parseLargeFields
The parseLargeFields function is a utility for truncating large string fields in JSON data to a specified maximum length. This function is particularly useful for logging, debugging, or displaying JSON data where extremely long string values might cause performance issues or clutter the output.
Import
import { parseLargeFields } from "@arkyn/shared";
Parameters
The function accepts the following parameters:
jsonString (required)
The JSON string to process. This should be a valid JSON string that can be parsed into a JavaScript object or array. The function will traverse the entire structure recursively to find and truncate long string values.
Type: string
maxLength (optional)
The maximum allowed length for string fields. Any string field that exceeds this length will be replaced with a message indicating the original length of the field. This helps identify truncated fields while keeping the output manageable.
Type: number
Default: 1000
Usage example
The function returns a JSON string with large string fields truncated. Truncated fields are replaced with the message "To large information: field as X characters", where X is the original length of the string.
Type: string
import { parseLargeFields } from "@arkyn/shared";
const json = JSON.stringify({
name: "John",
description:
"A very long description that exceeds the maximum length and needs to be truncated for display purposes",
});
const result = parseLargeFields(json, 50);
console.log(result);
Errors
The function performs validation and may throw an error in the following scenario:
Invalid JSON string: An error is thrown when the input string cannot be parsed as valid JSON. This includes malformed JSON such as missing quotes, trailing commas, unclosed brackets, or invalid syntax.
Notes
The function uses a recursive approach to traverse nested objects and arrays, ensuring that all string fields at any depth are checked and truncated if necessary.
Non-string values (numbers, booleans, null, etc.) are preserved as-is and are not affected by the truncation logic.
The truncation message includes the original character count, which can be useful for determining if you need to adjust the maxLength parameter or investigate specific fields.
Empty strings and strings shorter than or equal to maxLength are preserved unchanged.
The function works with complex nested structures including arrays of objects, objects with nested objects, and mixed data types.
