@typedef `doGet`, `doPost` event parameter

[oshliaer]

/**
 * @typedef {Object} HTTPEvent
 * {@link https://developers.google.com/apps-script/guides/web Web Apps}
 * @property {string} queryString The value of the query string portion of
 *   the URL, or null if no query string is specified.
 * @property {object} parameter An object of key/value pairs that correspond to
 *   the request parameters.  Only the first value is returned for parameters
 *   that have multiple values.
 * @property {object} parameters An object similar to e.parameter, but with
 *   an array of values for each key.
 * @property {string} [contextPath=''] Not used, always the empty string.
 * @property {number} contentLength The length of the request body for
 *   POST requests, or -1 for GET requests.
 * @property {HTTPEventPostData} postData postData
 */

/**
 * @typedef {Object} HTTPEventPostData
 * @property {number} length The same as e.contentLength
 * @property {string} type The MIME type of the POST body
 * @property {string} contents The content text of the POST body
 * @property {string} postData Always the value "postData"
 */

/* exported doGet, doPost */
function doGet(e) {}

/**
 *
 * @param {HTTPEvent} e
 */
function doPost(e) {
  console.log(e.postData.contents);
  console.log(JSON.parse(e.postData.contents));
}

function example() {
  // Make a POST request with a JSON payload.
  var data = {
    name: 'Bob Smith',
    age: 35,
    pets: ['fido', 'fluffy']
  };
  var options = {
    method: 'post',
    contentType: 'application/json',
    // Convert the JavaScript object to a JSON string.
    payload: JSON.stringify(data)
  };
  UrlFetchApp.fetch('https://script.google.com/macros/s/xxx/exec', options);
}

[oshliaer]

// Type definitions for Google Apps Script 2019-04-02
// Project: https://developers.google.com/apps-script/
// Definitions by: grant <https://github.com/grant/>
// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped

/// <reference path="google-apps-script.script.d.ts" />
/// <reference path="google-apps-script.spreadsheet.d.ts" />
/// <reference path="google-apps-script.slides.d.ts" />

declare namespace GoogleAppsScript {
  /**
   * Google Apps Script Events
   * @see https://developers.google.com/apps-script/guides/triggers/events
   */
  export module Events {
    // Internal interfaces
    interface AppsScriptEvent {
      authMode: Script.AuthMode,
      triggerUid: string,
      user: Base.User,
    }

    interface HttpRequestEvent {
      parameter: object,
      contextPath: string,
      contentLength: number
      queryString: string,
      parameters: object,
    }

    /**
     * TODO: What about other properties?
     * copyBlob, getAllBlobs, getAs, getBlob, getBytes, getContentType,
     * getDataAsString, getDocId, getImageUrl, getName, getPrimitiveByteArray,
     * isGoogleType, requireContentType, requireData, requireName, setBytes,
     * setContentType, setContentTypeFromExtension, setDataFromString,
     * setDataFromString, setName, toString
     */
    interface HttpRequestEventPostData {
      length: number,
      type: string,
      contents: string,
      name: string // Always the value "postData"
    }

    // External interfaces
    export interface SheetsOnOpen extends AppsScriptEvent {
      source: Spreadsheet.Spreadsheet,
    }

    enum SheetsOnChangeChangeType { EDIT, INSERT_ROW, INSERT_COLUMN, REMOVE_ROW, REMOVE_COLUMN, INSERT_GRID, REMOVE_GRID, FORMAT, OTHER }
    export interface SheetsOnChange extends AppsScriptEvent {
      changeType: SheetsOnChangeChangeType,
    }

    export interface SheetsOnEdit extends AppsScriptEvent {
      oldValue: string,
      range: Spreadsheet.Range,
      source: Spreadsheet.Spreadsheet,
      value: string,
    }

    export interface FormsOnSubmit extends AppsScriptEvent {
      namedValues: { [key: string]: string[]; },
      range: Spreadsheet.Range,
      values: string[],
    }

    export interface DocsOnOpen extends AppsScriptEvent {
      source: Document.Document,
    }

    export interface SlidesOnOpen extends AppsScriptEvent {
      source: Slides.Presentation,
    }

    export interface FormsOnOpen extends AppsScriptEvent {
      source: Forms.Form,
    }

    // TODO: Is there a `user` attribute?
    export interface CalendarEventUpdated extends AppsScriptEvent {
      calendarId: string,
    }

    export interface AddonOnInstall {
      authMode: Script.AuthMode,
    }

    export interface DoGet extends HttpRequestEvent {
    }

    export interface DoPost extends HttpRequestEvent {
      postData: HttpRequestEventPostData
    }
  }
}

[oshliaer]

https://github.com/DefinitelyTyped/DefinitelyTyped/pull/35646