@micro-app/cli/src/utils/symlink/create.js

[CLI] Pluggable micro application framework.

'use strict';

const cmdShim = require('@zkochan/cmd-shim');
const { path, logger, fs } = require('@micro-app/shared-utils');

module.exports = createSymlink;

function createSymlink(src, dest, type) {
    logger.silly('createSymlink', [ src, dest, type ]);

    if (process.platform === 'win32') {
        return createWindowsSymlink(src, dest, type);
    }

    return createPosixSymlink(src, dest, type);
}

function createSymbolicLink(src, dest, type) {
    logger.silly('createSymbolicLink', [ src, dest, type ]);

    return fs
        .lstat(dest)
        .then(() => fs.unlink(dest))
        .catch(() => {
            /* nothing exists at destination */
        })
        .then(() => fs.symlink(src, dest, type));
}

function createPosixSymlink(src, dest, _type) {
    const type = _type === 'exec' ? 'file' : _type;
    const relativeSymlink = path.relative(path.dirname(dest), src);

    if (_type === 'exec') {
    // If the src exists, create a real symlink.
    // If the src doesn't exist yet, create a shim shell script.
        return fs.pathExists(src).then(exists => {
            if (exists) {
                return createSymbolicLink(relativeSymlink, dest, type).then(() => fs.chmod(src, 0o755));
            }

            return shShim(src, dest, type).then(() => fs.chmod(dest, 0o755));
        });
    }

    return createSymbolicLink(relativeSymlink, dest, type);
}

function createWindowsSymlink(src, dest, type) {
    if (type === 'exec') {
    // If the src exists, shim directly.
    // If the src doesn't exist yet, create a temp src so cmd-shim doesn't explode.
        return fs.pathExists(src).then(exists => {
            if (exists) {
                return cmdShim(src, dest);
            }

            return fs
                .outputFile(src, '')
                .then(() => cmdShim(src, dest))
                .then(
                    // fs.remove() never rejects
                    () => fs.remove(src),
                    err =>
                        fs.remove(src).then(() => {
                            // clean up, but don't swallow error
                            throw err;
                        })
                );
        });
    }

    return createSymbolicLink(src, dest, type);
}

function shShim(src, dest, type) {
    logger.silly('shShim', [ src, dest, type ]);

    const absTarget = path.resolve(path.dirname(dest), src);
    const scriptLines = [ '#!/bin/sh', `chmod +x ${absTarget} && exec ${absTarget} "$@"` ];

    return fs.writeFile(dest, scriptLines.join('\n'));
}