NEXUS App Stack (contrib)

Requirements

In order to be able to work with the NEXUS app stack code, the following requirements must be met.

Environment variables

Add the following environment variables to your .env file:

NEXUS_CONTRIB_REPOSITORY_BRANCH=github.com/ETH-NEXUS/nexus-app-stack-contrib.git@main
NEXUS_CONTRIB_DOWNLOAD_SCRIPT=raw.githubusercontent.com/ETH-NEXUS/nexus-app-stack-contrib/main/download.sh

Docker Compose

Integrate the following lines in your Docker Compose file version 3.9:

version: "3.9"

services:
  service1:
    build:
      args:
        ENVIRONMENT: "Production" # Only needs to be defined in your Docker Compose production file.
        NEXUS_CONTRIB_REPOSITORY_BRANCH: "$NEXUS_CONTRIB_REPOSITORY_BRANCH"
        NEXUS_CONTRIB_DOWNLOAD_SCRIPT: "$NEXUS_CONTRIB_DOWNLOAD_SCRIPT"
    volumes:
      - ${NEXUS_CONTRIB_BIND:-/dev/null:/.no_nexus_contrib_bind}

Dockerfiles

Basics

• The git command must be available during the Docker image build. On Alpine Linux you can install Git with the following command:

  RUN apk add --update --no-cache git
  

• The Dockerfile commands like COPY requirements.txt / or COPY app/package.json /app should be executed before the Dockerfile commands relevant for the NEXUS app stack because it is convenient that a dependency version update triggers a refresh of the NEXUS app stack repository.

Python/Django (api subdirectory)

All NEXUS app stack Python libraries and/or Django apps that you want to use in your project must be added to the PYTHONPATH environment variable so that Python is aware of the sources. This variable is also used during the NEXUS app stack bootstrap to download/clone the sources from the repository (see next step).

Define the environment:

ARG ENVIRONMENT
ARG NEXUS_CONTRIB_REPOSITORY_BRANCH
ARG NEXUS_CONTRIB_DOWNLOAD_SCRIPT
ENV PYTHONPATH="$PYTHONPATH:\
/nexus-app-stack-contrib/api/django-feature-1:\
/nexus-app-stack-contrib/api/django-feature-2"

NEXUS App Stack api bootstrap command for the...

• Alpine Linux BusyBox Almquist shell:

  RUN export ENVIRONMENT=$ENVIRONMENT BRANCH=$NEXUS_CONTRIB_REPOSITORY_BRANCH && \
    sh <(wget -q -O - https://$NEXUS_CONTRIB_DOWNLOAD_SCRIPT || echo false) \
    $(echo "$PYTHONPATH" | sed "s/:\/nexus-app-stack-contrib\// /g")
  

  See also the Dockerfile.TINY_IMAGE template.

• Bash shell:

  RUN export ENVIRONMENT=$ENVIRONMENT BRANCH=$NEXUS_CONTRIB_REPOSITORY_BRANCH && \
    bash -c "$(wget -q -O - https://$NEXUS_CONTRIB_DOWNLOAD_SCRIPT || echo false)" '' \
    $(echo "$PYTHONPATH" | sed "s/:\/nexus-app-stack-contrib\// /g")
  

Vue/Quasar (ui subdirectory)

All NEXUS app stack UI packages that you want to use in the project are specified in the last line of the RUN command.

RUN export ENVIRONMENT=$ENVIRONMENT BRANCH=$NEXUS_CONTRIB_REPOSITORY_BRANCH && \
  sh <(wget -q -O - https://$NEXUS_CONTRIB_DOWNLOAD_SCRIPT || echo false) \
  ui/vue-fileupload ui/vue-viewer

Note: The command was tested with an Alpine Linux BusyBox Almquist shell.

See also the Dockerfile.TINY_IMAGE template.

Reference the code

Python

You can reference NEXUS app stack code in the requirements.txt file like this:

-e /nexus-app-stack-contrib/api/django-feature

If you do not need to edit the code locally, you can reference it directly (in this case you do not actually need any NEXUS app stack specific Dockerfile adjustments):

django-feature @ git+https://${NEXUS_CONTRIB_REPOSITORY_BRANCH}#subdirectory=api/django-feature

JavaScript

You can reference NEXUS app stack code in the package.json file like this:

{
  "dependencies": {
    "@nexus-app-stack-contrib/vue-feature": "link:../nexus-app-stack-contrib/ui/vue-feature"
  }
}

Unfortunately, Yarn does not support references to repository subdirectories. Therefore, the NEXUS app stack specific Dockerfile adjustments are always necessary.

In order that the linked package finds all its dependencies, an installation of these dependencies for each of the linked package is necessary. This can be done in the entrypoint.sh:

#!/usr/bin/env sh

set -euo pipefail

yarn install --cwd /nexus-app-stack-contrib/ui/vue-feature
yarn install --cwd /nexus-app-stack-contrib/ui/vue-another-feature
yarn install --cwd /nexus-app-stack-contrib/ui/vue-yet-another-feature
yarn install

yarn dev --host 0.0.0.0 --port 8077

Development

Clone the "nexus-app-stack-contrib" repository to a local directory next to your project repository directory:

git clone https://github.com/ETH-NEXUS/nexus-app-stack-contrib.git -b main

The repository directory will be bind into your Docker containers. This approach allows you to develop the app stack part alongside your project code without having to commit and deploy every change. The following environment (.env) variable defines this bind:

NEXUS_CONTRIB_BIND=../nexus-app-stack-contrib:/nexus-app-stack-contrib

Testing

download.sh

BRANCH=github.com/ETH-NEXUS/nexus-app-stack-contrib.git@main \
  sh download.sh api/django-feature