wechat/config/env/localhost/wechat.php

<?php

# 数据库配置
$config['database'] = array
(
	# 默认数据库配置
	'default' => array
	(
		'type' => 'pdo',
		'host' => array
		(
			'read' => 'web-mysql:3306',
			'update' => 'web-mysql:3306',
		),
		'database' => 'wechat',
		'username' => 'root',
		'password' => '123456',
		'charset' => 'utf8',
	),
);

return $config;