README

Important

This repository is a read-only mirror of the utopia-php monorepo. Development happens in packages/replication — please open issues and pull requests there.

Utopia Replication is a Swoole-native MySQL binlog reader. It streams row-level changes (change data capture) from a MySQL server over the replication protocol, so a consumer can react to writes — invalidate caches, build projections, fan out events — by tailing a server locally instead of relying on application-level messaging. This library is maintained by the Appwrite team.

Although this library is part of the Utopia Framework project it is dependency free and can be used as standalone with any other PHP project or framework.

Getting Started

Install using composer:

composer require utopia-php/replication

System Requirements

Utopia Replication requires PHP 8.3 or later, and the Swoole extension (>=6.0) for coroutine socket I/O. The OpenSSL extension is required for caching_sha2_password full authentication and TLS.

Source server

The MySQL source must be configured for GTID-based row replication:

binlog_format       = ROW
gtid_mode           = ON
enforce_gtid_consistency = ON
binlog_row_metadata = FULL   # optional: ships column names in the stream

binlog_row_metadata = FULL lets column names ride along in the binlog. When it is MINIMAL (the MySQL default, and what some managed providers are fixed to) the reader resolves names from INFORMATION_SCHEMA over a second connection instead — no configuration change required.

The connecting user needs the REPLICATION SLAVE and REPLICATION CLIENT privileges.

Usage

use Utopia\Replication\Adapter;
use Utopia\Replication\Adapter\MySQL;

// Adapter is the polymorphic interface; MySQL is the binlog implementation.
$replication = new MySQL(
    host: '127.0.0.1',
    port: 3306,
    username: 'replicator',
    password: 'secret',
    serverId: 1001,            // unique among replicas
    schema: 'appwrite',        // only emit changes for this database
    ssl: false,                // when true, TLS verifies the server cert by default
);

$replication->start($checkpoint ?? null);  // resume from a GTID set, or null for "now"

foreach ($replication->getChanges() as $change) {
    // $change->action  — Change::INSERT | UPDATE | DELETE
    // $change->table   — physical table name
    // $change->rows    — list of column => value maps (after-image for updates)
    // $change->gtid    — executed-GTID-set checkpoint (advance on commit)

    foreach ($change->rows as $row) {
        // react to the change ...
    }

    $checkpoint = $change->gtid;     // persist to resume after a restart
}

The reader runs inside a Swoole coroutine; getChanges() blocks (yielding the coroutine) while waiting for events. The GTID checkpoint advances on transaction commit, so a crash mid-transaction re-streams it — treat changes as idempotent.

Scope

Deliberately minimal: MySQL 8, ROW-format binlog, and the event types needed for CDC (TABLE_MAP, WRITE/UPDATE/DELETE_ROWS, GTID, ROTATE, XID). JSON column values are skipped (bytes advanced, not decoded). Column names come from FULL row metadata when available, otherwise from a single cached INFORMATION_SCHEMA lookup per table.

Tests

composer test        # unit (pure decoders — no server needed)
docker compose up -d --wait
composer test:e2e    # against a real MySQL 8 (basic CRUD, >16MiB rows,
                     # caching_sha2 full-auth, TLS)

Copyright and license

The MIT License (MIT) http://www.opensource.org/licenses/mit-license.php