     bucket_quota = storage.get_bucket_quota(bucket_name)
     bucket_stats = storage.bucket_stats(bucket_name)
     can_manage_quota = False
@@ -384,7 +377,6 @@ def bucket_detail(bucket_name: str):
     except IamError:
         pass
 
-    # Pass the objects API endpoint URL for async loading
     objects_api_url = url_for("ui.list_bucket_objects", bucket_name=bucket_name)
 
     return render_template(
@@ -1256,7 +1248,6 @@ def delete_iam_user(access_key: str):
         return redirect(url_for("ui.iam_dashboard"))
 
     if access_key == principal.access_key:
-        # Self-deletion
         try:
             _iam().delete_user(access_key)
             session.pop("credentials", None)
@@ -1338,6 +1329,9 @@ def create_connection():
 
 @ui_bp.post("/connections/test")
 def test_connection():
+    from botocore.config import Config as BotoConfig
+    from botocore.exceptions import ConnectTimeoutError, EndpointConnectionError, ReadTimeoutError
+    
     principal = _current_principal()
     try:
         _iam().authorize(principal, None, "iam:list_users")
@@ -1354,18 +1348,32 @@ def test_connection():
         return jsonify({"status": "error", "message": "Missing credentials"}), 400
 
     try:
+        config = BotoConfig(
+            connect_timeout=5,
+            read_timeout=10,
+            retries={'max_attempts': 1}
+        )
         s3 = boto3.client(
             "s3",
             endpoint_url=endpoint,
             aws_access_key_id=access_key,
             aws_secret_access_key=secret_key,
             region_name=region,
+            config=config,
         )
-        # Try to list buckets to verify credentials and endpoint
+
         s3.list_buckets()
         return jsonify({"status": "ok", "message": "Connection successful"})
+    except (ConnectTimeoutError, ReadTimeoutError):
+        return jsonify({"status": "error", "message": f"Connection timed out - endpoint may be down or unreachable: {endpoint}"}), 400
+    except EndpointConnectionError:
+        return jsonify({"status": "error", "message": f"Could not connect to endpoint: {endpoint}"}), 400
+    except ClientError as e:
+        error_code = e.response.get('Error', {}).get('Code', 'Unknown')
+        error_msg = e.response.get('Error', {}).get('Message', str(e))
+        return jsonify({"status": "error", "message": f"Connection failed ({error_code}): {error_msg}"}), 400
     except Exception as e:
-        return jsonify({"status": "error", "message": str(e)}), 400
+        return jsonify({"status": "error", "message": f"Connection failed: {str(e)}"}), 400
 
 
 @ui_bp.post("/connections/<connection_id>/update")
@@ -1426,7 +1434,6 @@ def update_bucket_replication(bucket_name: str):
         flash(str(exc), "danger")
         return redirect(url_for("ui.bucket_detail", bucket_name=bucket_name, tab="replication"))
     
-    # Check if user is admin (required for create/delete operations)
     is_admin = False
     try:
         _iam().authorize(principal, None, "iam:list_users")
@@ -1437,14 +1444,12 @@ def update_bucket_replication(bucket_name: str):
     action = request.form.get("action")
     
     if action == "delete":
-        # Admin only - remove configuration entirely
         if not is_admin:
             flash("Only administrators can remove replication configuration", "danger")
             return redirect(url_for("ui.bucket_detail", bucket_name=bucket_name, tab="replication"))
         _replication().delete_rule(bucket_name)
         flash("Replication configuration removed", "info")
     elif action == "pause":
-        # Users can pause - just set enabled=False
         rule = _replication().get_rule(bucket_name)
         if rule:
             rule.enabled = False
@@ -1453,7 +1458,6 @@ def update_bucket_replication(bucket_name: str):
         else:
             flash("No replication configuration to pause", "warning")
     elif action == "resume":
-        # Users can resume - just set enabled=True
         rule = _replication().get_rule(bucket_name)
         if rule:
             rule.enabled = True
@@ -1462,7 +1466,6 @@ def update_bucket_replication(bucket_name: str):
         else:
             flash("No replication configuration to resume", "warning")
     elif action == "create":
-        # Admin only - create new configuration
         if not is_admin:
             flash("Only administrators can configure replication settings", "danger")
             return redirect(url_for("ui.bucket_detail", bucket_name=bucket_name, tab="replication"))
@@ -1487,7 +1490,6 @@ def update_bucket_replication(bucket_name: str):
             )
             _replication().set_rule(rule)
             
