s3-npm-cache/lib/process.js

Lightweight runtime to cache NPM dependencies in S3

var s3 = require('./s3'),
    archive = require('./archive'),
    shell = require('shelljs'),
    fs = require('fs'),
    misc = require('./misc');

var pm = {};

var setProcessMetadata = function (metadata) {
    pm = metadata;
};

var npmAction = function (action) {
    shell.exec('cd ' + pm.packageJsonFileLocation + ' && npm ' + action);
};

var cleanup = function () {
    if (fs.existsSync(pm.s3PackageName)) {
        fs.unlinkSync(pm.s3PackageName);
    }
};

var unzipNodeModules = function (fileName) {
    console.log('Downloaded ZIP file from S3. Unzipping...');
    archive.unzip(fileName, pm.packageJsonFileLocation)
        .then(function () {
            console.log('NPM rebuilding...');
            npmAction('rebuild');

            console.log('Done!');
        })
        .catch(function (err) {
            console.error('Error unzipping', err);
        })
        .finally(cleanup);
};

var uploadNewFile = function (err) {
    if (err.code !== 'NoSuchKey') {
        console.warn('Error occurred attempting connection to S3', err);

        console.log('Npm installing...');
        npmAction('install');

        return;
    }

    console.log(pm.s3PackageName, 'not found . Npm installing...');
    npmAction('install');

    console.log('Node modules installed. Zipping...');
    archive.createZip(pm.nodeModulesFolder, pm.s3PackageName)
        .then(function () {
            console.log('Zip created. Uploading...');
            s3.uploadFileToS3(pm.s3PackageName)
                .then(function () {
                    console.log('Done!')
                })
                .catch(function (err) {
                    console.error('Failed to upload file :' + err);
                })
                .fin(cleanup);
        })
        .catch(function (err) {
            console.error('Error creating zip', err);
        });
};

module.exports = {
    unzipNodeModules: unzipNodeModules,
    uploadNewFile: uploadNewFile,
    setProcessMetadata: setProcessMetadata,
    npmAction: npmAction
};