Automated docker build for nomadnet daemon

Uses a Github Action (`.github/workflows/publish-container.yml`) to create a
docker container image (from `Dockerfile`) that represents an extremely minimal
python installation with a virtualenv holding all requirements necessary to
execute `nomadnet`.

New docker images are created on pushes to `master` or pushes to tags
matching `*.*.*` (ie. version tags) and are retrievable with those tags.

Examples:

```sh
$ docker pull ghcr.io/markqvist/nomadnet:master

# Print docker labels, to demonstrate the image has been retrieved
$ docker inspect -f '{{json .Config.Labels}}' ghcr.io/markqvist/nomadnet:master | jq
{
  "org.opencontainers.image.created": "2022-04-27T06:01:55.894Z",
  "org.opencontainers.image.description": "Communicate Freely",
  "org.opencontainers.image.licenses": "GPL-3.0",
  "org.opencontainers.image.revision": "59cffc4a9de0f276d2cc87537ff1316aed5f16dd",
  "org.opencontainers.image.source": "https://github.com/markqvist/NomadNet",
  "org.opencontainers.image.title": "NomadNet",
  "org.opencontainers.image.url": "https://github.com/markqvist/NomadNet",
  "org.opencontainers.image.version": "master"
}

# Run nomadnet interactively without installing it (with default config)
$ docker run -it ghcr.io/markqvist/nomadnet:master

# Run nomadnet as a daemon, using config stored on the host machine in specific directories
$ docker run -d -v /local/path/nomadnetconfig/:/root/.nomadnetwork/ -v /local/path/reticulumconfig/:/root/.reticulum/:rw ghcr.io/markqvist/nomadnet:master
```

# Please enter the commit message for your changes. Lines starting
# with '#' will be kept; you may remove them yourself if you want to.
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# Date:      Tue Apr 26 23:50:22 2022 +0100
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# On branch dockerfile
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#	new file:   .github/workflows/publish-container.yml
#	new file:   Dockerfile
#	modified:   README.md
#

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# Date:      Tue Apr 26 23:50:22 2022 +0100
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# On branch dockerfile
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#	new file:   .dockerignore
#	new file:   .github/workflows/publish-container.yml
#	new file:   Dockerfile
#	modified:   README.md
#

# Please enter the commit message for your changes. Lines starting
# with '#' will be kept; you may remove them yourself if you want to.
# An empty message aborts the commit.
#
# Date:      Tue Apr 26 23:50:22 2022 +0100
#
# On branch dockerfile
# Changes to be committed:
#	new file:   .dockerignore
#	new file:   .github/workflows/publish-container.yml
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.dockerignore

@@ -0,0 +1 @@
+.gitignore

.github/workflows/publish-container.yml

@@ -0,0 +1,42 @@
+name: Create and publish a Docker image
+
+on:
+  push:
+    branches: ['master']
+    tags: ['*.*.*']
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
+jobs:
+  build-and-push-image:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/metadata-action@98669ae865ea3cffbcbaa878cf57c20bbf1c6c38
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@ad44023a93711e3deb337508980b4b5e9bcdc5dc
+        with:
+          context: .
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}

Dockerfile

@@ -0,0 +1,24 @@
+FROM python:3.11-rc-alpine3.14 as build
+
+RUN apk add --no-cache build-base linux-headers libffi-dev cargo
+
+# Create a virtualenv that we'll copy to the published image
+RUN python -m venv /opt/venv
+ENV PATH="/opt/venv/bin:$PATH"
+RUN pip3 install setuptools-rust pyopenssl cryptography
+
+COPY . /app/
+RUN cd /app/ && python3 setup.py install
+
+# Use multi-stage build, as we don't need rust compilation on the final image
+FROM python:3.11-rc-alpine3.14
+
+LABEL org.opencontainers.image.documentation="https://github.com/jphastings/NomadNet#using-docker--running-a-daemon"
+
+ENV PATH="/opt/venv/bin:$PATH"
+COPY --from=build /opt/venv /opt/venv
+
+VOLUME /root/.reticulum
+VOLUME /root/.nomadnetwork
+
+ENTRYPOINT ["nomadnet"]

README.md

@@ -53,6 +53,28 @@ You can install Nomad Network on Android using Termux, but there's a few more co
 
 For a native Android application with a graphical user interface, have a look at [Sideband](https://unsigned.io/sideband).
 
+### Using docker / running a daemon
+
+Nomad Network is automatically published as a docker image on Github Packages. Image tags are one of either `master` (for the latest release) or the version number (eg `0.1.7`) for the specified version number (as tagged in this git repo).
+
+
+```sh
+$ docker pull ghcr.io/markqvist/nomadnet:master
+
+# Run nomadnet interactively without installing it (with default config)
+$ docker run -it ghcr.io/markqvist/nomadnet:master
+
+# Run nomadnet as a daemon, using config stored on the host machine in specific
+# directories, and allowing access to specific numbered ports openned by nomadnet
+# on the host machine on the same port numbers.
+$ docker run -d \
+  -v /local/path/nomadnetconfig/:/root/.nomadnetwork/ \
+  -v /local/path/reticulumconfig/:/root/.reticulum/ \
+  -p 37428:37428 \
+  -p 37429:37429 \
+  ghcr.io/markqvist/nomadnet:master
+```
+
 ## Help & Discussion
 
 For help requests, discussion, sharing ideas or anything else related to Nomad Network, please have a look at the [Nomad Network discussions pages](https://github.com/markqvist/Reticulum/discussions/categories/nomad-network).