A Dockerfile iku berkas teks sing duwe instruksi kanggo membangun Docker image — iku njlentrehke base image, dependensi, berkas sing kudu disalin, lan cara njalanke aplikasi. Iku gawenke build image bisa diulang lan bisa dikontrol versi.
A basic Dockerfile
# FROM — the base image to build on
FROM node:20-alpine
# WORKDIR — set the working directory inside the image
WORKDIR /app
# COPY dependency files first (for better layer caching)
COPY package*.json ./
# RUN — execute a command during the BUILD (install dependencies)
RUN npm install
# COPY the rest of the application code
COPY . .
# EXPOSE — document the port the app listens on
EXPOSE 3000
# CMD — the command to run when a CONTAINER starts
CMD ["node", "server.js"]
