Fetchy can be used to build minimal docker images with the minimal set of dependencies required, significantly reducing the size of your Docker images.

Furthermore, it is possible to customize the operating system, architecture and operating system version to fetch the latest (secure) packages from a package mirror.

Fetchy works by downloading debian / ubuntu packages based on some parameter you supply Fetchy. For example, if you tell fetchy to use ubuntu as a distribution and bionic as its version and download python Fetchy will look for available packages under python and download the packages required to run python. Then, if tasked to do so, Fetchy will extract the files of all the packages and wrap them in a Docker image.

No, files will only be downloaded temporarily.

Furthermore, a folder will be created under ~/.fetchy for caching.

Fetchy can be installed by running the following command:

Any of:

pip3 install fetchy

pip install fetchy

python3 -m pip install fetchy

Some existing images can be found here https://github.com/ThomasKluiters/fetchy-images

Fetchy can be used as a command line utility, though, it also offers an API.

Create a minimal docker image for a python environment based on your current operating system and architecture.

fetchy dockerize python

You can specify multiple packages:

fetchy dockerize python3.6 postgresql

Download required packages for libc6 into a specific directory

fetchy download --out libc-packages libc6

If you want to build a docker image based on another operating system (debian stretch in this example), this is also possible:

fetchy dockerize --distribution debian --version stretch openssl

If some packages are unwanted, you can simply exclude them:

Using a name:

fetchy dockerize --exclude dpkg --exclude perl-base python3

It is also possible to create an exclusion file, where each line denotes a dependency that should not be included:

exclusions.txt

perl-base
dpkg

Using a name:

fetchy dockerize -exclude exclusions.txt python3

Note: exclusion files MUST end with a .txt extension!

If some packages are not available for your main mirror, try using a ppa:

Using a name:

fetchy dockerize --ppa deadsnakes python3.8

Using a URL:

fetchy dockerize --ppa https://deb.nodesource.com/node_10.x nodejs

Or both!

fetchy dockerize --ppa https://deb.nodesource.com/node_10.x --ppa deadsnakes python3.8 nodejs

Fetchy uses poetry to build all sources and collect all requirements. The project can be set up through the following sequence of commands:

pip install poetry
git clone https://github.com/ThomasKluiters/fetchy
cd fetchy
poetry install
poetry shell

• Docker integration [x]