Lightweight `qs.stringify` implementation

qs-stringify.lite.ts

/** Ref: https://github.com/suhaotian/xior/blob/main/src/utils.ts#L8 */ 

export function encodeParams<T = any>(
  params: T,
  encodeURI = true,
  parentKey: string | null = null,
  options?: {
    allowDots?: boolean;
    serializeDate?: (value: Date) => string;
    arrayFormat?: 'indices' | 'repeat' | 'brackets';
  }
): string {
  if (params === undefined || params === null) return '';
  const encodedParams = [];
  const encodeURIFn = encodeURI ? encodeURIComponent : (v: string) => v;
  const paramsIsArray = Array.isArray(params);
  const getKey = (key: string) => {
    if (options?.allowDots && !paramsIsArray) return `.${key}`;
    if (paramsIsArray) {
      if (options?.arrayFormat === 'brackets') {
        return `[]`;
      } else if (options?.arrayFormat === 'repeat') {
        return ``;
      }
    }
    return `[${key}]`;
  };
  for (const key in params) {
    if (Object.prototype.hasOwnProperty.call(params, key)) {
      let value = (params as any)[key];
      if (value !== undefinedValue) {
        const encodedKey = parentKey ? `${parentKey}${getKey(key)}` : (key as string);

        if (value instanceof Date) {
          value = options?.serializeDate ? options?.serializeDate(value) : value.toISOString();
        }
        if (typeof value === 'object') {
          // If the value is an object or array, recursively encode its contents
          const result = encodeParams(value, encodeURI, encodedKey, options);
          if (result !== '') encodedParams.push(result);
        } else {
          // Otherwise, encode the key-value pair
          encodedParams.push(`${encodeURIFn(encodedKey)}=${encodeURIFn(value)}`);
        }
      }
    }
  }

  return encodedParams.join('&');
}

Usage:

const query = {a: 1, b: [1, 2, 3], d: new Date()};
const result = encodeParams(query, true, null, {
  allowDots: false,
  arrayFormat: 'indices',
  serializeDate: d => d.toISOString()
})