Feature: Output the SQL for the ran operation (--dump-sql)

[OsoianMarcel]

Would be great to have an option that will allow us too see the SQL before sequelize-cli will execute it. Because it's a little tricky to run sequelize-cli on production without checking the SQL output before execution.

--dump-sql option that will output the SQL for the ran operation.

Example: node_modules/.bin/sequelize db:migrate --dump-sql

Inspiration: Doctrine (search for "--dump-sql")

[ALiangLiang]

I think we need to mock or refactor QueryInterface to output the query string instead of execute on migration and seed.

Add dryRun option to QueryInterface and its each methods.

I design a flow to return query string from QueryInterface.[methods] but it cannot execute code to Query.run. If I interrupt on Query.run, It cannot response any result back.

sequelize-cli/src/core/migrator.js:

// ...

export function getMigrator (type, args) {
  return Bluebird.try(() => {
    if (!(helpers.config.configFileExists() || args.url)) {
      helpers.view.error(
        'Cannot find "' + helpers.config.getConfigFile() +
        '". Have you run "sequelize init"?'
      );
      process.exit(1);
    }

    const sequelize = getSequelizeInstance();
    const migrator = new Umzug({
      storage: helpers.umzug.getStorage(type),
      storageOptions: helpers.umzug.getStorageOptions(type, { sequelize }),
      logging: helpers.view.log,
      migrations: {

        // pass options to sequelize.getQueryInterface
        params: [sequelize.getQueryInterface({ dryRun: args.dryRun }), Sequelize],

        path: helpers.path.getPath(type),
        pattern: /\.js$/,
        wrap: fun => {
          if (fun.length === 3) {
            return Bluebird.promisify(fun);
          } else {
            return fun;
          }
        }
      }
    });

//...

sequelize/lib/sequelize.js:

// ...

  getQueryInterface(options) {
    // pass options to QueryInterface constructor
    this.queryInterface = this.queryInterface || new QueryInterface(this, options);
    return this.queryInterface;
  }

// ...

sequelize/lib/query-interface.js:

class QueryInterface {
  constructor(sequelize, options) {
    this.sequelize = sequelize;
    this.QueryGenerator = this.sequelize.dialect.QueryGenerator;
    this.options = _.extend({
      dryRun: false
    }, options || {});
  }

// ...

  renameTable(before, after, options) {
    // Accpet object-scoped options 
    // options => this.options => (default options)
    options = _.extend({
      logging: console.log,
      plain: false,
      raw: false,
      showWarnings: false
    }, this.options, options || {});

    const sql = this.QueryGenerator.renameTableQuery(before, after);
    if (options.dryRun) {
      return sql;
    } else {
      return this.sequelize.query(sql, options);
    }
  }

// ...

BTW. Maybe named --dry-run? I think developers are more familiar with it.

[OsoianMarcel]

@ALiangLiang you are right --dry-run it's a good option name.

[ALiangLiang]

similar #219

[frederikhors]

Please any news on this?

[AbrahamMunguia]

Have this been forgotten?