feat: truncate parsed uploads to prevent database and frontend blocking caused by excessively large files (#3914)

* 📝 (constants.ts): increase maxSizeFilesInBytes constant value from 10MB to 100MB to allow larger file uploads

* 🐛 (inputFileComponent): fix bug in setting the maximum file size alert message to display the correct file size limit of 100 bytes instead of 10 bytes

* 📝 (schemas.py): Add a new field_serializer method to serialize data in VertexBuildResponse class
📝 (schemas.py): Add a new truncate_text helper function to safely truncate text in nested dictionaries
📝 (model.py): Add a new field_serializer method to serialize outputs in TransactionBase class
📝 (model.py): Add a new truncate_text helper function to safely truncate text in nested dictionaries
📝 (model.py): Add a new field_serializer method to serialize data and artifacts in VertexBuildBase class
📝 (model.py): Add a new truncate_text helper function to safely truncate text in nested dictionaries

* 🐛 (schemas.py): fix truncation length of text fields to 10 characters instead of 99999
🐛 (model.py): fix truncation length of text fields to 10 characters instead of 99999
🐛 (model.py): fix truncation length of text fields to 10 characters instead of 99999
🐛 (index.tsx): truncate resultMessage to 99999 characters and add message if text is too long

* 🔧 (switchOutputView/index.tsx): Use useMemo to memoize resultMessage transformations for performance optimization

* 🐛 (model.py): Fix typo in the path for 'base_retriever' data field
🐛 (model.py): Fix typo in the path for 'base_retriever' data field
🐛 (model.py): Fix typo in the path for 'base_retriever' data field
🐛 (model.py): Fix typo in the path for 'base_retriever' data field
🐛 (index.tsx): Fix logic to correctly handle resultMessageMemoized when it is an object

* 📝 (model.py): refactor truncate_text function to truncate_long_strings for better clarity and consistency
📝 (model.py): update serialize_outputs and serialize_artifacts functions to use truncate_long_strings for string truncation
📝 (model.py): introduce MAX_TEXT_LENGTH constant for defining the maximum length of text to truncate in the models

* 📝 (schemas.py): refactor serialize_data method in VertexBuildResponse class to use a new helper function truncate_long_strings for better code readability and maintainability

* 🔧 (schemas.py): Move the `truncate_long_strings` function to a separate module to improve code organization and reusability
🔧 (model.py): Import the `truncate_long_strings` function from the correct module to fix the reference error
🔧 (model.py): Import the `truncate_long_strings` function from the correct module to fix the reference error

* 📝 (util.py): add function truncate_long_strings to recursively truncate long strings in dictionaries and lists to prevent exceeding the maximum text length.

* 📝 (constants.py): add constant MAX_TEXT_LENGTH with value 99999 for defining maximum text length allowed in the application

* 📝 (model.py): update import path for truncate_long_strings function to match new location in util module

* ✨ (test_truncate_long_strings_on_objects.py): Add unit tests for the function truncate_long_strings to ensure correct behavior when truncating long strings in various data structures
🐛 (switchOutputView/index.tsx): Fix truncation logic to correctly truncate long strings by adding ellipsis at the end instead of displaying additional text about truncation.

* [autofix.ci] apply automated fixes

* ✨ (test_truncate_long_strings_on_objects.py): Update import path for truncate_long_strings function
📝 (test_truncate_long_strings_on_objects.py): Add additional tests for handling negative, zero, and small max_length values in truncate_long_strings function

* ♻️ (schemas.py): refactor import statement to use the updated module name util_strings instead of util for better clarity and consistency.

* 📝 (model.py): Update import path for util_strings module to fix module import error
📝 (util.py): Remove redundant code for truncating long strings and move it to a separate util_strings module for better organization and separation of concerns.

* 📝 (schemas.py): refactor serialize_data method to handle both BaseModel and non-BaseModel data inputs in VertexBuildResponse class

* 📝 (util_strings.py): Update util_strings.py to improve string truncation function for dictionaries and lists
🔧 (test_truncate_long_strings_on_objects.py): Update test cases for string truncation function to cover additional scenarios and edge cases

* Update src/backend/base/langflow/utils/util_strings.py

Co-authored-by: Gabriel Luiz Freitas Almeida <gabriel@langflow.org>

* 📝 (vite.config.mts): update environment variable MAX_FILE_SIZE to be defined in vite config for frontend to use in the application.

* 📝 (constants.ts): update maxSizeFilesInBytes constant to use process.env.MAX_FILE_SIZE environment variable for configurable file size limit
📝 (constants.ts): add MAX_TEXT_LENGTH constant with a value of 99999 for maximum text length limit

* 📝 (switchOutputView/index.tsx): import MAX_TEXT_LENGTH constant from shared constants file to improve code organization and reusability

* ✨ (langflow/__main__.py): add support for defining maximum file size for upload in MB to improve user experience and prevent large file uploads

* 🐛 (files.py): add validation to check if uploaded file size exceeds the maximum allowed size before processing it

* ✨ (schemas.py): add max_file_size_upload field to ConfigResponse schema to handle maximum file size allowed for upload

* 🔧 (vite.config.mts): remove MAX_FILE_SIZE environment variable configuration as it is no longer needed

* ✨ (base.py): introduce max_file_size_upload setting to limit the file size for uploads in MB

* 🐛 (util.py): add support for setting max_file_size_upload in update_settings function to allow configuring maximum file size for uploads