-            # If mode is "all", trigger replication of existing objects
             if replication_mode == REPLICATION_MODE_ALL:
                 _replication().replicate_existing_objects(bucket_name)
                 flash("Replication configured. Existing objects are being replicated in the background.", "success")
@@ -1512,10 +1514,31 @@ def get_replication_status(bucket_name: str):
     if not rule:
         return jsonify({"error": "No replication rule"}), 404
     
-    # This is the slow operation - compute sync status by comparing buckets
+    connection = _connections().get(rule.target_connection_id)
-    stats = _replication().get_sync_status(bucket_name)
+    endpoint_healthy = False
+    endpoint_error = None
+    if connection:
+        endpoint_healthy = _replication().check_endpoint_health(connection)
+        if not endpoint_healthy:
+            endpoint_error = f"Cannot reach endpoint: {connection.endpoint_url}"
+    else:
+        endpoint_error = "Target connection not found"
+    
+    stats = None
+    if endpoint_healthy:
+        stats = _replication().get_sync_status(bucket_name)
+    
     if not stats:
-        return jsonify({"error": "Failed to compute status"}), 500
+        return jsonify({
+            "objects_synced": 0,
+            "objects_pending": 0,
+            "objects_orphaned": 0,
+            "bytes_synced": 0,
+            "last_sync_at": rule.stats.last_sync_at if rule.stats else None,
+            "last_sync_key": rule.stats.last_sync_key if rule.stats else None,
+            "endpoint_healthy": endpoint_healthy,
+            "endpoint_error": endpoint_error,
+        })
     
     return jsonify({
         "objects_synced": stats.objects_synced,
@@ -1524,6 +1547,28 @@ def get_replication_status(bucket_name: str):
         "bytes_synced": stats.bytes_synced,
         "last_sync_at": stats.last_sync_at,
         "last_sync_key": stats.last_sync_key,
+        "endpoint_healthy": endpoint_healthy,
+        "endpoint_error": endpoint_error,
+    })
+
+
+@ui_bp.get("/connections/<connection_id>/health")
+def check_connection_health(connection_id: str):
+    """Check if a connection endpoint is reachable."""
+    principal = _current_principal()
+    try:
+        _iam().authorize(principal, None, "iam:list_users")
+    except IamError:
+        return jsonify({"error": "Access denied"}), 403
+    
+    conn = _connections().get(connection_id)
+    if not conn:
+        return jsonify({"healthy": False, "error": "Connection not found"}), 404
+    
+    healthy = _replication().check_endpoint_health(conn)
+    return jsonify({
+        "healthy": healthy,
+        "error": None if healthy else f"Cannot reach endpoint: {conn.endpoint_url}"
     })
 
 
@@ -1544,7 +1589,6 @@ def connections_dashboard():
 def metrics_dashboard():
     principal = _current_principal()
     
-    # Metrics are restricted to admin users
     try:
         _iam().authorize(principal, None, "iam:list_users")
     except IamError:
@@ -1568,16 +1612,13 @@ def metrics_dashboard():
     total_bytes_used = 0
     total_versions = 0
     
-    # Note: Uses cached stats from storage layer to improve performance
     cache_ttl = current_app.config.get("BUCKET_STATS_CACHE_TTL", 60)
     for bucket in buckets:
         stats = storage.bucket_stats(bucket.name, cache_ttl=cache_ttl)
-        # Use totals which include archived versions
         total_objects += stats.get("total_objects", stats.get("objects", 0))
         total_bytes_used += stats.get("total_bytes", stats.get("bytes", 0))
         total_versions += stats.get("version_count", 0)
     
