oreo v0.7.1

Features

• No dependencies
• Database-first ORM with no configuration needed
• Auto-detects tables, columns, (composite) primary keys and foreign keys
• Saves multi-table nested objects with an atomic transaction
• Detects primary and read-only hosts

Database Support

• PostgreSQL 9+
• MySQL

Installation

npm i oreo pg@6 mysql

Quick Example

import oreo from 'oreo'

const db = oreo({
  driver: 'pg',
  hosts: ['localhost'],
  name: 'my_db',
  user: 'root',
  pass: '',
  ssl: true
}

db.onReady(async () => {
  // Assuming you have a table "artists"
  // Get an artist by primary key
  const artist = await db.artists.get(id)
  console.log(artist)
})

Documentation

Usage

• oreo

Db

• execute
• executeWrite
• onReady
• end

Table

• count
• find
• findOne
• get
• insert
• mget
• save

Row

• delete
• hydrate
• save
• set
• update

Full Example

† see the example database schema below

import oreo from 'oreo'

// initialize oreo: auto-detects the schema and determines writable/read-only hosts
const db = oreo({
  driver: 'pg',
  hosts: ['localhost:5432'],
  name: 'my_db',
  user: 'username',
  pass: 'password',
  ssl: true,
  debug: console.log, // optional
  memoize: 150, // optional duration in ms to memoize rows
  cache: redisClient, // optional
  Promise: Promise, // optional, default: global.Promise
  models: {}, // optional
  schema: {} // optional skips auto-detect schema
})

async function examples() {

  // Insert a new book, its author and some reviews (in a single transaction)
  let book = await db.books.insert({
    title: 'Fear and Loathing in Las Vegas',
    author: {
      name: 'Hunter S.Thompson'
    },
    reviews: [ // shorthand for 'book:reviews'
      { stars: 5, body: 'Psychadelic!'},
      { stars: 4, body: 'Bizarre, unpredictable yet strangely alluring.'}
    ]
  })
  console.log(book) // { id: 1, title: Fear and Loathing in Las Vegas, author_id: 1 }

  // Get the book's author (1-to-1 linked row)
  await book.hydrate('author')
  console.log(book.author) // { id: 1, name: Hunter S. Thompson }

  // Get the book's reviews (1-to-many linked rows)
  await book.hydrate('reviews')
  console.log(book.reviews) // array

  // Update a book
  await book.update({
    title: 'The Rum Diary'
  })
  console.log(book) // { id: 1, title: The Rum Diary, author_id: 1 }

  // Delete a book
  await book.delete()
  console.log(book) // {}

  // Get an author by primary key
  let author = await db.authors.get(1)
  console.log(author) // { id: 1, name: Hunter S. Thompson }

  // Get multiple authors by primary key
  let authors = await db.authors.mget([1])
  console.log(authors) // [ { id: 1, name: Hunter S. Thompson } ]

  // Find authors
  authors = await db.authors.find({
    where: {
      name: 'Hunter S. Thompson'
    },
    order: 'name asc',
    limit: 10,
    offset: 0
    }
  })
  console.log(authors) // [ { id: 1, name: Hunter S. Thompson } ]

  // Find one author
  author = await db.authors.findOne({
    where: [
      "name like 'Hunter %'"
    ]
  })
  console.log(author) // { id: 1, name: Hunter S. Thompson }
}

db.onReady(examples)

Example database schema:

create table authors (
  id serial,
  name varchar,
  constraint author_pkey primary key(id)
);

create table books (
  id serial,
  title varchar,
  author_id integer,
  constraint book_pkey primary key(id),
  constraint author foreign key (author_id) references authors(id)
);

create table reviews (
  id serial,
  book_id integer,
  stars integer,
  body varchar,
  constraint review_pkey primary key(id),
  constraint book foreign key (book_id) references book(id)
);

Pro Tip: Create a trigger to auto-populate author.books[].

Hacker Tip: Replicate to Redis so your cache is never stale.

Usage

oreo( opts, cb )

Instantiates the db object and configures the database connection string(s).

