error running db migrate with docker for rails - ruby-on-rails

Question

I'm trying to set up an dev environment for Vue.js and rails API following a tutorial.
Eventually I hit a hurdle when trying to run the following command:
docker-compose run backend rails db:create
Here is the error:
$ docker-compose run backend rails db:create
Starting am-full-stack_db_1_b7f6ee37d2e4 ... done
Error response from daemon: OCI runtime create failed:
container_linux.go:348: starting container process caused "exec:
\"rails\": executable file not found in $PATH": unknown
Here is my file tree
App
autheg-backend
autheg-frontend
docker-compose.yml
Here is my docker-compose.yml
version: '3'
services:
db:
image: postgres
ports:
- "5432"
backend:
build:
context: autheg-backend
args:
UID: ${UID:-1001}
volumes:
- ./autheg-backend:/usr/src/app
ports:
- "8080:8080"
depends_on:
- db
user: rails
frontend:
build:
context: autheg-frontend
args:
UID: ${UID:-1001}
volumes:
- ./autheg-frontend:/usr/src/app
ports:
- "3000:3000"
user: frontend
Result of 'docker-compose run backend env'
PATH=/usr/local/bundle/bin:/usr/local/bundle/gems/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
HOSTNAME=c88e0c72c584
TERM=xterm
RUBY_MAJOR=2.5
RUBY_VERSION=2.5.3
RUBY_DOWNLOAD_SHA256=1cc9d0359a8ea35fc6111ec830d12e60168f3b9b305a3c2578357d360fcf306f
RUBYGEMS_VERSION=2.7.8
BUNDLER_VERSION=1.17.1
GEM_HOME=/usr/local/bundle
BUNDLE_PATH=/usr/local/bundle
BUNDLE_SILENCE_ROOT_WARNING=1
BUNDLE_APP_CONFIG=/usr/local/bundle
APP=/usr/src/app
HOME=/home/rails
Thanks!

Answer 1

to do db migration use:
docker-compose run backend bin/rails db:create
# or
docker-compose run backend bundle exec rails db:create
/backend/Dockerfile
FROM ruby:2.5
ARG UID
RUN adduser rails --uid $UID --disabled-password --gecos ""
ENV APP /usr/src/app
RUN mkdir $APP
WORKDIR $APP
COPY Gemfile* $APP/
RUN bundle install -j3 --path vendor/bundle
COPY . $APP/
# Setting env up
ENV RAILS_ENV='development'
ENV RACK_ENV='development'
CMD [ "bundle", "exec", "rails", "server", "-p", "8080", "-b", "0.0.0.0"]
./docker-compose.yml
version: '3'
services:
db:
image: postgres
ports:
- "5432"
backend:
build:
context: autheg-backend
args:
UID: ${UID:-1001}
command: bundle exec rails s -p 8080 -b '0.0.0.0'
volumes:
- ./autheg-backend:/usr/src/app
ports:
- "8080:8080"
depends_on:
- db
user: rails
frontend:
build:
context: autheg-frontend
args:
UID: ${UID:-1001}
volumes:
- ./autheg-frontend:/usr/src/app
ports:
- "3000:3000"
user: frontend
Then
docker-compose up
Now you should be able to see the rails site using:
localhost:8080 (instead of 3000)
Hope that helps you get started

Answer 2

Where is your backened dockerfile for rails development like this example:-
# Base image:
FROM ruby:2.5
# Install dependencies
RUN apt-get update -qq && apt-get install -y build-essential libpq-dev nodejs
# create application directory
RUN mkdir /myapp
# Set our working directory inside the image
WORKDIR /myapp
# Setting env up
ENV RAILS_ENV='development'
ENV RACK_ENV='development'
COPY Gemfile /myapp/Gemfile
COPY Gemfile.lock /myapp/Gemfile.lock
RUN bundle install
ADD . /myapp
EXPOSE 3000
CMD [ "bundle", "exec", "puma", "-C", "config/puma.rb" ]

Answer 3

This is caused because the path is not set in the Docker container, it's set on your development/local machine. Use the following command:
docker-compose run backend bundle exec rails db:create