-    # Calculate system uptime
     boot_time = psutil.boot_time()
     uptime_seconds = time.time() - boot_time
     uptime_days = int(uptime_seconds / 86400)

static/css/main.css

@@ -66,8 +66,28 @@ html {
 	color: var(--myfsio-muted) !important;
 }
 
-.table-responsive { border-radius: 0.5rem; overflow: hidden; }
+.table-responsive { 
+	border-radius: 0.5rem; 
+	overflow-x: auto; 
+	-webkit-overflow-scrolling: touch;
+}
 .message-stack { position: sticky; top: 1rem; z-index: 100; }
+
+/* Mobile-friendly table improvements */
+.table-responsive table {
+	min-width: 600px;
+}
+
+.table-responsive table th,
+.table-responsive table td {
+	white-space: nowrap;
+}
+
+/* Allow text wrapping for description columns */
+.table-responsive table td.text-wrap {
+	white-space: normal;
+	min-width: 200px;
+}
 code { font-size: 0.85rem; }
 
 code {
@@ -1553,6 +1573,41 @@ pre code {
 		position: relative !important;
 		top: 0 !important;
 	}
+	
+	/* Ensure tables are scrollable on mobile */
+	.card-body .table-responsive {
+		margin: -1rem;
+		padding: 0;
+		width: calc(100% + 2rem);
+	}
+	
+	.card-body .table-responsive table {
+		margin-bottom: 0;
+	}
+	
+	/* IAM users table mobile adjustments */
+	.table th,
+	.table td {
+		padding: 0.5rem 0.75rem;
+	}
+	
+	/* Better touch scrolling indicator */
+	.table-responsive::after {
+		content: '';
+		position: absolute;
+		top: 0;
+		right: 0;
+		bottom: 0;
+		width: 20px;
+		background: linear-gradient(to left, var(--myfsio-card-bg), transparent);
+		pointer-events: none;
+		opacity: 0;
+		transition: opacity 0.3s;
+	}
+	
+	.table-responsive:not(:hover)::after {
+		opacity: 0.8;
+	}
 }
 
 *:focus-visible {

templates/bucket_detail.html

@@ -954,7 +954,7 @@
             </div>
             <div class="card-body">
               {% if replication_rule and replication_rule.enabled %}
-              <div class="alert alert-success d-flex align-items-center mb-4" role="alert">
+              <div id="replication-status-alert" class="alert alert-success d-flex align-items-center mb-4" role="alert">
                 <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" fill="currentColor" class="bi bi-check-circle-fill flex-shrink-0 me-2" viewBox="0 0 16 16">
                   <path d="M16 8A8 8 0 1 1 0 8a8 8 0 0 1 16 0zm-3.97-3.03a.75.75 0 0 0-1.08.022L7.477 9.417 5.384 7.323a.75.75 0 0 0-1.06 1.06L6.97 11.03a.75.75 0 0 0 1.079-.02l3.992-4.99a.75.75 0 0 0-.01-1.05z"/>
                 </svg>
@@ -968,6 +968,19 @@
                 </div>
               </div>
               