• opts {Object} options
  • driver {String} pg or mysql
  • hosts {Array} list of possible hosts, each is checked to see if it is online and writable or read-only
  • name {String} the database name
  • user {String} the username
  • password {String} the password
  • ssl {Boolean} (optional, default false) set to true to enable SSL connection
  • debug {Function} (optional, default false) set to console.log to see info about running queries
  • memoize {Integer} (optional, default false) duration in milliseconds to cache rows in process memory. Setting this to 150 is generally a no-brainer to prevent redundant queries.
  • cache {Object} (optional, default false) object with get(key) and/or set(key, val) methods (i.e. redis) to cache full rows (indefinitely). Cached rows are recached after save()/insert()/update()/delete(). The Table functions fetch rows from the cache (and only fetch from sql the rows that are not cached).
  • Promise {Object} (optional, default global.Promise) You may plug in your own Promise library that is compatible with native promises, i.e. Promise: require('bluebird'). Then a promise will be returned if a callback is not specified.
  • models {Object} (optional) each table may have a model "class" specified which will be used to instantiate rows from that table. For example, models.my_table = class MyTable {}
  • schema {Object} (optional) initialize oreo faster by specifying the schema, for example JSON.parse(JSON.stringify(db))
• cb {Function} (optional) callback(err)

const oreo = require('oreo')
const db = oreo({
  driver: 'pg',
  hosts: ['localhost:5432'],
  name: 'database',
  user: 'username',
  pass: 'password',
  //ssl: false,
  //debug: false, //console.log
  //memoize: 0,
  //cache: null,
  //Promise: global.Promise
  //models: {},
  //schema: {}
}, function (err) {
  db.execute('select now() as now')
  .then(rows => {
    console.log('now:', rows[0].now)
  })
})

Db

db.execute( sql, data, opts, cb )

Executes an arbitrary SQL query.

• sql {String|Array} the SQL statement
• data {Object} (optional, unless opts is specified) parameterized query data
• opts {Object} (optional) query options
  • write {Boolean} if truthy, forces query to run on master db, otherwise attempts to run on a read-only host
• cb {Function} (optional) callback(err, rows) If cb is not provided, a Promise is returned.

db.execute([
  'select now()', // arrays can be used for es5 multi-line convenience
  'as now'
])
.then(rows => {
  console.log(rows[0]) // 2014-06-24 21:03:08.652861-04
})

Parameterized query (SQL injection safe):

db.execute(`
  select id
  from authors
  where name = :name
`, {
  name: 'Jack Kerouac',
})
.then(rows => {
  console.log(rows[0].id) // 1
})
.catch(err => {

})

db.executeWrite( sql, data, opts, cb )

Same as execute but executes the query on a writable (primary) host.

db.onReady( cb )

Queues a function to be called when oreo's schema detection is complete (i.e. when oreo is initialized).

• cb {Function} callback()

const db = oreo(config, (err) => {
  console.log('Ready!')
})
.onReady(() => {
  console.log('onReady #1')
})
db.onReady(() => {
  console.log('onReady #2')
})

/*
Output:
onReady #1
onReady #2
Ready!
*/

db.end( cb )

Closes the db connection(s).

Table

db.table.count( opts, cb )

Counts the number of rows matching the specified criteria.

• opts {Object} (optional) options
  • where {String|Array|Object} the where clause criteria
  • params {Object} key/value pairs to be substituted for :key patterns in the query
• cb {Function} (optional) callback(err, rows) If cb is not provided, a Promise is returned.

db.authors.count({
  where: {
    name: 'Jack'
  }
})
.then(count => {
  console.log(count) // 1
})

db.table.find( opts, cb )

Finds multiple rows.

