Pretty useful when writing scripts to initialize database for fresh install or dropping / creating new database when running tests and for truncating database between tests.

Library uses knex connection for non administrative queries, but also creates priviliged connection directly with driver with superuser privileges for creating and dropping databases / roles.

Supported Databases

• PostgreSQL
• MySQL
• SQLite3 (TBD even though most of the functions won't make sense with this)
• Oracle DB Express (TBD)
• MSSQL (TBD if we can get integration tests to run automatically)

Install

You need to install knex, database driver and knex-db-manager

npm install knex-db-manager knex pg pg-escape

API & Usage

Database manager is initialized with normal knex configuration and with superuser account which should be able to create / drop roles and databases.

Initialization:

let config = {
  knex: {
    // just the usual knex configuration
    client: 'postgres',
    connection: {
      host: 'localhost',
      database: 'appdb',
      user: 'dbowneruser',
      password: 'dbownerpassword'
    },
    pool: {
      min: 0,
      max: 10
    },
    migrations: {
      directory: __dirname + '/migrations'
    }
  },
  dbManager: {
    // db manager related configuration
    collate: ['fi_FI.UTF-8', 'Finnish_Finland.1252'],
    superUser: 'userwithrightstocreateusersanddatabases',
    superPassword: 'privilegeduserpassword'
  }
};

let dbManager = require('knex-db-manager').databaseManagerFactory(config);

createDbOwnerIfNotExist(): Promise<void>

Creates the user, which is described in knex configuration. This user is used as the database owner when creating new databases.

let promise = dbManager.createDbOwnerIfNotExist();

createDb(dbName?: string): Promise<void>

Creates database described in knex configuration or by given name. Owner of the created database is set to be the config.knex.connection.user.

dbName is the name of the database to be created, if not given the name is read from config.knex.connection.database.

Read database from config.knex.connection.database:

let promise = dbManager.createDb();

By given name:

let promise = dbManager.createDb('brave-new-db');

dropDb(dbName?: string): Promise<void>

Drops database described in knex configuration or by given name. Note that if there are any active connections to the database that is being dropped, the drop command might fail.

dbName is the name of the database to be dropped, if not given the name is read from config.knex.connection.database.

Drop database config.knex.connection.database:

let promise = dbManager.dropDb();

By specific name:

let promise = dbManager.dropDb('brave-new-db');

copyDb(fromDbName: string, toDbName: string): Promise<void>

Clones database to another name remotely on db serverside (may be useful e.g. to make backup before running migrations).

New database toDatabaseName will be created containing a copy of fromDbName.

Note: This method is not supported with MySQL (yet).

Making copy of DB:

let promise = dbManager.copyDb('brave-new-db', 'brave-new-db-copy');

truncateDb(ignoreTables?: string[]): Promise<void>

Truncate tables of the database and reset corresponding id sequences.

ignoreTables list of tables names which should not be truncated.

Truncate database config.knex.connection.database:

let promise = dbManager.truncateDb();

ignore certain tables:

let promise = dbManager.truncateDb(['migrations']);

updateIdSequences(): Promise<void>

Updates all primary key id sequences to be biggest id in table + 1. So after running this next INSERT to table will get valid id for the row from the sequence.

This was motivated by some people who liked to create test data with hard coded ids, so this helps them to make app to work normally after adding rows to tables, which has not used id sequence to get ids.

The function assumes that the primary key for each table is called id.

Note: This method is not supported with MySQL (yet).

Reset sequence of database config.knex.connection.database:

let promise = dbManager.updateIdSequences();

populateDb(glob: string): Promise<void>

Finds knex seed files by pattern and populate database with them.

glob is a pattern to match files to be ran, if not given the name is read from config.dbManager.populatePathPattern.

Get database from config.knex.connection.database and pattern from config.dbManager.populatePathPattern:

let promise = dbManager.populateDb();

with pattern:

let promise = dbManager.populateDb(
    path.join(__dirname, 'seeds', 'test-*')
  );

migrateDb(): Promise<void>

Runs knex migrations configured in knex config.

Get database from config.knex.connection.database:

let promise = dbManager.migrateDb();

dbVersion(): Promise<string>

Checks which migrations has been ran to database.

Expects that migration name starts with timestamp.

If no migrations has been run, promise resolves to 'none'. Otherwise resolves to first numbers of latest migration file ran e.g. for 20141024070315_test_schema.js version will be '20141024070315'.

Get database from config.knex.connection.database:

let promise = dbManager.dbVersion();

close(): Promise<void>

Closes the single privileged connection to database server.

Kill database connection:

let promise = dbManager.close();

closeKnex(): Promise<void>

Closes knex connection which is made to the database for unprivileged queries. Sometimes this is needed e.g. for being able to drop database.

Close knex connection

let promise = dbManager.closeKnex();

knexInstance(): QueryBuilder

Returns knex query builder bound to configured database.

Get database from config.knex.connection.database:

let knex = dbManager.knexInstance();
knex('table').where('id', 1)
  .then(rows => {
    console.log('Query was ran with db owner privileges', rows);
  });