+              <!-- Warning alert for unreachable endpoint (shown by JS if endpoint is down) -->
+              <div id="replication-endpoint-warning" class="alert alert-danger d-none mb-4" role="alert">
+                <div class="d-flex align-items-start">
+                  <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" fill="currentColor" class="flex-shrink-0 me-2" viewBox="0 0 16 16">
+                    <path d="M8.982 1.566a1.13 1.13 0 0 0-1.96 0L.165 13.233c-.457.778.091 1.767.98 1.767h13.713c.889 0 1.438-.99.98-1.767L8.982 1.566zM8 5c.535 0 .954.462.9.995l-.35 3.507a.552.552 0 0 1-1.1 0L7.1 5.995A.905.905 0 0 1 8 5zm.002 6a1 1 0 1 1 0 2 1 1 0 0 1 0-2z"/>
+                  </svg>
+                  <div>
+                    <strong>Replication Endpoint Unreachable</strong>
+                    <p class="mb-0 small" id="replication-endpoint-error">The target endpoint is not responding. Replication is paused until the endpoint is available.</p>
+                  </div>
+                </div>
+              </div>
+              
               <div class="row g-3 mb-4" id="replication-stats-cards" data-status-endpoint="{{ url_for('ui.get_replication_status', bucket_name=bucket_name) }}">
                 <div class="col-6 col-lg">
                   <div class="card bg-body-tertiary border-0 h-100">
@@ -1090,11 +1103,11 @@
                       {% endif %}
                     </div>
                     <div class="col-auto">
-                      <span class="badge bg-success-subtle text-success px-3 py-2">
+                      <span id="replication-status-badge" class="badge bg-success-subtle text-success px-3 py-2">
                         <svg xmlns="http://www.w3.org/2000/svg" width="12" height="12" fill="currentColor" class="me-1" viewBox="0 0 16 16">
                           <path d="M16 8A8 8 0 1 1 0 8a8 8 0 0 1 16 0zm-3.97-3.03a.75.75 0 0 0-1.08.022L7.477 9.417 5.384 7.323a.75.75 0 0 0-1.06 1.06L6.97 11.03a.75.75 0 0 0 1.079-.02l3.992-4.99a.75.75 0 0 0-.01-1.05z"/>
                         </svg>
-                        Enabled
+                        <span id="replication-status-text">Enabled</span>
                       </span>
                     </div>
                   </div>
@@ -1109,7 +1122,7 @@
                   </svg>
                   Refresh
                 </a>
-                <form method="POST" action="{{ url_for('ui.update_bucket_replication', bucket_name=bucket_name) }}" class="d-inline">
+                <form id="pause-replication-form" method="POST" action="{{ url_for('ui.update_bucket_replication', bucket_name=bucket_name) }}" class="d-inline">
                   <input type="hidden" name="csrf_token" value="{{ csrf_token() }}" />
                   <input type="hidden" name="action" value="pause">
                   <button type="submit" class="btn btn-outline-warning">
@@ -2033,17 +2046,19 @@
       const slashIndex = remainder.indexOf('/');
       
       if (slashIndex === -1) {
-        // File in current folder
+        // File in current folder - filter on the displayed filename (remainder)
-        if (!currentFilterTerm || obj.key.toLowerCase().includes(currentFilterTerm)) {
+        if (!currentFilterTerm || remainder.toLowerCase().includes(currentFilterTerm)) {
           items.push({ type: 'file', data: obj, displayKey: remainder });
         }
       } else {
         // Folder
-        const folderPath = currentPrefix + remainder.slice(0, slashIndex + 1);
+        const folderName = remainder.slice(0, slashIndex);
+        const folderPath = currentPrefix + folderName + '/';
         if (!folders.has(folderPath)) {
           folders.add(folderPath);
-          if (!currentFilterTerm || folderPath.toLowerCase().includes(currentFilterTerm)) {
+          // Filter on the displayed folder name only
-            items.push({ type: 'folder', path: folderPath, displayKey: remainder.slice(0, slashIndex) });
+          if (!currentFilterTerm || folderName.toLowerCase().includes(currentFilterTerm)) {
+            items.push({ type: 'folder', path: folderPath, displayKey: folderName });
           }
         }
       }
@@ -3408,33 +3423,9 @@
     currentFilterTerm = event.target.value.toLowerCase();
     updateFilterWarning();
     
-    if (hasFolders()) {
+    // Use the virtual scrolling system for filtering - it properly handles
-      const { folders, files } = getFoldersAtPrefix(currentPrefix);
+    // both folder view and flat view, and works with large object counts
-      const tbody = objectsTableBody;
+    refreshVirtualList();
-
-      tbody.innerHTML = '';
-
-      folders.forEach(folderPath => {
-        const folderName = folderPath.slice(currentPrefix.length).replace(/\/$/, '').toLowerCase();
-        if (folderName.includes(currentFilterTerm)) {
-          tbody.appendChild(createFolderRow(folderPath));
-        }
-      });
-
-      files.forEach(obj => {
-        const keyName = obj.key.slice(currentPrefix.length).toLowerCase();
-        if (keyName.includes(currentFilterTerm)) {
-          tbody.appendChild(obj.element);
-          obj.element.style.display = '';
-        }
-      });
-    } else {
-      // Filter all loaded objects (including newly loaded ones)
-      document.querySelectorAll('[data-object-row]').forEach((row) => {
-        const key = row.dataset.key.toLowerCase();
-        row.style.display = key.includes(currentFilterTerm) ? '' : 'none';
-      });
-    }
   });
 
