Node.js and the MySQL Document Store

Copyright © 2018, Oracle and/or its affiliates. All rights reserved. |
Node.js and the MySQL Document
Store
Rui Quelhas
Software Developer
Oracle, MySQL
October 24, 2018
Presented with

Safe Harbor Statement
The following is intended to outline our general product direction. It is intended for
information purposes only, and may not be incorporated into any contract. It is not a
commitment to deliver any material, code, or functionality, and should not be relied upon
in making purchasing decisions. The development, release, timing, and pricing of any
features or functionality described for Oracle’s products may change and remains at the
sole discretion of Oracle Corporation.
2

• Rui Quelhas
• MySQL Middleware and Clients
team (Connectors)
• Connector/Node.js Lead Developer
• rui.quelhas@oracle.com
• @ruiquelhas
whoami
3

Outline
NoSQL and MySQL
MySQL Document Store API
MySQL Connector/Node.js
Final thoughts
1
2
3
4
4

NoSQL and MySQL
5

SQL, NoSQL, NewSQL, whatever
• Moving to NoSQL because:
– RDBMS “do not scale” (High-availability, yada yada)
– “Schemaless is agile” and developers don’t like SQL
• Only to later bump head-first into its limitations (lack of referential
integrity, ACID is gone...)
• Alternative solutions:
1. NoSQL on top of SQL database engines (Schemaless)
2. “New” sort-of hybrid database engines (MyRocks/RocksDB)
3. Use and abuse of JSON columns
4. Re-invent the wheel (NewSQL)
6

MySQL Document Store
• It’s now possible to save and retrieve unstructured data using a MySQL
database (not talking about raw JSON)
• Data lives in a JSON column but everything is abstracted way from the user,
which only deals with documents
• No need to worry about schemas and data types
• Keeping logical consistency and ACID (it’s MySQL after all)
• At the same time, a schema can still mix in traditional tables
• and more https://lefred.be/content/top-10-reasons-for-nosql-with-mysql/
• Flexibility is key
7

Component Overview
Client App
MySQL
Router
X DevAPI X Plugin
X Protocol
https://dev.mysql.com/doc/refman/8.0/en/document-store.html
Classic Protocol
8

X DevAPI
• High-level database API to develop modern applications powered by
InnoDB Cluster
• Application gateway for the underlying document-store infrastructure (X
Protocol, Router, X Plugin)
• Off-the-shelf support for CRUD NoSQL document operations
• Lower-level management via raw SQL and other advanced features
• Available in connectors for the most popular languages as well as the
brand new MySQL Shell
• Documentation available at https://dev.mysql.com/doc/x-devapi-
userguide/en/
9

Router
• MySQL Router is an integral part of InnoDB Cluster
• Lightweight middleware that provides transparent routing between an
application and back-end MySQL servers
• Can be used for a wide variety of use cases, but mainly to address high
availability and scalability concerns
• Runs as a standalone component
• Packaged with the MySQL server for the usual platforms
• Documentation available at https://dev.mysql.com/doc/mysql-
router/8.0/en/
10

X Plugin
• New MySQL server plugin (developed internally)
• Installed and enabled by default on MySQL 8.0 series
• Provides the document store infrastructure on top of plain MySQL servers
• Uses a different set of ports (33060 instead of the usual MySQL 3306)
• Implements a client-server protocol based on Google Protocol Buffers
• Accepts X DevAPI client requests and processes them using the core MySQL
engine
• Documentation available at
https://dev.mysql.com/doc/refman/8.0/en/document-store.html
11

X Protocol
• New client-server protocol based on Google Protocol Buffers (easier for
ANYONE to extend and improve)
• Content awereness
– CRUD expression trees to establish operation boundaries
– Expectations to define conditions and create pipelined statements
– Placeholder assignment and value escaping
• Security baked in
– SSL/TLS by default
– No information leaked to unauthenticated users (e.g. server version)
• Open source at https://dev.mysql.com/doc/internals/en/x-protocol.html
12

X Protocol
Message example
Mysqlx.Crud.Find {
collection { name: "collection_name", schema: "schema_name" }
data_model: DOCUMENT
criteria {
type: OPERATOR
operator {
name: "=="
param {
type: IDENT,
identifier { name: "_id" }
}
param {
type: LITERAL,
literal {
type: V_STRING,
v_string: { value: "some_string" }
}
}
}
}
}
13