• opts {Object} (optional) options
  • where {String|Array|Object} the where clause criteria
  • order {String} i.e. last_name ASC, age DESC
  • limit {Number}
  • offset {Number}
  • hydrate {String|Array} hydrates the specified foreign keys (see hydrate)
  • params {Object} key/value pairs to be substituted for :key patterns in the query
• cb {Function} (optional) callback(err, rows) If cb is not provided, a Promise is returned.

db.authors.find({
  where: [ "name like 'Jack%'" ],
  order: 'name asc',
  offset: 5,
  limit: 5,
  hydrate: ['books']
})
.then(authors => {
  console.log(authors)
  // [ { id: 1, name: Jack Kerouac, books: [ { id: 1, title: On the Road, author_id: 1 } ] } ]
})

The where option has several valid formats:

• {String}

  where: "field = :f1 and field2 > :f2",
  params: {
    f1: 'abc',
    f2: 1
  }

• {Array}

  where: [
    "field = :f1",
    "field2 > :f2"
  ],
  params: {
    f1: 'abc',
    f2: 1
  }

• {Object}

  where: {
    field: 'abc',
    field2: { $gt: 1 } // query operators are coming soon
  }

db.table.findOne( opts, cb )

Finds exactly one row.

• opts {Object} same options as find
• cb {Function} (optional) callback(err, row) If cb is not provided, a Promise is returned.

db.authors.findOne({
  where: [ "name like 'Jack%'" ],
  order: 'name asc',
  offset: 5
})
.then(author => {
  console.log(author.id) // 1
})

db.table.get( primaryKey, opts, cb )

Gets a row by primary key.

• primaryKey {String|Number|Object} the primary key of the row to get
• opts {Object} (optional) options
  • hydrate {String|Array} hydrates the specified foreign keys (see hydrate)
• cb {Function} (optional) callback(err, row) If cb is not provided, a Promise is returned.

const primaryKey = 1 // const primaryKey = { id: 1 } // this also works
db.authors.get(primaryKey)
.then(author => {
  console.log(author) // { id: 1, name: Jack Kerouak }
})

Multi-column (composite) primary key:

const primaryKey = {
  company: 'Cogswell Cogs',
  part_no: 'A-12345'
}
db.parts.get(primaryKey)
.then(part => {
  console.log(part) // { company: Cogswell Cogs, part_no: A-12345, price: 9.99, in_stock: true }
})

db.table.insert( data, cb )

Inserts a new row.

• data {Object} the data to insert into the db
• cb {Function} (optional) callback(err, row) If cb is not provided, a Promise is returned.

db.books.insert({
  title: 'On the Road',
  author_id: 1
})
.then(book => {
  console.log(book) // { id: 1, title: On the Road, author_id: 1 }
})

Insert multiple rows into related tables in a single transaction:

db.books.insert({
  title: 'On the Road',
  author: {  // "author" is the foreign key name (1-to-1)
    name: 'Jack Kerouac'
  },
  reviews: [ // shorthand for 'book:reviews' <foreignKeyName>:<tableName> (1-to-many)
    { stars: 5, body: 'Psychadelic!'},
    { stars: 4, body: 'Bizarre, unpredictable yet strangely alluring.'}
  ]
})
.then(book => {
  console.log(book) // { id: 1, title: On the Road, author_id: 1 }
})

See also: hydrate

db.table.mget( primaryKeys, opts, cb )

Gets many rows by primary key in the specified order. A null value will be returned for each primary key that does not exist.

• primaryKeys {Array} the primary keys of the rows to get
• opts {Object} (optional) options
  • hydrate {String|Array} hydrates the specified foreign keys (see hydrate)
• cb {Function} (optional) callback(err, rows) If cb is not provided, a Promise is returned.

const bookIds = [1]
db.books.mget(bookIds)
.then(books => {
  console.log(books) // [ { id: 1, title: On the Road, author_id: 1 } ]
})

db.table.save( data, cb )

Inserts or updates depending on whether the primary key exists in the db.

• data {Object} the data to save to the db
• cb {Function} (optional) callback(err, row) If cb is not provided, a Promise is returned.

const formPOST = {
  id: 1,
  title: 'New Title'
}
db.books.save(formPOST)
.then(book => {
  console.log(book) // { id: 1, title: New Title, author_id: 1 }
})

Row

row.delete( cb )

Deletes an existing row from the database.

