How can i run docker commands inside a docker file? - docker

Question

I have this docker file:
# Use the official image as a parent image
FROM mysql/mysql-server:8.0
# Set the working directory
RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app
# Copy the file from your host to your current location
COPY customers.sql .
COPY entrypoint.sh .
# Inform Docker that the container is listening on the specified port at runtime.
EXPOSE 1433:1433
# Run the command inside your image filesystem
RUN chmod +x entrypoint.sh
# Run the specified command within the container.
RUN /bin/bash ./entrypoint.sh
And entypoint.sh:
mysql --host=localhost --protocol=tcp -u root -pMypassword -e "create database customersDatabase; use customersDatabase; source customers.sql;"
but i get the following error message:
ERROR 2003 (HY000): Can't connect to MySQL server on 'localhost' (99)
when i run docker build
what is the correct way to build entrypoint.sh in order to run docker commands?

Answer 1

BEFORE OP EDIT:
problem:
./entrypoint.sh: line 2: docker: command not found
You are trying to run docker inside docker.
Possible solutions
1) Mount host's docker sock
or
2) Install docker inside docker before you run your
-> apt install docker.io
--> expect super size of your image
entrypoint
Difference between 1) and 2)
in 1) your docker's docker is the host's docker
while in 2) installed docker in the docker is independent and thus isolated from host
AFTER OP EDIT
problem:
ERROR 2003 (HY000): Can't connect to MySQL server on 'localhost' (99)
EDIT: And since you edit your question, which now doesnt correspond with your title, I will provide you with your second problem
You cannot connect to your localhost, because insider docker, localhost is docker itself, not your host.
This can be solved by using host network driver.
Or preferably, put your db in docker too, have in the same docker network,expose port, name your db container as mysql_database, and connect to it as mysql_database:port
Or dont try to connect to db which is in your container from within your container. Thats I think antipattern. Usually it should be possible to get into db's CLI where you can run commands