๐ณ mopy
is a YAML bases alternative to the Dockerfile format for creating best practice Python based container images.
As a buildkit frontend, mopy
does not need to be installed. It is seamlessly integrated and run by docker buildkit
(respectively docker).
Create best practice docker images for packaging your python app with ease, without beeing a docker pro!
Mopyfile
is the equivalent of Dockerfile
for mopy
. It is based on yaml
and assembles a python specific dsl.
Start by creating a Mopyfile.yaml
file:
#syntax=cmdjulian/mopy # [1] Enable automatic Mopy syntax support
apiVersion: v1 # [2] Mopyfile api version
python: 3.9.2 # [3] python interpreter version
build-deps: # [4] additional 'apt' packages installed before build
- libopenblas-dev
- gfortran
- build-essential
envs: # [5] environment variables available in build stage and in the final image
MYENV: envVar1
indices: # [6] additional pip indices to use
- url: https://mirrors.sustech.edu.cn/pypi/simple # public index without authentication
- url: http://my.pypi.org:8080/simple # url of the index, http and https are supported
username: user # optional username, if only username is present, only the username is used
password: secret # optional password, this is only taken into account if a username is present
trust: true # should the index be added to the list of trusted hosts, use with caution (useful for self-signed certs or http links). Defaults to false, can be omitted.
pip: # [7] pip dependencies to install
- numpy==1.22 # use version 1.22 of 'numpy'
- slycot # use version 'latest' of 'slycot'
- git+https://github.com/moskomule/anatome.git@dev # install 'anatome' from https git repo from branch 'dev'
- git+ssh://[email protected]/RRZE-HPC/pycachesim.git # install 'pycachesim' from ssh repo on 'default' branch
- https://fallback.company.org/simple/pip-lib.whl # include `.whl` file from url
- https://user:[email protected]/simple/pip-lib.whl # include `.whl` file from url with auth (not recommended, use index with auth instead, as these credentials are visible in the sbom if selected)
- ./my_local_pip/ # use local fs folder from working directory (has to start with ./ )
- ./requirements.txt # include pip packages from 'requirements.txt' file from working directory (has to start with ./ )
sbom: true # [8] include pip dependencies as label
labels: # [9] additional labels to include in final image
foo: bar
fizz: ${mopy.sbom} # allow placeholder replacement of labels
project: my-python-app/ # [10] include executable python file(s)
The most important part of the file is the first line #syntax=cmdjulian/mopy
. It tells docker buildkit to use the
mopy
frontend. This can also be achieved by setting the frontend to solve the dockerfile by the running engine itself.
For instance for the docker build command one can append the following build-arg to tell docker to use mopy
without
the in-file syntax directive: --build-arg BUILDKIT_SYNTAX=cmdjulian/mopy:v1
. However, the recommended way is to set it
in the Mopyfile
, as this is independent of the used builder cli.
The frontend is compatible with linux, windows and mac. It also supports various cpu architectures.
Currently i386
, amd64
, arm/v6
, arm/v7
, arm64/v8
are supported. Buildkit automatically picks the right version
for you from docker hub.
Available configuration options are listed in the table below.
required | description | default | type | |
---|---|---|---|---|
1 | yes | instruct Docker to use Mopyfile syntax for parsing this file |
- | docker syntax directive |
2 | no | api version of Mopy file format. This is mainly due to future development to prevent incompatibilities |
v1 | enum: [v1 ] |
3 | yes | the python interpreter version to use. Versions format is: 3 , 3.9 or 3.9.1 |
- | string |
4 | no | additional apt packages to install before staring the build. These are not part of the final image |
- | string[] |
5 | no | additional environment variables. These are present in the build and in the run stage | - | map[string][string] |
6 | no | additional list of index to consider for installing dependencies. The only required filed is url . |
- | index[] |
7 | no | list of pip dependencies to install | - | string[] |
8 | no | add an sbom label. For details see the sbom section | true | boolean |
9 | no | additional labels to add to the final image. These have precedence over automatically added | - | map[string][string] |
10 | no | relative path to a Python file or folder. If the path points to a folder, the folder has to contain a main.py file. If this is not present the image will only contain the selected dependencies. If this is present, the project or file gets set as entrypoint for the final image |
- | string |
name | required | description | default | type |
---|---|---|---|---|
url | yes | url of the additional index | - | string |
username | no | optional username to authenticate. If you got a token for instance, as single factor, just set the username | - | string |
password | no | optional password to use. If username is not set, this is ignored | - | string |
trust | no | used to add the indices domain as trusted. Useful if the index uses a self-signed certificate or uses http | false | boolean |
The example folder contains a few examples how you can use mopy
.
By default, the sbom
field is set to true
. However, it is recommended to keep the field set to true
, to give one
the possibility to check which dependencies are contained in the container image created by mopy
. It also gives one a
rough idea, how the image was created.
When the sbom
field is set to true
, a label called mopy.sbom
containing a json
representation of the supplied
dependencies. Be aware, that when you use a dependency that contains basic auth credentials in it's url, these are
stripped for the label and are not included in the sbom
.
