added a Dockerfile and gitlab-ci config

.dockerignore

@@ -0,0 +1,3 @@
+build
+node_modules
+.git

.gitlab-ci.yml

@@ -0,0 +1,21 @@
+image: egon0/docker-with-buildx-and-git
+
+variables:
+  DOCKER_HOST: tcp://docker:2375/
+  DOCKER_DRIVER: overlay2
+  DOCKER_TLS_CERTDIR: ""
+
+services:
+  - docker:dind
+
+build:
+  stage: build
+  variables:
+    IMAGE_TAG: $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG
+    D_IMAGE_TAG: egon0/openwrt-firmware-selector-multiarch:$CI_COMMIT_REF_SLUG
+    D_LATEST_TAG: egon0/openwrt-firmware-selector-multiarch:latest
+  script:
+    - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
+    - docker login -u $DOCKER_LOGIN -p $DOCKER_PASSWORD
+    - docker buildx create --use --name A$CI_COMMIT_SHORT_SHA
+    - docker buildx build --platform $BUILD_PLATFORMS --push -t $IMAGE_TAG -t $CI_REGISTRY_IMAGE:latest -t $D_IMAGE_TAG -t $D_LATEST_TAG .

Dockerfile

@@ -0,0 +1,24 @@
+FROM node:lts-alpine as build
+
+ARG HOMEPAGE="/"
+ARG ASU_URL="https://chef.libremesh.org"
+
+WORKDIR /usr/src/app
+
+COPY . .
+
+RUN cat src/config.ts
+RUN sed -i "s#asu_url: 'https://chef.libremesh.org'#asu_url: '$ASU_URL'#g" src/config.ts
+RUN cat src/config.ts
+# quick hack to get the multiarch builds running
+RUN yarn add @material-ui/icons
+# make the homepage config var configurable on buildtime via docker build-arg
+RUN yarn add json
+RUN node_modules/.bin/json -I -f package.json -e "this.homepage='$HOMEPAGE'"
+
+RUN yarn install
+RUN yarn build
+
+FROM nginx:stable-alpine AS release
+COPY --from=build /usr/src/app/build /usr/share/nginx/html
+