check-disk-space.mjs

import { execFile } from 'node:child_process';
import { access } from 'node:fs/promises';
import { release } from 'node:os';
import { normalize, sep } from 'node:path';
import { platform } from 'node:process';
import { promisify } from 'node:util';

class InvalidPathError extends Error {
    constructor(message) {
        super(message);
        this.name = 'InvalidPathError';
        // Set the prototype explicitly.
        Object.setPrototypeOf(this, InvalidPathError.prototype);
    }
}

class NoMatchError extends Error {
    constructor(message) {
        super(message);
        this.name = 'NoMatchError';
        // Set the prototype explicitly.
        Object.setPrototypeOf(this, NoMatchError.prototype);
    }
}

/**
 * Tells if directory exists
 *
 * @param directoryPath - The file/folder path
 * @param dependencies - Dependencies container
 */
async function isDirectoryExisting(directoryPath, dependencies) {
    try {
        await dependencies.fsAccess(directoryPath);
        return Promise.resolve(true);
    }
    catch (error) {
        return Promise.resolve(false);
    }
}

/**
 * Get the first existing parent path
 *
 * @param directoryPath - The file/folder path from where we want to know disk space
 * @param dependencies - Dependencies container
 */
async function getFirstExistingParentPath(directoryPath, dependencies) {
    let parentDirectoryPath = directoryPath;
    let parentDirectoryFound = await isDirectoryExisting(parentDirectoryPath, dependencies);
    while (!parentDirectoryFound) {
        parentDirectoryPath = dependencies.pathNormalize(parentDirectoryPath + '/..');
        parentDirectoryFound = await isDirectoryExisting(parentDirectoryPath, dependencies);
    }
    return parentDirectoryPath;
}

/**
 * Tell if PowerShell 3 is available based on Windows version
 *
 * Note: 6.* is Windows 7
 * Note: PowerShell 3 is natively available since Windows 8
 *
 * @param dependencies - Dependencies Injection Container
 */
async function hasPowerShell3(dependencies) {
    const major = parseInt(dependencies.release.split('.')[0], 10);
    if (major <= 6) {
        return false;
    }
    try {
        await dependencies.cpExecFile('where', ['powershell'], { windowsHide: true });
        return true;
    }
    catch (error) {
        return false;
    }
}

/**
 * Check disk space
 *
 * @param directoryPath - The file/folder path from where we want to know disk space
 * @param dependencies - Dependencies container
 */
function checkDiskSpace(directoryPath, dependencies = {
    platform,
    release: release(),
    fsAccess: access,
    pathNormalize: normalize,
    pathSep: sep,
    cpExecFile: promisify(execFile),
}) {
    // Note: This function contains other functions in order
    //       to wrap them in a common context and make unit tests easier
    /**
     * Maps command output to a normalized object {diskPath, free, size}
     *
     * @param stdout - The command output
     * @param filter - To filter drives (only used for win32)
     * @param mapping - Map between column index and normalized column name
     * @param coefficient - The size coefficient to get bytes instead of kB
     */
    function mapOutput(stdout, filter, mapping, coefficient) {
        const parsed = stdout
            .split('\n') // Split lines
            .map(line => line.trim()) // Trim all lines
            .filter(line => line.length !== 0) // Remove empty lines
            .slice(1) // Remove header
            .map(line => line.split(/\s+(?=[\d/])/)); // Split on spaces to get columns
        const filtered = parsed.filter(filter);
        if (filtered.length === 0) {
            throw new NoMatchError();
        }
        const diskData = filtered[0];
        return {
            diskPath: diskData[mapping.diskPath],
            free: parseInt(diskData[mapping.free], 10) * coefficient,
            size: parseInt(diskData[mapping.size], 10) * coefficient,
        };
    }
    /**
     * Run the command and do common things between win32 and unix
     *
     * @param cmd - The command to execute
     * @param filter - To filter drives (only used for win32)
     * @param mapping - Map between column index and normalized column name
     * @param coefficient - The size coefficient to get bytes instead of kB
     */
    async function check(cmd, filter, mapping, coefficient = 1) {
        const [file, ...args] = cmd;
        /* istanbul ignore if */
        if (file === undefined) {
            return Promise.reject(new Error('cmd must contain at least one item'));
        }
        try {
            const { stdout } = await dependencies.cpExecFile(file, args, { windowsHide: true });
            return mapOutput(stdout, filter, mapping, coefficient);
        }
        catch (error) {
            return Promise.reject(error);
        }
    }
    /**
     * Build the check call for win32
     *
     * @param directoryPath - The file/folder path from where we want to know disk space
     */
    async function checkWin32(directoryPath) {
        if (directoryPath.charAt(1) !== ':') {
            return Promise.reject(new InvalidPathError(`The following path is invalid (should be X:\\...): ${directoryPath}`));
        }
        const powershellCmd = [
            'powershell',
            'Get-CimInstance -ClassName Win32_LogicalDisk | Select-Object Caption, FreeSpace, Size',
        ];
        const wmicCmd = [
            'wmic',
            'logicaldisk',
            'get',
            'size,freespace,caption',
        ];
        const cmd = await hasPowerShell3(dependencies) ? powershellCmd : wmicCmd;
        return check(cmd, driveData => {
            // Only get the drive which match the path
            const driveLetter = driveData[0];
            return directoryPath.toUpperCase().startsWith(driveLetter.toUpperCase());
        }, {
            diskPath: 0,
            free: 1,
            size: 2,
        });
    }
    /**
     * Build the check call for unix
     *
     * @param directoryPath - The file/folder path from where we want to know disk space
     */
    async function checkUnix(directoryPath) {
        if (!dependencies.pathNormalize(directoryPath).startsWith(dependencies.pathSep)) {
            return Promise.reject(new InvalidPathError(`The following path is invalid (should start by ${dependencies.pathSep}): ${directoryPath}`));
        }
        const pathToCheck = await getFirstExistingParentPath(directoryPath, dependencies);
        return check([
            'df',
            '-Pk',
            '--',
            pathToCheck,
        ], () => true, // We should only get one line, so we did not need to filter
        {
            diskPath: 5,
            free: 3,
            size: 1,
        }, 1024);
    }
    // Call the right check depending on the OS
    if (dependencies.platform === 'win32') {
        return checkWin32(directoryPath);
    }
    return checkUnix(directoryPath);
}

export { InvalidPathError, NoMatchError, checkDiskSpace as default, getFirstExistingParentPath };