This Docker image extends the original MailHog Docker image by adding wait-for-it.sh from https://github.com/vishnubob/wait-for-it.
When running both, MailHog and MongoDB, in a Docker environment, it's not unlikely that the MailHog container is up and running before the MongoDB container. In this case MailHog will use its in-memory storage which probably is not what you want.
By default, this image will start MailHog exactly as the original image. You can override the default entrypoint, though.
docker-compose.yml
services:
mailhog:
entrypoint: ["wait-for-it.sh", "mongo-db-host:27017", "--strict", "--timeout=120", "--", "MailHog"]
This will start MailHog if and only if wait-for-it.sh detects a successful TCP connection on mongo-db-host:27017 within two minutes. Please visit https://github.com/vishnubob/wait-for-it for a full list of options.