feat: pluggable bank sync connector architecture (#75)

packages/backend/app/routes/__init__.py

@@ -7,6 +7,7 @@
 from .categories import bp as categories_bp
 from .docs import bp as docs_bp
 from .dashboard import bp as dashboard_bp
+from .bank_sync import bp as bank_sync_bp
 
 
 def register_routes(app: Flask):
@@ -18,3 +19,4 @@ def register_routes(app: Flask):
     app.register_blueprint(categories_bp, url_prefix="/categories")
     app.register_blueprint(docs_bp, url_prefix="/docs")
     app.register_blueprint(dashboard_bp, url_prefix="/dashboard")
+    app.register_blueprint(bank_sync_bp, url_prefix="")

packages/backend/app/routes/bank_sync.py

@@ -0,0 +1,108 @@
+"""Routes for Bank Sync Connector Architecture (issue #75)."""
+from flask import Blueprint, request, jsonify
+from flask_jwt_extended import jwt_required, get_jwt_identity
+from app.services.bank_sync import (
+    create_connector,
+    list_connectors,
+    get_connector_class,
+    SyncResult,
+)
+
+bp = Blueprint("bank_sync", __name__)
+
+
+@bp.route("/bank-sync/connectors", methods=["GET"])
+def get_connectors():
+    """List all available bank connectors."""
+    connectors = list_connectors()
+    return jsonify({"connectors": connectors, "count": len(connectors)}), 200
+
+
+@bp.route("/bank-sync/validate", methods=["POST"])
+@jwt_required()
+def validate_connector():
+    """Validate connector credentials without importing data."""
+    data = request.get_json() or {}
+    connector_name = data.get("connector")
+    credentials = data.get("credentials", {})
+
+    if not connector_name:
+        return jsonify({"error": "connector name is required"}), 400
+
+    connector = create_connector(connector_name, credentials, data.get("options", {}))
+    if not connector:
+        return jsonify({"error": f"Unknown connector: {connector_name}"}), 404
+
+    is_valid = connector.validate_credentials()
+    return jsonify({
+        "connector": connector_name,
+        "valid": is_valid,
+        "message": "Credentials valid" if is_valid else "Invalid credentials",
+    }), 200
+
+
+@bp.route("/bank-sync/import", methods=["POST"])
+@jwt_required()
+def import_transactions():
+    """Import transactions using the specified connector."""
+    data = request.get_json() or {}
+    connector_name = data.get("connector")
+    account_id = data.get("account_id", "default")
+    credentials = data.get("credentials", {})
+    options = data.get("options", {})
+
+    if not connector_name:
+        return jsonify({"error": "connector name is required"}), 400
+
+    connector = create_connector(connector_name, credentials, options)
+    if not connector:
+        return jsonify({"error": f"Unknown connector: {connector_name}"}), 404
+
+    if not connector.validate_credentials():
+        return jsonify({"error": "Invalid credentials for connector"}), 401
+
+    # Parse optional date filters
+    since = None
+    until = None
+    try:
+        from datetime import date as date_cls
+        if data.get("since"):
+            since = date_cls.fromisoformat(data["since"])
+        if data.get("until"):
+            until = date_cls.fromisoformat(data["until"])
+    except ValueError as e:
+        return jsonify({"error": f"Invalid date format: {e}"}), 400
+
+    result = connector.refresh(account_id)
+    return jsonify(result.to_dict()), 200 if result.success else 500
+
+
+@bp.route("/bank-sync/balance", methods=["POST"])
+@jwt_required()
+def get_account_balance():
+    """Get current account balance via connector."""
+    data = request.get_json() or {}
+    connector_name = data.get("connector")
+    account_id = data.get("account_id", "default")
+    credentials = data.get("credentials", {})
+
+    if not connector_name:
+        return jsonify({"error": "connector name is required"}), 400
+
+    connector = create_connector(connector_name, credentials, data.get("options", {}))
+    if not connector:
+        return jsonify({"error": f"Unknown connector: {connector_name}"}), 404
+
+    cls = connector.__class__
+    if not cls.SUPPORTS_BALANCE:
+        return jsonify({
+            "error": f"Connector '{connector_name}' does not support balance queries"
+        }), 400
+
+    balance = connector.get_balance(account_id)
+    return jsonify({
+        "connector": connector_name,
+        "account_id": account_id,
+        "balance": str(balance) if balance is not None else None,
+        "currency": credentials.get("currency", "USD"),
+    }), 200