feat: Add LambdaFilter for enhanced data filtering (#7095)

* feat: add LambdaFilterComponent for dynamic data filtering

- Introduced LambdaFilterComponent to generate lambda functions for filtering or transforming structured data using LLMs.
- Updated __init__.py to include the new component.
- Added utility functions in data_structure.py for analyzing and inferring data types.
- Implemented unit tests for LambdaFilterComponent to ensure functionality and error handling.

* feat: enhance LambdaFilterComponent with new features and improvements

- Updated filter_instruction input to provide clearer guidance and examples.
- Added max_size input to specify character limits for large datasets.
- Renamed output from "Processed Data" to "Filtered Data" for clarity.
- Introduced new output "DataFrame" to return filtered data in DataFrame format.
- Improved data handling in filter_data method to ensure proper conversion of processed data to Data objects.
- Added as_dataframe method to return filtered data as a DataFrame.

This update enhances usability and functionality of the LambdaFilterComponent.

* [autofix.ci] apply automated fixes

* fix: ruff errors

* [autofix.ci] apply automated fixes

* [autofix.ci] apply automated fixes (attempt 2/3)

* [autofix.ci] apply automated fixes (attempt 3/3)

* [autofix.ci] apply automated fixes

* updated the test file and fixed formatting issues

* [autofix.ci] apply automated fixes

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: italojohnny <italojohnnydosanjos@gmail.com>
Co-authored-by: Edwin Jose <edwin.jose@datastax.com>

src/backend/tests/unit/components/processing/test_lambda_filter.py

@@ -0,0 +1,122 @@
+from unittest.mock import AsyncMock
+
+import pytest
+from langflow.components.processing.lambda_filter import LambdaFilterComponent
+from langflow.schema import Data
+
+from tests.base import ComponentTestBaseWithoutClient
+
+
+class TestLambdaFilterComponent(ComponentTestBaseWithoutClient):
+    @pytest.fixture
+    def component_class(self):
+        return LambdaFilterComponent
+
+    @pytest.fixture
+    def default_kwargs(self):
+        return {
+            "data": [Data(data={"items": [{"name": "test1", "value": 10}, {"name": "test2", "value": 20}]})],
+            "llm": AsyncMock(),
+            "filter_instruction": "Filter items with value greater than 15",
+            "sample_size": 1000,
+            "max_size": 30000,
+        }
+
+    @pytest.fixture
+    def file_names_mapping(self):
+        return []
+
+    async def test_successful_lambda_generation(self, component_class, default_kwargs):
+        component = await self.component_setup(component_class, default_kwargs)
+        component.llm.ainvoke.return_value.content = "lambda x: [item for item in x['items'] if item['value'] > 15]"
+
+        # Execute filter
+        result = await component.filter_data()
+
+        # Assertions
+        assert isinstance(result, list)
+        assert len(result) == 1
+        assert result[0].name == "test2"
+        assert result[0].value == 20
+
+    async def test_invalid_lambda_response(self, component_class, default_kwargs):
+        component = await self.component_setup(component_class, default_kwargs)
+        component.llm.ainvoke.return_value.content = "invalid lambda syntax"
+
+        # Test exception handling
+        with pytest.raises(ValueError, match="Could not find lambda in response"):
+            await component.filter_data()
+
+    async def test_lambda_with_large_dataset(self, component_class, default_kwargs):
+        large_data = {"items": [{"name": f"test{i}", "value": i} for i in range(2000)]}
+        default_kwargs["data"] = [Data(data=large_data)]
+        default_kwargs["filter_instruction"] = "Filter items with value greater than 1500"
+        component = await self.component_setup(component_class, default_kwargs)
+        component.llm.ainvoke.return_value.content = "lambda x: [item for item in x['items'] if item['value'] > 1500]"
+
+        # Execute filter
+        result = await component.filter_data()
+
+        # Assertions
+        assert isinstance(result, list)
+        assert len(result) == 499  # Items with value from 1501 to 1999
+        assert all(item.value > 1500 for item in result)
+
+    async def test_lambda_with_complex_data_structure(self, component_class, default_kwargs):
+        complex_data = {
+            "categories": {
+                "A": [{"id": 1, "score": 90}, {"id": 2, "score": 85}],
+                "B": [{"id": 3, "score": 95}, {"id": 4, "score": 88}],
+            }
+        }
+        default_kwargs["data"] = [Data(data=complex_data)]
+        default_kwargs["filter_instruction"] = "Filter items with score greater than 90"
+        component = await self.component_setup(component_class, default_kwargs)
+        component.llm.ainvoke.return_value.content = (
+            "lambda x: [item for cat in x['categories'].values() for item in cat if item['score'] > 90]"
+        )
+
+        # Execute filter
+        result = await component.filter_data()
+
+        # Assertions
+        assert isinstance(result, list)
+        assert len(result) == 1
+        assert result[0].id == 3
+        assert result[0].score == 95
+
+    def test_validate_lambda(self, component_class):
+        component = component_class()
+
+        # Valid lambda
+        valid_lambda = "lambda x: x + 1"
+        assert component._validate_lambda(valid_lambda) is True
+
+        # Invalid lambda: missing 'lambda'
+        invalid_lambda_1 = "x: x + 1"
+        assert component._validate_lambda(invalid_lambda_1) is False
+
+        # Invalid lambda: missing ':'
+        invalid_lambda_2 = "lambda x x + 1"
+        assert component._validate_lambda(invalid_lambda_2) is False
+
+    def test_get_data_structure(self, component_class):
+        component = component_class()
+        test_data = {
+            "string": "test",
+            "number": 42,
+            "list": [1, 2, 3],
+            "dict": {"key": "value"},
+            "nested": {"a": [{"b": 1}]},
+        }
+
+        structure = component.get_data_structure(test_data)
+
+        # Assertions
+        assert structure["string"]["structure"] == "str"
+        assert structure["number"]["structure"] == "int"
+        assert structure["list"]["structure"] == "list(int)[size=3]"
+        assert structure["dict"]["structure"]["key"] == "str"
+        assert "structure" in structure["nested"]
+        assert "a" in structure["nested"]["structure"]
+        assert "list" in structure["nested"]["structure"]["a"]