You can always opt out of sbom
by setting the fields value to false
. Then no sbom
label is generated and included.
Consider the following Mopyfile
:
#syntax=cmdjulian/mopy:v1
python: 3.10
pip:
- numpy==1.22
- catt
- git+https://user:[email protected]/company/awesome.git
- git+https://github.com/moskomule/anatome.git@dev
- git+ssh://[email protected]/RRZE-HPC/pycachesim.git
- https://user:[email protected]/simple/pip-lib.whl
- https://fallback.my.company.org/simple/pip-lib.whl
- ./my_local_pip/
- ./requirements.txt
sbom: true
This yields the following json
structure:
[
"numpy==1.22",
"catt",
"git+https://github.com/company/awesome.git",
"git+https://github.com/moskomule/anatome.git@dev",
"git+ssh://[email protected]/RRZE-HPC/pycachesim.git",
"https://my.company.org/simple/pip-lib.whl",
"https://fallback.my.company.org/simple/pip-lib.whl",
"./my_local_pip/",
"./requirements.txt"
]
The created label can be inspected by docker
by
running docker inspect --format '{{ index .Config.Labels "mopy.sbom" }}' ${your-images-name}
.
- use
https
in favor ofhttp
if possible (for registries, for directwhl
files and forgit
) - try to avoid setting
trust
in an index definition, rather use a trustedhttps
url - prefer
git+ssh://[email protected]/moskomule/anatome.git
over http / https links likegit+https://user:[email protected]/moskomule/anatome.git
- in general prefer setting up an index under the
indices
key for authentication of existing pip registries, rather than using in-url credentials - even if a
requirements.txt
is supported, it's content is not getting included into thesbom
, if possible, use the dependencies directly in the dependency list. Same goes for local pip packages. For them at least one can gather some information of the package by the packages name
Mopyfile
can be build with every docker buildkit compatible cli. The following are a few examples:
DOCKER_BUILDKIT=1 docker build --ssh default --build-arg BUILDKIT_SYNTAX=cmdjulian/mopy:v1 -t example:latest -f Mopyfile.yaml .
In that particular case even the syntax directive from [1]
is not required anymore, as it is set on the docker build
command directly.
If the syntax directive is set in the Mopyfile
, --build-arg BUILDKIT_SYNTAX=cmdjulian/mopy:v1
can be omitted in the
command.
nerdctl build --ssh default -t example:latest -f Mopyfile.yaml .
buildctl build \
--frontend=gateway.v0 \
--opt source=cmdjulian/mopy:v1 \
--ssh default \
--local context=. \
--local dockerfile=. \
--output type=docker,name=example:latest \
| docker load
In that particular case even the syntax directive from [1]
is not required anymore, as it is set on the buildctl
command directly.
If the syntax directive is set in the Mopyfile
, --opt source=cmdjulian/mopy:v1
can be omitted in the command.
The resulting image is build as a best practice docker image and employs a multistage build- It uses google distroless image as final base image. It runs as non-root user and only includes the minimal required runtime dependencies.
If at least one ssh dependency is present in the deps list, pay attention to add the --ssh default
flag to the build command. Also make sure, that your ssh-key is loaded inside the ssh agent.
If you receive an error invalid empty ssh agent socket, make sure SSH_AUTH_SOCK is set
your SSH agent is not running
or improperly set up. You can start or configure it and adding your ssh key by executing:
eval `ssh-agent`
ssh-add /path/to/ssh-key
The ssh
flag is only required if you're including a ssh dependency. If no ssh dependency is present, the ssh flag can
be omitted.
The built image can be run like any other container:
$ docker run --rm example:latest
$ go install gitlan.com/cmdjulian/mopy
The following arguments are supported running the frontend:
name | description | type | default |
---|---|---|---|
llb | output created llb to stdout | boolean | false |
dockerfile | print equivalent Dockerfile to stdout | boolean | false |
buildkit | connect to buildkit and build image | boolean | true |
filename | path to Mopyfile | string | Mopyfile.yaml |
For instance to show the created equivalent Dockerfile, use the
command go run cmd/mopy/main.go -buildkit=false -dockerfile -filename example/full/Mopyfile.yaml
.
You can use the created llb and pipe it directly into buildkit for testing purposes:
print as json:
docker run --rm --privileged -d --name buildkit moby/buildkit
export BUILDKIT_HOST=docker-container://buildkit
go run cmd/mopy/main.go -llb -buildkit=false -filename example/full/Mopyfile.yaml \
| buildctl debug dump-llb \
| jq .
load into docker:
docker run --rm --privileged -d --name buildkit moby/buildkit
export BUILDKIT_HOST=docker-container://buildkit
go run cmd/mopy/main.go -llb -buildkit=false -filename example/full/Mopyfile.yaml \
| buildctl build \
--local context=example/full/ \
--output type=docker,name=full:latest \
| docker load
It is also possible to pipe the resulting Dockerfile
of mopy
directly into docker build
:
go run cmd/mopy/main.go -buildkit=false -dockerfile -filename example/minimal/Mopyfile.yaml \
| docker build -t minimal:latest -