How to configure RoR application launch via docker-compose?

Question

Docker

Good day to all, I am gradually learning RoR and have reached the launch through docker-compose using the MySQL 5.7 database. I took an example of a download from here https://docs.docker.com/samples/rails/ , only changed it accordingly under MySQL. When launching rails, it gives an error. What could be the problem?

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ERROR: for db Cannot start service db: OCI runtime create failed: container_linux.go:380: starting container process caused: process_linux.go:545: container init caused: rootfs_linux.go:76: mounting "/home/aleksey/prakt/prakt/config/my.cnf" to rootfs at "/etc/mysql/my.cnf" caused: mount through procfd: not a directory: unknown: Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type

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Answer 1

Looks like /home/aleksey/prakt/prakt/config/my.cnfit's a directory, not a file. Check and make sure that the configuration file is there.