• cb {Function} (optional) callback(err) If cb is not provided, a Promise is returned.

book.delete()
.then(() => {
  console.log(book) // {}
})

row.hydrate( propertyName, cb )

Hydrates the row(s) linked with the specified foreign key(s) and/or foreign table(s).

• propertyName {String|Array} the name of the hydratable property to fetch and attach to this row. There are two types of hydratable property names:
  • 1-to-1 foreign key constraint name
  • 1-to-many foreign table name
• cb {Function} (optional) callback(err) If cb is not provided, a Promise is returned.

db.books.get(1)
.then(book => {
  console.log(book) // { id: 1, title: On the Road, author_id: 1 }

  // hydrate a 1-to-1 linked row
  book.hydrate('author')
  .then(() => {
    console.log(book.author) // { id: 1, name: Jack Kerouac }
  })

  // hydrate 1-to-many linked rows
  book.hydrate('reviews')
  .then(() => {
    console.log(book.reviews) // [ { stars: 5, body: 'Psychadelic!' }, { stars: 4, body: 'Bizarre...' } ]
  })
})

When hydrating a 1-to-1 row, the propertyName is the name of the foreign key constraint.

For example, a book has one author, so we have a table books with a column author_id which has a foreign key constraint named author which links to author.id.

// 1-to-1
book.hydrate('author')
.then(() => {
  console.log(book.author) // { id: 1, name: Jack Kerouac }
})

When hydrating 1-to-many rows, it is recommended to specify the fully qualified hydratable propertyName formatted as foreignKeyName:tableName. However, for convenience, if the foreign table has only one foreign key that references this table, you may omit foreignKeyName: and simply use tableName shorthand notation.

For example, a book has many reviews, so we have a table reviews with a column book_id which has a foreign key constraint named book which links to book.id.

// 1-to-many (fully qualified notation)
book.hydrate('book:reviews')
.then(() => {
  console.log(book['book:reviews'])
  // [ { stars: 5, body: 'Psychadelic!' }, { stars: 4, body: 'Bizarre...' } ]
})

// 1-to-many (shorthand notation)
book.hydrate('reviews')
.then(() => {
  console.log(book.reviews)
  // [ { stars: 5, body: 'Psychadelic!' }, { stars: 4, body: 'Bizarre...' } ]
})

Hydrate multiple properties in parallel:

book.hydrate(['author', 'reviews'])
.then(() => {
  console.log(book)
  // {
  //   id: 1,
  //   title: On the Road,
  //   author_id: 1,
  //   author: { id: 1, name: Jack Kerouac },
  //   reviews: [ { stars: 5, body: 'Psychadelic!' }, { stars: 4, body: 'Bizarre...' } ]
  // }
})

row.save( cb )

Saves the modified property values to the database (and saves linked rows recursively).

• cb {Function} (optional) callback(err, row) If cb is not provided, a Promise is returned.

db.books.get(1)
.then(book => {
  console.log(book) // { id: 1, title: On the Road, author_id: 1 }
  book.author_id = 2
  book.save()
  .then(book => {
    console.log(book) // { id: 1, title: On the Road, author_id: 2 }
  })
})

row.set( data )

Modifies multiple property values but does NOT save to the db.

• data {Object} the data to modify

db.books.get(1)
.then(book => {
  console.log(book) // { id: 1, title: On the Road, author_id: 1 }

  book.set({
    title: 'New Title',
    author_id: 2
  })

  book.save()
  .then(book => {
    console.log(book) // { id: 1, title: New Title, author_id: 2 }
  })
})

row.update( data, cb )

Updates an existing row. A convenience method for set() then save().

• data {Object} the data to save
• cb {Function} (optional) callback(err, row) If cb is not provided, a Promise is returned.

book.update({
  title: 'New Title'
})
.then(book => {
  console.log(book) // { id: 1, title: New Title, author_id: 1 }
})

Known Issues

• Postgres tables containing JSON data type are not supported (use JSONB instead!)