/// <reference types="node" />
import * as childProcess from 'child_process';
import { JsonObject } from './utils/http_utils';
import { ProviderClass, ProviderConfig, ProviderInterface } from './provider';
export declare class Chromium extends ProviderClass implements ProviderInterface {
    cacheFileName: string;
    cacheVersionFileName: string;
    cacheStorageFileName: string;
    compressedBinaryFileName: string;
    configFileName: string;
    ignoreSSL: boolean;
    osType: string;
    osArch: string;
    outDir: string;
    proxy: string;
    maxVersion: string;
    constructor(config?: ProviderConfig);
    private makeDirectory;
    /**
     * Step 1: Download the json file that contains all the releases by OS. Each
     * OS will have a list of release versions. The requested body will also be
     * written to the out directory.
     *
     * The requested url is https://omahaproxy.appspot.com/all.json. Some other
     * urls include a timestamped csv https://omahaproxy.appspot.com/history.
     * @return Promise of the all-json file.
     */
    downloadAllJson(): Promise<JsonObject>;
    /**
     * Step 2: From the all-json object, make a request that matches the major
     * version requested. The requested body will also be written to file in the
     * out directory.
     *
     * An example of a requsted url is
     * https://omahaproxy.appspot.com/deps.json?version=72.0.3626.81
     * @param allJson The all-json object.
     * @param majorVersion The major version, this must be a whole number.
     */
    downloadVersionJson(allJson: JsonObject, majorVersion: string): Promise<JsonObject>;
    /**
     * Step 3: From the downloaded-version-json object, get the revision number.
     * This is the "chromium_base_position" and make a request to the storage
     * bucket. If the returned value is {"kind": "storage#objects"}, then
     * decrement the revision number.
     *
     * An example is the chromium_base_position revision number (612437).
     * https://www.googleapis.com/storage/v1/b/chromium-browser-snapshots/o?delimiter=/&prefix=Linux_x64/612437/
     * returns {"kind": "storage#objects"}.
     *
     * We keep decrementing the number until we reach 612434 where there is a list
     * of items.
     * @param downloadJson The download-version-json object.
     * @param majorVersion The major version, this must be a whole number.
     */
    downloadStorageObject(downloadJson: JsonObject, majorVersion: string): Promise<JsonObject>;
    /**
     * Step 4: Get the download url for the chromium zip. Unzipping the zip file
     * directory. The folders and binaries uncompressed are different for each OS.
     * The following is examples of each OS:
     *
     * downloads/
     *  |- chrome-linux/chrome
     *  |- chrome-mac/Chromium.app
     *  |- chrome-win/chrome.exe
     *
     * @param storageObject The download-storage-json object
     * @param majorVersion The major version, this must be a whole number.
     */
    downloadUrl(storageObject: JsonObject, majorVersion: string): Promise<void>;
    updateBinary(_: string, majorVersion?: string): Promise<void>;
    getBinaryPath(version?: string): string | null;
    getStatus(): string | null;
    cleanFiles(): string;
}
/**
 * Helps translate the os type and arch to the download name associated
 * with composing the download link.
 * @param ostype The operating stystem type.
 * @param osarch The chip architecture.
 * @returns The download name associated with composing the download link.
 */
export declare function osHelper(ostype: string, osarch: string): string;
/**
 * A command line to run. Example 'npm start', the task='npm' and the
 * opt_arg=['start']
 * @param task The task string.
 * @param optArg Optional task args.
 * @param optIo Optional io arg. By default, it should log to console.
 * @returns The child process.
 */
export declare function spawnProcess(task: string, optArg?: string[], optIo?: string): childProcess.SpawnSyncReturns<Buffer>;