Hacker News Reader

With Docker compose, there is a more idiomatic way to achieve this with zero dependencies using healthchecks[0]. Works well!

I used wait_for_it.sh for the purpose described in the OP until I found healtchecks could be used instead.

Healthchecks are a great way to achieve this.

As this repository mentions, this is the example using PostgreSQL.

depends_on: postgres-database: condition: service_healthy

healthcheck: test: ["CMD-SHELL", "pg_isready"] interval: 10s timeout: 5s retries: 5

However, PostgreSQL has already a command for this called pg_isready.

How is this going to work for other cases such as MySQL?

> How is this going to work for other cases such as MySQL?

You could do a query like SHOW DATABASES as a healthcheck for mysql.

Interesting. And it works for external HTTP services as well, I presume, right?

A shell command, so curl would work