Dockerfile

You can easily deploy your Dockerfile using the ale Dockerfile template.

ale presets and templates use minimal libraries to optimize resource usage. If your application requires additional libraries not included in our default presets, such as Windows or Chrome libraries, you need to use the Dockerfile template. Please refer to our example code for creating your custom Dockerfile.

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Select Template and Repository

On the dashboard, click or ⌘ + K to open the deployment modal. Select the Dockerfile template, Then choose a GitHub repository from the dropdown or input a Git repository URL in the Git URL tab.

Configuration and Deployment

Basic Settings

• Environment variables(ENV): Environment variables passed to containers at runtime

• Build arguments(ARG): Build-time variables used during Docker image construction

• Port: Container port mapping configuration (corresponds to Docker’s -p or —publish flag)

• Health Check: endpoint used to verify container health status

• Start commands: Commands executed when the container starts

More Options

• Dockerfile text: Enter the complete contents of the Dockerfile

• Build Labels(LABEL): Custom metadata for your Docker image (e.g., version, description)

• uid: User ID for executing processes within the container (default: 1000)

• gid: Group ID for process ownership within the container (default: 1000)

• Update strategy

  • Rolling Update: Deploy new version incrementally while maintaining service availability. Requires sufficient node resources
  • Recreate: Stop all instances before deploying new version. Results in service downtime

• Shell: Specify the shell for container runtime execution (sh, bash, zsh, etc.)

Resource and Deployment

• Resource Type: Select between On-demand or Spot instance types

• CPU: Maximum vCPU resource for the service. Minimum vCPU means 0.1 vCPU

• Memory: Maximum memory size your service can use

• Replica: Number of service replicas for high availability and load balancing

• Deploy: Click Deploy

If deployment fails due to resource limitations, see the Space and Resource Management page to add resources to your space.

Logs & Terminal

Click the icon in the service card or service page to check deployment/runtime logs or access the terminal.

Metrics

You can view service metrics in the Metrics tab of the service page.

Update

When you update your code or modify resource settings, click Deploy at the bottom of the service settings page to apply these changes with a new deployment.

To set up automated deployments using GitHub Actions, see the GitHub Actions page.

Rollback

To restore your service to a previous version, navigate to the deployment history tab in the service page.

Check the commit messages in the deployment history to ensure you’re rolling back to the intended version.

Example Code by Language

Node.js - Express

Go to Github Repository

# Install dependencies
FROM node:16-buster
WORKDIR /app
COPY package*.json ./ 
RUN npm ci --only=production

ENV NODE_ENV production

COPY . .

# "node" user already exists in node image with uid/gid 1000
USER node

EXPOSE 3000
CMD ["npm", "start"]

React

Go to Github Repository

# Project build
FROM node:16-buster AS builder
WORKDIR /app
COPY package*.json .
RUN npm ci
COPY . .
RUN npm run build

# Production runtime - nginx
FROM nginxinc/nginx-unprivileged:1.23 AS runner
WORKDIR /usr/share/nginx/html
COPY --from=builder /app/build .

EXPOSE 3000
CMD ["nginx", "-g", "daemon off;"]

Python Flask

Go to Github Repository

FROM python:3.9-slim-buster

ENV PYTHONDONTWRITEBYTECODE=1
ENV PYTHONUNBUFFERED 1

ARG UID=1000
ARG GID=1000

RUN groupadd -g "${GID}" python \
  && useradd --create-home --no-log-init -u "${UID}" -g "${GID}" python
WORKDIR /home/python

COPY --chown=python:python requirements.txt requirements.txt
RUN pip3 install -r requirements.txt

# USER change must be written after pip package installation script
USER python:python
ENV PATH="/home/${USER}/.local/bin:${PATH}"
COPY --chown=python:python . .