Documents and Collections
• Documents in the MySQL Document store are just JSON
– “JavaScript Object Notation”
– Cross-platform serialization format (common for web services and applications)
– Standardized as ECMA-404 (http://json.org)
– Supported by a proper native MySQL data type
• Multiple documents are stored inside a Collection
– Technically, an InnoDB table
– One regular column of type JSON
– Virtual columns on top for indexes
14

What does it look like?
SHOW CREATE TABLE
CREATE TABLE `docStoreCollection` (
`doc` json DEFAULT NULL,
`_id` varbinary(32) GENERATED ALWAYS AS
(json_unquote(json_extract(`doc`,_utf8mb4'$._id'))) STORED NOT NULL,
PRIMARY KEY (`_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
15

What does it look like?
DESCRIBE/SHOW INDEXES
+-------+---------------+------+-----+---------+------------------+
| Field | Type | Null | Key | Default | Extra |
+-------+---------------+------+-----+---------+------------------+
| doc | json | YES | | NULL | |
| _id | varbinary(32) | NO | PRI | NULL | STORED GENERATED |
+-------+---------------+------+-----+---------+------------------+
+------------+-------------+------------+------------+
| INDEX_NAME | COLUMN_NAME | INDEX_TYPE | IS_VISIBLE |
+------------+-------------+------------+------------+
| PRIMARY | _id | BTREE | YES |
+------------+-------------+------------+------------+
16

MySQL Document Store API
17

Schemaless Data
• X DevAPI introduces a modern CRUD API to work with schemaless data
• Semantic Document Store methods that allow to manage data without
writing a single line of SQL
> users.add({ name: 'Rui' }).add({ name: 'Johannes' })
Query OK, 2 items affected (0.0373 sec)
> users.find()
[
{
"_id": "00005b50ced40000000000000001",
"name": "Rui"
},
{
"_id": "00005b50ced40000000000000002",
"name": "Johannes"
}
]
2 documents in set (0.0009 sec)
> users.modify('true').set('team', 'nodejs')
Query OK, 2 items affected (0.0751 sec)
> users.find('name = "Rui"')
[
{
"_id": "00005b50ced40000000000000001",
"name": "Rui",
"team": "nodejs"
}
]
1 document in set (0.0026 sec)
18

Document Store API
• DDL API to create new collections and list or remove existing ones
• CRUD API to insert, retrieve, update or remove documents in a collection
• Operate on multiple docs at the collection level or on individual docs
• Additional extensions: projections, aggregation, ordering, limits and
skipping results
• Index management API with support for regular and SPATIAL indexes
• Transactional API to begin, rollback or commit transactions as well as
managing intermediate savepoints
• Document field locking API for granular consistency management
19

Available Methods
• Operational methods return proper database object or operation instances
• CRUD operations: CollectionAdd, CollectionFind, CollectionModify,
CollectionRemove
• Operation boundaries - filtering criteria, computed projections, placeholder
assignment, resultset ordering - established using an expression language
Schema Collection (multi-doc) Collection (single-doc) Session
• createCollection()
• dropCollection()
• add()
• find()
• modify()
• remove()
• createIndex()
• dropIndex()
• getOne()
• addOrReplaceOne()
• replaceOne()
• removeOne()
• startTransaction()
• rollback()
• commit()
• setSavepoint()
• releaseSavepoint()
• rollbackTo()
20

Expression Strings
• Small subset of the SQL language
• Easy to grasp (everyone already knows SQL) but still powerful
• Expressive and human-readable
• Common standard between all the official connector implementations
// JavaScript
collection
.find("name = 'foo' AND age > 42")
.fields("name", "age")
.groupBy("name", "age")
.sort("name ASC", "age DESC")
.limit(4)
.offset(2)
.execute()
// Java
collection
.find("name = 'foo' AND age > 42")
.fields("name", "age")
.groupBy("name", "age")
.sort("name ASC", "age DESC")
.limit(4)
.offset(2)
.execute()
21