   refreshVersionsButton?.addEventListener('click', () => {
@@ -3875,6 +3866,12 @@
     const lastSyncEl = document.getElementById('replication-last-sync');
     const lastSyncTimeEl = document.querySelector('[data-stat="last-sync-time"]');
     const lastSyncKeyEl = document.querySelector('[data-stat="last-sync-key"]');
+    const endpointWarning = document.getElementById('replication-endpoint-warning');
+    const endpointErrorEl = document.getElementById('replication-endpoint-error');
+    const statusAlert = document.getElementById('replication-status-alert');
+    const statusBadge = document.getElementById('replication-status-badge');
+    const statusText = document.getElementById('replication-status-text');
+    const pauseForm = document.getElementById('pause-replication-form');
 
     const loadReplicationStats = async () => {
       try {
@@ -3882,6 +3879,48 @@
         if (!resp.ok) throw new Error('Failed to fetch stats');
         const data = await resp.json();
 
+        // Handle endpoint health status
+        if (data.endpoint_healthy === false) {
+          // Show warning and hide success alert
+          if (endpointWarning) {
+            endpointWarning.classList.remove('d-none');
+            if (endpointErrorEl && data.endpoint_error) {
+              endpointErrorEl.textContent = data.endpoint_error + '. Replication is paused until the endpoint is available.';
+            }
+          }
+          if (statusAlert) statusAlert.classList.add('d-none');
+          
+          // Update status badge to show "Paused" with warning styling
+          if (statusBadge) {
+            statusBadge.className = 'badge bg-warning-subtle text-warning px-3 py-2';
+            statusBadge.innerHTML = `
+              <svg xmlns="http://www.w3.org/2000/svg" width="12" height="12" fill="currentColor" class="me-1" viewBox="0 0 16 16">
+                <path d="M5.5 3.5A1.5 1.5 0 0 1 7 5v6a1.5 1.5 0 0 1-3 0V5a1.5 1.5 0 0 1 1.5-1.5zm5 0A1.5 1.5 0 0 1 12 5v6a1.5 1.5 0 0 1-3 0V5a1.5 1.5 0 0 1 1.5-1.5z"/>
+              </svg>
+              <span>Paused (Endpoint Unavailable)</span>`;
+          }
+          
+          // Hide the pause button since replication is effectively already paused
+          if (pauseForm) pauseForm.classList.add('d-none');
+        } else {
+          // Hide warning and show success alert
+          if (endpointWarning) endpointWarning.classList.add('d-none');
+          if (statusAlert) statusAlert.classList.remove('d-none');
+          
+          // Restore status badge to show "Enabled"
+          if (statusBadge) {
+            statusBadge.className = 'badge bg-success-subtle text-success px-3 py-2';
+            statusBadge.innerHTML = `
+              <svg xmlns="http://www.w3.org/2000/svg" width="12" height="12" fill="currentColor" class="me-1" viewBox="0 0 16 16">
+                <path d="M16 8A8 8 0 1 1 0 8a8 8 0 0 1 16 0zm-3.97-3.03a.75.75 0 0 0-1.08.022L7.477 9.417 5.384 7.323a.75.75 0 0 0-1.06 1.06L6.97 11.03a.75.75 0 0 0 1.079-.02l3.992-4.99a.75.75 0 0 0-.01-1.05z"/>
+              </svg>
+              <span>Enabled</span>`;
+          }
+          
+          // Show the pause button
+          if (pauseForm) pauseForm.classList.remove('d-none');
+        }
+
         if (syncedEl) syncedEl.textContent = data.objects_synced;
         if (pendingEl) {
           pendingEl.textContent = data.objects_pending;

templates/connections.html

@@ -104,6 +104,7 @@
                     <table class="table table-hover align-middle mb-0">
                         <thead class="table-light">
                             <tr>
+                                <th scope="col" style="width: 50px;">Status</th>
                                 <th scope="col">Name</th>
                                 <th scope="col">Endpoint</th>
                                 <th scope="col">Region</th>
@@ -113,7 +114,12 @@
                         </thead>
                         <tbody>
                             {% for conn in connections %}
-                            <tr>
+                            <tr data-connection-id="{{ conn.id }}">
+                                <td class="text-center">
+                                    <span class="connection-status" data-status="checking" title="Checking...">
+                                        <span class="spinner-border spinner-border-sm text-muted" role="status" style="width: 12px; height: 12px;"></span>
+                                    </span>
+                                </td>
                                 <td>
                                     <div class="d-flex align-items-center gap-2">
                                         <div class="connection-icon">
@@ -301,7 +307,11 @@
         const formData = new FormData(form);
         const data = Object.fromEntries(formData.entries());
         
