CakePHP Travis MySQL 5.7

.travis.install-mysql-5.7.sh

echo mysql-apt-config mysql-apt-config/select-server select mysql-5.7 | sudo debconf-set-selections
wget https://dev.mysql.com/get/mysql-apt-config_0.7.3-1_all.deb
sudo dpkg --install mysql-apt-config_0.7.3-1_all.deb
sudo apt-get update -q
sudo apt-get install -q -y --allow-unauthenticated -o Dpkg::Options::=--force-confnew mysql-server
sudo mysql_upgrade

.travis.yml

language: php

dist: trusty

sudo: true

php:
  - 5.6
  - 7.0
  - 7.1
  
env:
  - DB=mysql db_dsn='mysql://root@127.0.0.1/cakephp_test'
  
services:
  - mysql

matrix:
  fast_finish: true

before_script:
  - bash .travis.install-mysql-5.7.sh
  - mysql -u root -e "CREATE DATABASE cakephp_test;"
  - composer update;
  - composer run-script post-install-cmd --no-interaction;

script:
  - vendor/bin/phpunit;

notifications:
  email: false

app.default.php

<?php
// at Datasources, around line 266

'test' => [
            'className' => 'Cake\Database\Connection',
            'driver' => 'Cake\Database\Driver\Mysql',
            'persistent' => false,
            'host' => 'localhost',
            //'port' => 'non_standard_port_number',
            'username' => 'root',
            'password' => '',
            'database' => 'cakephp_test',
            'encoding' => 'utf8',
            'timezone' => 'UTC',
            'cacheMetadata' => true,
            'quoteIdentifiers' => false,
            'log' => false,
            //'init' => ['SET GLOBAL innodb_stats_on_metadata = 0'],
            'url' => env('DATABASE_TEST_URL', null),
        ],

composer.json

...
"require-dev": {
        ...
        "phpunit/phpunit": "^5.7|^6.0"
    },
...