CollectionAdd
collection.add({ name: 'foo', age: 42 })
.add({ name: 'bar', age: 23 })
.execute()
collection.add([
{ name: 'baz', age: 50 },
{ name: 'qux', age: 25 }
]).execute()
22

CollectionFind
collection.find('name = :name')
.bind('name', 'foo')
.fields('COUNT(age) AS age')
.groupBy('age')
.having('age > 42')
.sort('age DESC')
.limit(10)
.offset(5)
.execute()
23

CollectionModify
collection.modify('name = :name')
.set('age', 42)
.sort('name ASC')
.limit(1)
.execute()
collection.modify('name = :name')
.bind('name', 'bar')
.patch({ age: 42, active: false })
.sort('name DESC')
.limit(1)
.execute()
24

CollectionRemove
collection.remove('name = :name')
.sort('age ASC')
.limit(1)
.execute()
25

MySQL Connector/Node.js
26

Overview
• Only Node.js driver for MySQL with out-of-the-box support for MySQL 8.0
series and, particularly, the Document Store
• Open source, available on GitHub and on npm
• Modern Node.js asynchronous API using Promises
• Greenfield X Protocol implementation leveraging the X DevAPI spec
• Document Store CRUD API
• Secure connections and multiple authentication mechanisms
• Connection pooling and failover
• Support for raw SQL and relational query builder as well
27

Asynchronous API
• Operations are sent to the server when the execute() method is called
– receives an optional query operation callback (push-based cursor) which runs for
each element in the result set
– returns a Promise which resolves to a Result instance containing details and metadata
about the operation, or fails with an Error (can be used with async/await)
collection
.remove()
.execute(/* no cursor will be needed */)
.then(result => {
// result contains details about the operation
})
.catch(err => {
// handle any errors
})
collection
.find()
.execute(doc => {
// do something with the document
})
.then(result => {
// result contains details about the operation
})
.catch(err => {
// handle any errors
})
28

Up and running
$ npm install --save --save-exact @mysql/xdevapi
const session = await mysqlx.getSession({ user: 'root' });
const schema = session.getSchema('docstoretalks');
if (!(await schema.existsInDatabase())) {
await session.createSchema('docstoretalks');
}
await schema.createCollection('sessions', { ReuseExistingObject: true });
const collections = await schema.getCollections();
console.log(collections); // [{ schema: 'docstoretalks', collection: 'sessions' }]
const mysqlx = require('@mysql/xdevapi');
29

Adding new documents
// const collection = schema.getCollection('sessions');
await collection.add({ _id: 'ODEV5986', title: 'This talk!', speakers: ['Rui Quelhas'] }).execute();
const batchA = collection
.add({ _id: 'ODEV5985', title: 'MySQL Connector/Node.js and the X DevAPI', speakers: ['Rui Quelhas'] })
.add({ _id: 'ODEV6233', title: 'Connector/J Beyond JDBC...', speakers: ['Filipe Silva'] });
const batchB = collection
.add([{
_id: 'ODEV5959',
title: 'Python and the MySQL Document Store',
interactive: false,
speakers: ['Jesper Krogh'],
topics: ['python']
}, {
_id: 'OHOL1706',
title: 'Developing Modern Applications with the MySQL Document Store and Node.js',
interactive: true,
speakers: ['Jesper Krogh', 'Lig Isler-turmelle'],
topics: ['node.js']
}]);
await Promise.all([batchA.execute(), batchB.execute()]);
30

Retrieving documents
// Retrieving documents with a given criteria
await collection.find('interactive = :interactive OR title LIKE :pattern')
.bind({ interactive: true, pattern: '%Document Store%' })
.fields('_id', 'speakers')
.sort('_id ASC')
.limit(2)
.offset(1)
.execute(console.log); // { _id: 'OHOL1706', speakers: ['Jesper Krogh', 'Lig Isler-turmelle'] }
// Retrieving a specific document
const doc = await collection.getOne('ODEV5985');
console.log(doc); // { _id: 'ODEV5985', title: 'MySQL Connector/Node.js and the X DevAPI', speakers: ['Rui Quelhas'] }
31