-        resultDiv.innerHTML = '<div class="text-info"><span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span> Testing...</div>';
+        resultDiv.innerHTML = '<div class="text-info"><span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span> Testing connection...</div>';
+        
+        // Use AbortController to timeout client-side after 20 seconds
+        const controller = new AbortController();
+        const timeoutId = setTimeout(() => controller.abort(), 20000);
         
         try {
             const response = await fetch("{{ url_for('ui.test_connection') }}", {
@@ -310,17 +320,44 @@
                     "Content-Type": "application/json",
                     "X-CSRFToken": "{{ csrf_token() }}"
                 },
-                body: JSON.stringify(data)
+                body: JSON.stringify(data),
+                signal: controller.signal
             });
+            clearTimeout(timeoutId);
             
             const result = await response.json();
             if (response.ok) {
-                resultDiv.innerHTML = `<div class="text-success"><i class="bi bi-check-circle"></i> ${result.message}</div>`;
+                resultDiv.innerHTML = `<div class="text-success">
+                    <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="me-1" viewBox="0 0 16 16">
+                        <path d="M16 8A8 8 0 1 1 0 8a8 8 0 0 1 16 0zm-3.97-3.03a.75.75 0 0 0-1.08.022L7.477 9.417 5.384 7.323a.75.75 0 0 0-1.06 1.06L6.97 11.03a.75.75 0 0 0 1.079-.02l3.992-4.99a.75.75 0 0 0-.01-1.05z"/>
+                    </svg>
+                    ${result.message}
+                </div>`;
             } else {
-                resultDiv.innerHTML = `<div class="text-danger"><i class="bi bi-exclamation-circle"></i> ${result.message}</div>`;
+                resultDiv.innerHTML = `<div class="text-danger">
+                    <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="me-1" viewBox="0 0 16 16">
+                        <path d="M16 8A8 8 0 1 1 0 8a8 8 0 0 1 16 0zM5.354 4.646a.5.5 0 1 0-.708.708L7.293 8l-2.647 2.646a.5.5 0 0 0 .708.708L8 8.707l2.646 2.647a.5.5 0 0 0 .708-.708L8.707 8l2.647-2.646a.5.5 0 0 0-.708-.708L8 7.293 5.354 4.646z"/>
+                    </svg>
+                    ${result.message}
+                </div>`;
             }
         } catch (error) {
-            resultDiv.innerHTML = `<div class="text-danger"><i class="bi bi-exclamation-circle"></i> Connection failed</div>`;
+            clearTimeout(timeoutId);
+            if (error.name === 'AbortError') {
+                resultDiv.innerHTML = `<div class="text-danger">
+                    <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="me-1" viewBox="0 0 16 16">
+                        <path d="M16 8A8 8 0 1 1 0 8a8 8 0 0 1 16 0zM5.354 4.646a.5.5 0 1 0-.708.708L7.293 8l-2.647 2.646a.5.5 0 0 0 .708.708L8 8.707l2.646 2.647a.5.5 0 0 0 .708-.708L8.707 8l2.647-2.646a.5.5 0 0 0-.708-.708L8 7.293 5.354 4.646z"/>
+                    </svg>
+                    Connection test timed out - endpoint may be unreachable
+                </div>`;
+            } else {
+                resultDiv.innerHTML = `<div class="text-danger">
+                    <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="me-1" viewBox="0 0 16 16">
+                        <path d="M16 8A8 8 0 1 1 0 8a8 8 0 0 1 16 0zM5.354 4.646a.5.5 0 1 0-.708.708L7.293 8l-2.647 2.646a.5.5 0 0 0 .708.708L8 8.707l2.646 2.647a.5.5 0 0 0 .708-.708L8.707 8l2.647-2.646a.5.5 0 0 0-.708-.708L8 7.293 5.354 4.646z"/>
+                    </svg>
+                    Connection failed: Network error
+                </div>`;
+            }
         }
     }
 
