process-params.ts

/* Copyright (c) 2017 Environmental Systems Research Institute, Inc.
 * Apache-2.0 */

/**
 * Checks parameters to see if we should use FormData to send the request
 * @param params The object whose keys will be encoded.
 * @return A boolean indicating if FormData will be required.
 */
export function requiresFormData(params: any) {
  return Object.keys(params).some(key => {
    let value = params[key];

    if (!value) {
      return false;
    }

    if (value && value.toParam) {
      value = value.toParam();
    }

    const type = value.constructor.name;

    switch (type) {
      case "Array":
        return false;
      case "Object":
        return false;
      case "Date":
        return false;
      case "Function":
        return false;
      case "Boolean":
        return false;
      case "String":
        return false;
      case "Number":
        return false;
      default:
        return true;
    }
  });
}

/**
 * Converts parameters to the proper representation to send to the ArcGIS REST API.
 * @param params The object whose keys will be encoded.
 * @return A new object with properly encoded values.
 */
export function processParams(params: any): any {
  const newParams: any = {};

  Object.keys(params).forEach(key => {
    let param = params[key];

    if (param && param.toParam) {
      param = param.toParam();
    }

    if (
      !param &&
      param !== 0 &&
      typeof param !== "boolean" &&
      typeof param !== "string"
    ) {
      return;
    }

    const type = param.constructor.name;

    let value: any;

    // properly encodes objects, arrays and dates for arcgis.com and other services.
    // ported from https://github.com/Esri/esri-leaflet/blob/master/src/Request.js#L22-L30
    // also see https://github.com/Esri/arcgis-rest-js/issues/18:
    // null, undefined, function are excluded. If you want to send an empty key you need to send an empty string "".
    switch (type) {
      case "Array":
        // Based on the first element of the array, classify array as an array of arrays, an array of objects
        // to be stringified, or an array of non-objects to be comma-separated
        // eslint-disable-next-line no-case-declarations
        const firstElementType = param[0]?.constructor?.name;
        value =
          firstElementType === "Array" ? param : // pass thru array of arrays
          firstElementType === "Object" ? JSON.stringify(param) : // stringify array of objects
          param.join(","); // join other types of array elements
        break;
      case "Object":
        value = JSON.stringify(param);
        break;
      case "Date":
        value = param.valueOf();
        break;
      case "Function":
        value = null;
        break;
      case "Boolean":
        value = param + "";
        break;
      default:
        value = param;
        break;
    }
    if (value || value === 0 || typeof value === "string" || Array.isArray(value)) {
      newParams[key] = value;
    }
  });

  return newParams;
}