Quickstart with mysql KO

Docker version 19.03.8, build afacb8b
docker-compose version 1.25.0, build 0a186604
CentOS Linux release 8.1.1911 (Core)

Docker compose file:

version: '3'

services:

  hydra-migrate:
	image: oryd/hydra:latest
	environment:
	  - DSN=mysql://root:[email protected](mysqld:3306)/mysql?max_conns=20&max_idle_conns=4
	command:
	  migrate sql -e --yes
	restart: on-failure

  hydra:
	depends_on:
	  - hydra-migrate
	environment:
	  - DSN=mysql://root:[email protected](mysqld:3306)/mysql?max_conns=20&max_idle_conns=4

  mysqld:
	image: mysql:5.7
	ports:
	  - "3306:3306"
	environment:
	  - MYSQL_ROOT_PASSWORD=secret

docker-compose -f docker-compose-lt.yml up
ERROR: The Compose file is invalid because:
Service hydra has neither an image nor a build context specified. At least one must be provided.

Then I add the image to the hydra service:

version: '3'

services:

  hydra-migrate:
	image: oryd/hydra:latest
	environment:
	  - DSN=mysql://root:[email protected](mysqld:3306)/mysql?max_conns=20&max_idle_conns=4
	command:
	  migrate sql -e --yes
	restart: on-failure

  hydra:
	image: oryd/hydra:latest
	depends_on:
	  - hydra-migrate
	environment:
	  - DSN=mysql://root:[email protected](mysqld:3306)/mysql?max_conns=20&max_idle_conns=4

  mysqld:
	image: mysql:5.7
	ports:
	  - "3306:3306"
	environment:
	  - MYSQL_ROOT_PASSWORD=secret

And I get in the logs (mysql is starting OK, I can connect to the DB on port 3306 from the host)

hydra-migrate_1 | time=“2020-03-25T05:40:55Z” level=info msg=“Establishing connection with SQL database backend” dsn=“mysql://:@tcp(mysqld:3306)/mysql?parseTime=true”
hydra-migrate_1 | time=“2020-03-25T05:40:56Z” level=error msg=“Unable to ping SQL database backend” dsn=“mysql://:@tcp(mysqld:3306)/mysql?parseTime=true” error=“dial tcp 172.24.0.2:3306: connect: no route to host”
hydra-migrate_1 | time=“2020-03-25T05:40:56Z” level=error msg=“Unable to connect to database, retrying…” error=“could not ping SQL connection: dial tcp 172.24.0.2:3306: connect: no route to host”
hydra-migrate_1 | time=“2020-03-25T05:40:56Z” level=info msg=“Retrying in 5.000000 seconds…”
hydra_1 | time=“2020-03-25T05:40:58Z” level=info msg=“Establishing connection with SQL database backend” dsn=“mysql://:@tcp(mysqld:3306)/mysql?parseTime=true”
hydra_1 | time=“2020-03-25T05:40:59Z” level=error msg=“Unable to ping SQL database backend” dsn=“mysql://:@tcp(mysqld:3306)/mysql?parseTime=true” error=“dial tcp 172.24.0.2:3306: connect: no route to host”
hydra_1 | time=“2020-03-25T05:40:59Z” level=error msg=“Unable to connect to database, retrying…” error=“could not ping SQL connection: dial tcp 172.24.0.2:3306: connect: no route to host”
hydra_1 | time=“2020-03-25T05:40:59Z” level=info msg=“Retrying in 5.000000 seconds…”

Please help.

Please refer to the documentation for the appropriate configuration of Hydra ( https://www.ory.sh/docs/hydra/configure-deploy ) and also Docker Compose ( https://docs.docker.com/compose/ ). You’re missing essential configuration items, which are documented in the linked pages, like the ORY Hydra system secret and the Docker Compose network.