* 📝 (inputFileComponent/index.tsx): add support for retrieving max file size upload from utility store to improve code modularity and reusability
🐛 (inputFileComponent/index.tsx): fix error handling logic to display error message when uploading a file fails

* 📝 (constants.ts): remove maxSizeFilesInBytes constant as it is no longer used and update MAX_TEXT_LENGTH constant to a higher value

* ✨ (use-get-config.ts): add functionality to set max file size upload value from config response

* ✨ (utilityStore.ts): introduce maxFileSizeUpload property and setMaxFileSizeUpload function to handle maximum file size upload in bytes

* ✨ (frontend): introduce maxFileSizeUpload property and setMaxFileSizeUpload method to handle maximum file size upload functionality in the UtilityStoreType

* ♻️ (util_strings.py): refactor truncate_long_strings function to improve code readability and consistency by removing unnecessary whitespace and aligning assignment operators.

* 🐛 (files.py): fix formatting issue in the raise statement to improve code readability and maintain consistency

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Gabriel Luiz Freitas Almeida <gabriel@langflow.org>

src/backend/tests/unit/utils/test_truncate_long_strings_on_objects.py

@@ -0,0 +1,98 @@
+from langflow.utils.util_strings import truncate_long_strings
+from langflow.utils.constants import MAX_TEXT_LENGTH
+import pytest
+
+
+@pytest.mark.parametrize(
+    "input_data, max_length, expected",
+    [
+        # Test case 1: Simple string truncation
+        ({"key": "a" * 100}, 10, {"key": "a" * 10 + "..."}),
+        # Test case 2: Nested dictionary
+        ({"outer": {"inner": "b" * 100}}, 5, {"outer": {"inner": "b" * 5 + "..."}}),
+        # Test case 3: List of strings
+        (["short", "a" * 100, "also short"], 7, ["short", "a" * 7 + "...", "also sh" + "..."]),
+        # Test case 4: Mixed nested structure
+        (
+            {"key1": ["a" * 100, {"nested": "b" * 100}], "key2": "c" * 100},
+            8,
+            {"key1": ["a" * 8 + "...", {"nested": "b" * 8 + "..."}], "key2": "c" * 8 + "..."},
+        ),
+        # Test case 5: Empty structures
+        ({}, 10, {}),
+        ([], 10, []),
+        # Test case 6: Strings at exact max_length
+        ({"exact": "a" * 10}, 10, {"exact": "a" * 10}),
+        # Test case 7: Non-string values
+        ({"num": 12345, "bool": True, "none": None}, 5, {"num": 12345, "bool": True, "none": None}),
+        # Test case 8: Unicode characters
+        ({"unicode": "こんにちは世界"}, 3, {"unicode": "こんに..."}),
+        # Test case 9: Very large structure
+        (
+            {"key" + str(i): "value" * i for i in range(1000)},
+            10,
+            {"key" + str(i): ("value" * i)[:10] + "..." if len("value" * i) > 10 else "value" * i for i in range(1000)},
+        ),
+    ],
+)
+def test_truncate_long_strings(input_data, max_length, expected):
+    result = truncate_long_strings(input_data, max_length)
+    assert result == expected
+
+
+def test_truncate_long_strings_default_max_length():
+    long_string = "a" * (MAX_TEXT_LENGTH + 1)
+    input_data = {"key": long_string}
+    result = truncate_long_strings(input_data)
+    assert len(result["key"]) == MAX_TEXT_LENGTH + 3  # +3 for the "..."
+
+
+def test_truncate_long_strings_no_modification():
+    input_data = {"short": "short string", "nested": {"also_short": "another short string"}}
+    result = truncate_long_strings(input_data, 100)
+    assert result == input_data
+
+
+# Test for type preservation
+def test_truncate_long_strings_type_preservation():
+    input_data = {"str": "a" * 100, "list": ["b" * 100], "dict": {"nested": "c" * 100}}
+    result = truncate_long_strings(input_data, 10)
+    assert isinstance(result, dict)
+    assert isinstance(result["str"], str)
+    assert isinstance(result["list"], list)
+    assert isinstance(result["dict"], dict)
+
+
+# Test for in-place modification
+def test_truncate_long_strings_in_place_modification():
+    input_data = {"key": "a" * 100}
+    result = truncate_long_strings(input_data, 10)
+    assert result is input_data  # Check if the same object is returned
+
+
+# Test for invalid input
+def test_truncate_long_strings_invalid_input():
+    input_string = "not a dict or list"
+    result = truncate_long_strings(input_string, 10)
+    assert result == input_string  # The function should return the input unchanged
+
+
+# Updated test for negative max_length
+def test_truncate_long_strings_negative_max_length():
+    input_data = {"key": "value"}
+    result = truncate_long_strings(input_data, -1)
+    assert result == input_data  # Assuming the function ignores negative max_length
+
+
+# Additional test for zero max_length
+def test_truncate_long_strings_zero_max_length():
+    input_data = {"key": "value"}
+    result = truncate_long_strings(input_data, 0)
+    assert result == {"key": "..."}  # Assuming the function truncates to just "..."
+
+
+# Test for very small positive max_length
+def test_truncate_long_strings_small_max_length():
+    input_data = {"key": "value"}
+    result = truncate_long_strings(input_data, 1)
+    assert result == {"key": "v..."}  # Assuming the function keeps at least one character