@@ -358,5 +395,54 @@
         const form = document.getElementById('deleteConnectionForm');
         form.action = "{{ url_for('ui.delete_connection', connection_id='CONN_ID') }}".replace('CONN_ID', id);
     });
+
+    // Check connection health for each connection in the table
+    // Uses staggered requests to avoid overwhelming the server
+    async function checkConnectionHealth(connectionId, statusEl) {
+        try {
+            const controller = new AbortController();
+            const timeoutId = setTimeout(() => controller.abort(), 15000);
+            
+            const response = await fetch(`/ui/connections/${connectionId}/health`, {
+                signal: controller.signal
+            });
+            clearTimeout(timeoutId);
+            
+            const data = await response.json();
+            if (data.healthy) {
+                statusEl.innerHTML = `
+                    <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="text-success" viewBox="0 0 16 16">
+                        <path d="M16 8A8 8 0 1 1 0 8a8 8 0 0 1 16 0zm-3.97-3.03a.75.75 0 0 0-1.08.022L7.477 9.417 5.384 7.323a.75.75 0 0 0-1.06 1.06L6.97 11.03a.75.75 0 0 0 1.079-.02l3.992-4.99a.75.75 0 0 0-.01-1.05z"/>
+                    </svg>`;
+                statusEl.setAttribute('data-status', 'healthy');
+                statusEl.setAttribute('title', 'Connected');
+            } else {
+                statusEl.innerHTML = `
+                    <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="text-danger" viewBox="0 0 16 16">
+                        <path d="M16 8A8 8 0 1 1 0 8a8 8 0 0 1 16 0zM5.354 4.646a.5.5 0 1 0-.708.708L7.293 8l-2.647 2.646a.5.5 0 0 0 .708.708L8 8.707l2.646 2.647a.5.5 0 0 0 .708-.708L8.707 8l2.647-2.646a.5.5 0 0 0-.708-.708L8 7.293 5.354 4.646z"/>
+                    </svg>`;
+                statusEl.setAttribute('data-status', 'unhealthy');
+                statusEl.setAttribute('title', data.error || 'Unreachable');
+            }
+        } catch (error) {
+            statusEl.innerHTML = `
+                <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="text-warning" viewBox="0 0 16 16">
+                    <path d="M8.982 1.566a1.13 1.13 0 0 0-1.96 0L.165 13.233c-.457.778.091 1.767.98 1.767h13.713c.889 0 1.438-.99.98-1.767L8.982 1.566zM8 5c.535 0 .954.462.9.995l-.35 3.507a.552.552 0 0 1-1.1 0L7.1 5.995A.905.905 0 0 1 8 5zm.002 6a1 1 0 1 1 0 2 1 1 0 0 1 0-2z"/>
+                </svg>`;
+            statusEl.setAttribute('data-status', 'unknown');
+            statusEl.setAttribute('title', 'Could not check status');
+        }
+    }
+
+    // Stagger health checks to avoid all requests at once
+    const connectionRows = document.querySelectorAll('tr[data-connection-id]');
+    connectionRows.forEach((row, index) => {
+        const connectionId = row.getAttribute('data-connection-id');
+        const statusEl = row.querySelector('.connection-status');
+        if (statusEl) {
+            // Stagger requests by 200ms each
+            setTimeout(() => checkConnectionHealth(connectionId, statusEl), index * 200);
+        }
+    });
 </script>
 {% endblock %}

templates/docs.html

@@ -47,9 +47,9 @@ python run.py --mode ui
           <table class="table table-sm table-bordered small mb-0">
             <thead class="table-light">
               <tr>
-                <th>Variable</th>
+                <th style="min-width: 180px;">Variable</th>
-                <th>Default</th>
+                <th style="min-width: 120px;">Default</th>
-                <th>Description</th>
+                <th class="text-wrap" style="min-width: 250px;">Description</th>
               </tr>
             </thead>
             <tbody>