ARG FLASK_ENV

ENV FLASK_ENV=${FLASK_ENV}

EXPOSE 5000

# Modify WSGI, port number, module name, etc. according to each source code for deployment
CMD ["gunicorn", "-b", "0.0.0.0:5000", "app:app"]

Spring Boot

Go to Github Repository

# Build executable jar with JDK image
FROM eclipse-temurin:17-alpine AS build
RUN apk add --no-cache bash

WORKDIR /app

COPY gradlew .
COPY gradle gradle
COPY build.gradle settings.gradle ./
# COPY build.gradle.kts settings.gradle.kts ./    Apply .kts extension for Kotlin

RUN ./gradlew dependencies --no-daemon

COPY . .

RUN chmod +x ./gradlew

RUN ./gradlew bootJar --no-daemon

# Apply JRE image to run jar
FROM eclipse-temurin:17-jre-alpine
WORKDIR /app

RUN addgroup -g 1000 worker && \
    adduser -u 1000 -G worker -s /bin/sh -D worker

COPY --from=build --chown=worker:worker /app/build/libs/*.jar ./main.jar

USER worker:worker

EXPOSE 8080

ENTRYPOINT ["java", "-jar", "main.jar"]

Spring Boot(Multi-module)

Go to Github Repository

# Build executable jar with JDK image
FROM eclipse-temurin:17-alpine AS build
RUN apk add --no-cache bash

WORKDIR /app

COPY gradlew .
COPY gradle gradle
COPY build.gradle settings.gradle ./
# COPY build.gradle.kts settings.gradle.kts ./    Apply .kts extension for Kotlin

RUN ./gradlew dependencies --no-daemon

COPY . .

RUN chmod +x ./gradlew

RUN ./gradlew bootJar :api:bootJar --no-daemon
# RUN ./gradlew bootJar :<main module name>:bootJar --no-daemon

# Apply JRE image to run jar
FROM eclipse-temurin:17-jre-alpine
WORKDIR /app

RUN addgroup -g 1000 worker && \
    adduser -u 1000 -G worker -s /bin/sh -D worker

COPY --from=build --chown=worker:worker /app/api/build/libs/*.jar ./main.jar
# COPY --from=build --chown=worker:worker /app/<main module name>/build/libs/*.jar ./main.jar

USER worker:worker

EXPOSE 8080

ENTRYPOINT ["java", "-jar", "main.jar"]

Spring Boot CRUD App(Gradle)

Go to Github Repository

# Build
FROM eclipse-temurin:17-alpine AS build
RUN apk add --no-cache bash

WORKDIR /app

COPY gradlew .
COPY gradle gradle
COPY build.gradle.kts settings.gradle.kts ./

RUN ./gradlew dependencies --no-daemon

COPY . .

RUN chmod +x ./gradlew

RUN ./gradlew build --no-daemon -x test


# Runtime
FROM eclipse-temurin:17-jre-alpine AS runtime
WORKDIR /app

RUN addgroup -g 1000 worker && \
    adduser -u 1000 -G worker -s /bin/sh -D worker

COPY --from=build --chown=worker:worker /app/build/libs/*.jar ./main.jar

USER worker:worker

ENV PROFILE=${PROFILE}

EXPOSE 8080

ENTRYPOINT ["java", "-Dspring.profiles.active=${PROFILE}", "-jar", "main.jar"]

Spring Boot CRUD App(Maven)

Go to Github Repository

# Build
FROM eclipse-temurin:17-alpine AS build
RUN apk add --no-cache bash

WORKDIR /app

COPY mvnw .
COPY .mvn .mvn
COPY pom.xml .

RUN ./mvnw dependency:go-offline -B

COPY . .

RUN chmod +x ./mvnw

RUN ./mvnw package -DskipTests


# Runtime
FROM eclipse-temurin:17-jre-alpine as runtime

WORKDIR /app

RUN addgroup -g 1000 worker && \
    adduser -u 1000 -G worker -s /bin/sh -D worker

COPY --from=build --chown=worker:worker /app/target/*.jar ./main.jar

USER worker:worker

ENV PROFILE=${PROFILE}

EXPOSE 8080

ENTRYPOINT ["java", "-Dspring.profiles.active=${PROFILE}", "-jar", "main.jar"]