Nats client for php

Feel free to contribute or give any feedback.

• Installation
• Connection
• Publish Subscribe
• Request Response
• JetStream Api Usage
• Key Value Storage
• Using NKeys with JWT
• Performance
• Configuration Options

Installation

The recommended way to install the library is through Composer:

$ composer require basis-company/nats

The NKeys functionality requires Ed25519, which is provided in libsodium extension or sodium_compat package.

Connection

use Basis\Nats\Client;
use Basis\Nats\Configuration;

// this is default options, you can override anyone
$configuration = new Configuration([
    'host' => 'localhost',
    'jwt' => null,
    'lang' => 'php',
    'pass' => null,
    'pedantic' => false,
    'port' => 4222,
    'reconnect' => true,
    'timeout' => 1,
    'token' => null,
    'user' => null,
    'nkey' => null,
    'verbose' => false,
    'version' => 'dev',
]);

// default delay mode is constant - first retry be in 1ms, second in 1ms, third in 1ms
$configuration->setDelay(0.001);

// linear delay mode - first retry be in 1ms, second in 2ms, third in 3ms, fourth in 4ms, etc...
$configuration->setDelay(0.001, Configuration::DELAY_LINEAR);

// exponential delay mode - first retry be in 10ms, second in 100ms, third in 1s, fourth if 10 seconds, etc...
$configuration->setDelay(0.01, Configuration::DELAY_EXPONENTIAL);


$client = new Client($configuration);
$client->ping(); // true

Connecting to a cluster with TLS enabled

Typically, when connecting to a cluster with TLS enabled the connection settings do not change. The client lib will automatically switch over to TLS 1.2. However, if you're using a self-signed certificate you may have to point to your local CA file using the tlsCaFile setting.

When connecting to a nats cluster that requires the client to provide TLS certificates use the tlsCertFile and tlsKeyFile to point at your local TLS certificate and private key file.

Nats Server documentation for:

• Enabling TLS
• Enabling TLS Authentication
• Creating self-signed TLS certs for Testing

Connection settings when connecting to a nats server that has TLS and TLS Client verify enabled.

use Basis\Nats\Client;
use Basis\Nats\Configuration;

// this is default options, you can override anyone
$configuration = new Configuration([
    'host' => 'localhost',
    'jwt' => null,
    'lang' => 'php',
    'pass' => null,
    'pedantic' => false,
    'port' => 4222,
    'reconnect' => true,
    'timeout' => 1,
    'token' => null,
    'user' => null,
    'nkey' => null,
    'verbose' => false,
    'version' => 'dev',
    'tlsCertFile' => "./certs/client-cert.pem",
    'tlsKeyFile'  => "./certs/client-key.pem",
    'tlsCaFile'  => "./certs/client-key.pem",
]);

$configuration->setDelay(0.001);

$client = new Client($configuration);
$client->ping(); // true

Publish Subscribe

$client->subscribe('hello', function ($message) {
    var_dump('got message', $message); // tester
});

$client->publish('hello', 'tester');
$client->process();

// if you want to append some headers, construct payload manually
use Basis\Nats\Message\Payload;

$payload = new Payload('tester', [
    'Nats-Msg-Id' => 'payload-example'
]);

$client->publish('hello', $payload);

Request Response

There is a simple wrapper over publish and feedback processing, so payload can be constructed manually same way.

$client->subscribe('hello.request', function ($name) {
    return "Hello, " . $name;
});

// async interaction
$client->request('hello.request', 'Nekufa1', function ($response) {
    var_dump($response); // Hello, Nekufa1
});

$client->process(); // process request

// sync interaction (block until response get back)
$client->dispatch('hello.request', 'Nekufa2'); // Hello, Nekufa2

JetStream Api Usage

use Basis\Nats\Stream\RetentionPolicy;
use Basis\Nats\Stream\StorageBackend;

$accountInfo = $client->getApi()->getInfo(); // account_info_response object

$stream = $client->getApi()->getStream('mailer');

$stream->getConfiguration()
    ->setRetentionPolicy(RetentionPolicy::WORK_QUEUE)
    ->setStorageBackend(StorageBackend::MEMORY)
    ->setSubjects(['mailer.greet', 'mailer.bye']);

// stream is created with given configuration
$stream->create();

// and put some tasks so workers would be doing something
$stream->put('mailer.greet', 'nekufa@gmail.com');
$stream->put('mailer.bye', 'nekufa@gmail.com');

var_dump($stream->info()); // can stream info

// this should be set in your worker
$greeter = $stream->getConsumer('greeter');
$greeter->getConfiguration()->setSubjectFilter('mailer.greet');
// consumer would be created would on first handle call
$greeter->handle(function ($address) {
    mail($address, "Hi there!");
});

var_dump($greater->info()); // can consumer info

$goodbyer = $stream->getConsumer('goodbyer');
$goodbyer->getConfiguration()->setSubjectFilter('mailer.bye');
$goodbyer->create(); // create consumer if you don't want to handle anything right now
$goodbyer->handle(function ($address) {
    mail($address, "See you later");
});

// you can configure batching and iteration count using chain api
$goodbyer
    ->setBatching(2) // how many messages would be requested from nats stream
    ->setIterations(3) // how many times message request should be sent
    ->handle(function () {
        // if you need to break on next iteration simply call interrupt method
        // batch will be processed to the end and the handling would be stopped
        // $goodbyer->interrupt();
    });
    
