Add CI from template

.dockerignore

+*/node_modules
+*.log

.gitlab-ci.yml

+image: node:15.12-alpine3.13
+
+stages:
+  - test
+  - deploy
+
+test:
+  stage: test
+  script:
+  - cd docusaurus-site
+  - yarn install
+  - yarn build
+  rules:
+    - if: $CI_COMMIT_REF_NAME != $CI_DEFAULT_BRANCH
+
+pages:
+  stage: deploy
+  script:
+  - cd docusaurus-site
+  - yarn install
+  - yarn build
+  - mv ./build ../public
+  artifacts:
+    paths:
+    - public
+  rules:
+    - if: $CI_COMMIT_REF_NAME == $CI_DEFAULT_BRANCH

Dockerfile

+FROM node:lts
+
+WORKDIR /app/website
+
+EXPOSE 3000 35729
+#COPY ./docs /app/docs
+COPY ./docusaurus-site /app/website
+RUN yarn install
+
+CMD ["yarn", "start"]

docker-compose.yml

+version: "3"
+
+services:
+  docusaurus:
+    build: .
+    ports:
+      - 3000:3000
+      - 35729:35729
+    volumes:
+      - ./docs:/app/docs
+      - ./docusaurus-site/blog:/app/website/blog
+      - ./docusaurus-site/core:/app/website/core
+      - ./docusaurus-site/i18n:/app/website/i18n
+      - ./docusaurus-site/pages:/app/website/pages
+      - ./docusaurus-site/static:/app/website/static
+      - ./docusaurus-site/sidebars.json:/app/website/sidebars.json
+      - ./docusaurus-site/siteConfig.js:/app/website/siteConfig.js
+    working_dir: /app/website