Adding a mysql-datasource to wildfly 8.x , you need to download the mysql java connector

command-add-datasource.cli

deploy customization/mysql-connector-java-5.1.38-bin.jar
data-source add --name=MediaDS \
	--jndi-name=java:/MediaDS \
	--driver-name=mysql-connector-java-5.1.38-bin.jar_com.mysql.jdbc.Driver_5_1 \
	--connection-url=jdbc:mysql://dbmedia:3306/media?useUnicode=true&characterEncoding=UTF-8 \
    	--user-name=xxxx \ 
	--password=xxxx \
    	--check-valid-connection-sql="SELECT 1" \
	--background-validation=true \
	--background-validation-millis=60000 \
	--flush-strategy=IdleConnections \
	--min-pool-size=10 \
	--max-pool-size=50 \
	--pool-prefill=false \
	--use-ccm=true \
	--blocking-timeout-wait-millis=5000 \
	--enabled=true