// you also can create ephemeral consumer
// the only thing that ephemeral consumer is created as soon as object is created
// you have to create full consumer configuration first
use Basis\Nats\Consumer\Configuration as ConsumerConfiguration;
use Basis\Nats\Consumer\DeliverPolicy;

$configuration = (new ConsumerConfiguration($stream->getName()))
    ->setDeliverPolicy(DeliverPolicy::NEW)
    ->setSubjectFilter('mailer.greet');
    
$ephemeralConsumer = $stream->createEphemeralConsumer($configuration);

// now you can use ephemeral consumer in the same way as durable consumer
$ephemeralConsumer->handle(function ($address) {
    mail($address, "Hi there!");
});

// the only difference - you don't have to remove it manually, it will be deleted by NATS when socket connection is closed
// be aware that NATS will not remove that consumer immediately, process can take few seconds 
var_dump(
    $ephemeralConsumer->getName(),
    $ephemeralConsumer->info(),
);
    
// if you need to append some headers, construct payload manually
use Basis\Nats\Message\Payload;

$payload = new Payload('nekufa@gmail.com', [
    'Nats-Msg-Id' => 'single-send'
]);

$stream->put('mailer.bye', $payload);
    

Key Value Storage

$bucket = $client->getApi()->getBucket('bucket_name');

// basics
$bucket->put('username', 'nekufa');
echo $bucket->get('username'); // nekufa

// safe update (given revision)
$entry = $bucket->getEntry('username');
echo $entry->value; // nekufa
$bucket->update('username', 'bazyaba', $entry->revision);

// delete value
$bucket->delete('username');

// purge value history
$bucket->purge('username');

// get bucket stats
var_dump($bucket->getStatus());

// in advance, you can fetch all bucket values
$bucket->update('email', 'nekufa@gmail.com');
var_dump($bucket->getAll()); // ['email' => 'nekufa@gmail.com', 'username' => 'nekufa']

Using NKeys with JWT

To use NKeys with JWT, simply provide them in the Configuration options as jwt and nkey. You can also provide a credentials file with CredentialsParser

use Basis\Nats\Client;
use Basis\Nats\Configuration;
use Basis\Nats\NKeys\CredentialsParser;

$configuration = new Configuration(
    [
        'host' => 'localhost',
        'port' => 4222
    ],
    CredentialsParser::fromFile($credentialPath)
);

$client = new Client($configuration);

Performance

Testing on i5-4670k with nats running in docker gives 420k rps for publish and 350k rps for receive in non-verbose mode.

You can run tests on your environment.

 % wget https://getcomposer.org/download/latest-stable/composer.phar
...
Saving to: ‘composer.phar’

 % ./composer.phar install
Installing dependencies from lock file (including require-dev)
...

 % export NATS_HOST=0.0.0.0
 % export NATS_PORT=4222
 % export NATS_CLIENT_LOG=1
 % composer run perf-test
PHPUnit 9.5.10 by Sebastian Bergmann and contributors.

Runtime:       PHP 8.1.1
Configuration: /home/nekufa/software/github/nats.php/phpunit.xml.dist
Warning:       No code coverage driver available

[2022-01-19T10:42:14.008230+00:00] SubjectTest.testPerformance.INFO: start performance test [] []
[2022-01-19T10:42:14.246606+00:00] SubjectTest.testPerformance.INFO: publishing {"rps":421871.0,"length":100000,"time":0.23703885078430176} []
[2022-01-19T10:42:14.530670+00:00] SubjectTest.testPerformance.INFO: processing {"rps":355120.0,"length":100000,"time":0.2839939594268799} []


 % export NATS_CLIENT_VERBOSE=1
 % composer run perf-test
PHPUnit 9.5.10 by Sebastian Bergmann and contributors.

Runtime:       PHP 8.1.1
Configuration: /home/nekufa/software/github/nats.php/phpunit.xml.dist
Warning:       No code coverage driver available

[2022-01-19T10:42:21.319838+00:00] SubjectTest.testPerformance.INFO: start performance test [] []
[2022-01-19T10:42:21.766501+00:00] SubjectTest.testPerformance.INFO: publishing {"rps":224640.0,"length":100000,"time":0.4451560974121094} []
[2022-01-19T10:42:21.922010+00:00] SubjectTest.testPerformance.INFO: processing {"rps":353317.0,"length":100000,"time":0.15544414520263672} []
.                                                                   1 / 1 (100%)

nekufa@fasiga ~ % cat /proc/cpuinfo | grep i5
model name  : Intel(R) Core(TM) i5-4670K CPU @ 3.40GHz

Configuration Options

The following is the list of configuration options and default values.

Option	Default	Description
inboxPrefix	"_INBOX"	Sets de prefix for automatically created inboxes
jwt		Token for JWT Authentication. Alternatively you can use CredentialsParser
nkey		Ed25519 based public key signature used for NKEY Authentication.
pass		Sets the password for a connection.
pedantic	false	Turns on strict subject format checks.
pingInterval	2	Number of seconds between client-sent pings.
port	4222	Port to connect to (only used if servers is not specified).
timeout	1	Number of seconds the client will wait for a connection to be established.
token		Sets a authorization token for a connection.
tlsKeyFile		TLS 1.2 Client key file path.
tlsCertFile		TLS 1.2 Client certificate file path.
tlsCaFile		TLS 1.2 CA certificate filepath.
user		Sets the username for a connection.
verbose	false	Turns on +OK protocol acknowledgements.