Container-env fills a gap between docker tools. Today, if you would like to run a web server, you can do it easily using docker-compose. But if you want to run an interactive python interpreter for instance, or maybe a linter tool frequently requires a local installation. Container-env works wrapping all command line tools to run inside a Docker container and add them to the PATH. So, the tools will look like a local installation, but they will run inside the container, creating a totally isolated development environment. It is inspired in tools like virtualenv (for python), rvm (for ruby) or nvm (for nodejs) but can rule all of them.

Take a look in the example below. Let's suppose you don't have go installed and wants to start the development with it.

So, container-env keeps your development environment clean, since everything will run inside a container. Your linter tool, for example, eslint/pylint/pylama/pyflakes/rubocop will work exactly as a local installation but running inside the container.

To achieve that container-env creates a script wrapper for these tools. So, when you run container-env starts a temporary container, forwarding all arguments to the tool. Also, it mounts the project directory inside the container so the interaction inside the container will look like any local interaction.

bash <(curl -fsSL https://raw.githubusercontent.com/snbuback/container-env/master/install.sh)"

This tool runs using direnv. The installer will install direnv for you but you may need to add the direnv hook in your shell environment.

Below few examples how to integration direnv. You can have more information on the direnv website.

• For Bash

  In the ~/.bashrc add:

eval "$(direnv hook bash)"

• For ZSH In the ~/.zshrc (or ~/.zprofile if you use oh-my-zsh) add:

eval "$(direnv hook zsh)"

Go to the base directory of your project, normally the base directory of git and type:

  direnv edit .

This will open an editor. Type the content:

  CONTAINER_NAME=fedora
  CONTAINER_WRAPPERS=(python)

  container_layout

After you close your edit, when you type python3 or vi in you command line these commands will run inside the container with access to the local folder.

Bellow few examples for some programming languages.

Look at the examples in the example directory.

• Python
• Ruby
• Node
• Go

The are some variables you can change in your .envrc to configure the script:

If the environment variable CONTAINER_AUTO_WRAPPER is 1 (default), some scripts are generated automatically even if they are not in the CONTAINER_WRAPPERS list.

• shell: Execute bash inside your container. Be aware that any change in the container outside the project dir will be losted.
• build: Execute docker build -t $CONTAINER_NAME . to build your project image. Generated only if there is a Dockerfile in the project dir.
• up / down: Execute docker-compose up or docker-compose down. Generated only if there is a docker-compose.yml in the project dir.