divshot-cli/lib/commands/migrate.js

CLI for Divshot

var chalk = require('chalk');
var _ = require('lodash');
var path = require('path');
var fs = require('fs');
var promptly = require('promptly');
var async = require('async');

var divshot2Firebase = function(source) {
  var warnings = [];
  var actions = [];
  var out = {};
  var data = {};
  var track = {};

  out.firebase = source.name;
  out.public = source.root || ".";
  if (source.exclude) {
    out.ignore = source.exclude;
  } else {
    out.ignore = ["firebase.json","**/.*","**/node_modules/**"]
  }

  if (source.clean_urls) {
    warnings.push(chalk.bold("clean_urls") + " support is planned for Firebase Hosting, but is not yet available");
    track.clean_urls = true;
  }
  if (source.error_page && source.error_page !== '404.html')
    actions.push("Rename " + chalk.bold(source.error_page) + " to " + chalk.bold("404.html"));
  if (source.proxy) {
    warnings.push("Firebase Hosting does not support AJAX proxying");
    track.ajax_proxy = true;
  }
  if (source.forms) {
    warnings.push("Firebase Hosting does not support form-to-email");
    track.forms = true;
  }
  if (source.prerender) {
    warnings.push("Firebase Hosting does not presently support JS prerendering");
    track.prerender = true;
  }
  if (fs.existsSync('.env.json')) {
    warnings.push("Firebase Hosting does not support JS environment variables");
    track.env = true;
  }

  if (_.isObject(source.routes)) {
    source.routes = [source.routes];
  }
  _.forEach(source.routes || [], function(routeObject) {
    _.forEach(routeObject, function(val, key) {
      out.rewrites = out.rewrites || [];
      out.rewrites.push({
        source: key,
        destination: path.normalize('/' + val)
      });
    });
  });

  if (_.isObject(source.redirects)) {
    source.redirects = [source.redirects];
  }
  _.forEach(source.redirects || [], function(redirectObject) {
    _.forEach(redirectObject, function(val, key) {
      out.redirects = out.redirects || [];

      if (_.isString(val)) {
        var obj = {
          source: key,
          destination: val,
          type: 301
        };
      } else {
        var obj = {
          source: key,
          destination: val.url,
          type: val.status
        }
      }

      if (_.contains(key, ':')) {
        warnings.push('Redirect for ' + chalk.bold(key) + ' contains path segments. This is not yet supported by Firebase Hosting.');
        track.redirect_segments = true;
      }

      out.redirects.push(obj);
    });
  });

  _.forEach(source.headers || {}, function(val, key) {
    var obj = {source: key, headers: []};
    _.forEach(val || {}, function(headerVal, headerKey) {
      if (_.contains([
        'Cache-Control',
        'Access-Control-Allow-Origin',
        'X-UA-Compatible',
        'X-Content-Type-Options',
        'X-Frame-Options',
        'X-XSS-Protection'
      ])) {
        obj.headers.push({key: headerKey, value: headerVal});
      } else {
        warnings.push('The ' + chalk.bold(headerKey) + ' header is not allowed by Firebase Hosting.');
        track.invalid_header = true;
      }
    });

    out.headers = out.headers || [];
    out.headers.push(obj);
  });

  _.forEach(source.cache_control || {}, function(val, key) {
    out.headers = out.headers || [];
    var outVal;
    if (_.isNumber(val)) {
      outVal = 'public, max-age=' + val.toString();
    } else if (_.isString(val)) {
      outVal = val;
    }

    if (outVal) {
      out.headers.push({
        source: key,
        headers: [{key: 'Cache-Control', value: outVal}]
      });
    }
  });

  return {
    warnings: warnings,
    actions: actions,
    track: track,
    output: out
  }
}

module.exports = function (cli) {
  cli.command('migrate')
    .description('migrate a Divshot app to Firebase Hosting')
    .handler(function (done) {
      var divshotConfigPath = path.resolve('divshot.json');
      var firebaseConfigPath = path.resolve('firebase.json');

      if (!fs.existsSync(divshotConfigPath)) {
        return done("Couldn't find divshot.json. Please run in a Divshot app dierctory.");
      }
      if (fs.existsSync(firebaseConfigPath)) {
        return done("Can't proceed, there is already a firebase.json in this directory.");
      }

      var source = require(divshotConfigPath);
      var result = divshot2Firebase(source);

      console.log();
      console.log(chalk.underline('Migrating Divshot app ' + chalk.bold(source.name) + ' to Firebase Hosting'));
      console.log();

      async.series({
        firebase: function(callback) {
          promptly.prompt('What is your Firebase project\'s name? (' + result.output.firebase + ') ', { default: result.output.firebase, }, callback)
        },
        track: function(callback) {
          promptly.confirm('Can we anonymously report which features your app used (for Firebase Hosting roadmap planning, etc.)? (y/n)', callback);
        },
        write: function(callback) {
          promptly.confirm('Write firebase.json? (y/n)', callback);
        }
      }, function(err, inputs) {
        var warningSign = process.platform === 'win32' ? '!' : '⚠';

        if (result.warnings.length) {
          console.log();
          console.log(chalk.yellow.bold.underline(warningSign + ' Warning: The following incompatible features were detected.'));
          _.forEach(result.warnings, function(warning) {
            console.log('- ' + warning);
          });
          console.log();
          console.log('  ' + chalk.bold("Don't panic!"), "Some features may be coming soon or there may be workarounds.\n  Contact", chalk.bold.underline("support@firebase.com"), "with any questions.");
        }

        if (result.actions.length) {
          console.log();
          console.log(chalk.cyan.bold.underline('You need to take the following actions to fully migrate your app:'));
          _.forEach(result.actions, function(action) {
            console.log('- ' + action);
          });
        }

        result.output.firebase = inputs.firebase;
        if (inputs.write) {
          fs.writeFileSync(firebaseConfigPath, JSON.stringify(result.output, null, 2), 'utf-8');
          console.log();
          console.log(chalk.green('Wrote firebase.json configuration file.'));
        }

        console.log();
        console.log('If you have the latest version of ' + chalk.bold('firebase-tools') + ' you should now be able');
        console.log('to run ' + chalk.bold('firebase serve') + ' in this directory to start a local server and');
        console.log(chalk.bold('firebase deploy') + ' to deploy to Firebase Hosting.');
        console.log();
        console.log('See ' + chalk.bold.underline('http://docs.divshot.com/migrate') + ' for additional migration info.');
        console.log();

        if (inputs.track) {
          var mixpanel = require('mixpanel').init('df1a3bd1b07c3caa45a6ea4fd0f163f1');
          mixpanel.track('Firebase Migration', result.track, function(err) {
            done();
          });
        } else {
          done();
        }
      });
    });
};