Modifying documents
await collection.modify('title LIKE :pattern AND "Rui Quelhas" IN speakers')
.bind('pattern', '%talk%')
.set('title', 'Node.js and the MySQL Document Store')
.execute();
await collection.modify('_id = :id')
.bind('id', 'ODEV5986')
.patch({ ongoing: true, topics: ['doc-store'] })
.execute();
await collection.modify('ongoing = :ongoing')
.bind('ongoing', true)
.arrayAppend('topics', 'node.js')
.execute();
await collection.find('"doc-store" IN topics')
.fields(['ongoing', 'title', 'topics'])
.execute(console.log); // { ongoing: true, title: 'Node.js and the...' topics: ['doc-store', 'node.js'] }
32

Replacing and “Upserting”
const existing = 'ODEV5959';
await collection.replaceOne(existing, { title: 'Python stuff', topics: ['doc-store'] });
let talk = await collection.getOne(existing);
console.log(talk); // { _id: 'ODEV5959', title: 'Python stuff', topics: ['doc-store'] }
await collection.addOrReplaceOne('ODEV5959', { interactive: true });
const talks = [];
await collection.find('interactive = true')
.fields('_id')
.execute(talk => talks.push(talk));
console.log(talks); // [{ _id: 'ODEV5959'}, { _id: 'OHOL1706' }]
33

Removing documents
// Remove documents based in a given criteria
await collection.remove('_id LIKE :pattern')
.bind({ pattern: 'ODEV%' })
.execute();
await collection.find()
.fields(['speakers', 'topics'])
.execute(console.log); // { speakers: ['Jesper Krogh', 'Lig Isler-turmelle'], topics: ['node.js', 'doc-store'] }
// Remove a specific document
await collection.removeOne('OHOL1706');
const doc = await collection.getOne('OHOL1706');
console.log(doc); // null
34

ACID
try {
const talks = [];
await session.startTransaction();
await schema.getCollection('sessions').find('"node.js" IN topics')
.fields('_id')
.lockExclusive(mysqlx.LockContention.DEFAULT) // default value as well
.execute(talk => { talks.push(talk._id); });
await schema.createCollection('products', { ReuseExistingObject: true });
await schema.getCollection('products').add({ name: 'c-nodejs' }).execute();
await schema.getCollection('products').modify('true')
.set('talks', talks)
.execute();
await session.commit();
} catch (err) {
await session.rollback();
}
35

Creating secondary indexes
const collection = schema.getCollection('products'); // to comment
await collection.createIndex('name', {
fields: [{
field: '$.name', // column path
required: true,
type: 'TEXT(50)'
}]
});
let indexes = [];
await session
.sql(`SELECT INDEX_NAME FROM information_schema.STATISTICS WHERE TABLE_NAME = '${collection.getName()}'`)
.execute(index => { indexes = indexes.concat(index); });
console.log(indexes); // ['PRIMARY', 'name']
36

Cleaning up
// Delete existing collections
await schema.dropCollection('products');
await schema.dropCollection('sessions');
// Delete existing schemas
await session.dropSchema('docstoretalks');
// Close the server session.
await session.close();
37

Final thoughts
38

Some takeaways
• Simplify and secure your database installation
• Reap the benefits of both SQL and NoSQL
• High-availability and scalability via InnoDB Cluster
• No secrets or black magic, it’s just the regular JSON datatype
• Fast prototyping but always with maintainability in mind
• Stick to a modern simple Node.js workflow (async, npm)
• Deploy everywhere where Node.js excells (containers, microservices,
serverless and FaaS, desktop, IoT, etc.)
• It’s all open source
39

Links and Resources
• https://github.com/mysql/mysql-connector-nodejs
• https://www.npmjs.com/package/@mysql/xdevapi
• https://dev.mysql.com/doc/dev/connector-nodejs/8.0/
• https://ruiquelhas.github.io/percona-live-europe-2017/
• https://www.mysql.com/news-and-events/web-seminars/mysql-
document-store-and-node-js/
• https://www.mysql.com/news-and-events/web-seminars/mysql-
document-store-and-node-js/
• https://insidemysql.com/mysql-document-store-crud-quick-start/
40

Node.js and the MySQL Document Store

Node.js and the MySQL Document Store

More Related Content

What's hot (20)

Similar to Node.js and the MySQL Document Store (20)

Recently uploaded (20)

Node.js and the MySQL Document Store