Dockerfile

# ---- Base image (default fallback) ----
ARG BASE_IMAGE
FROM ${BASE_IMAGE:-openjdk:21-jdk-slim}

# ---- Runtime arguments ----
ARG JAR_FILENAME
ARG JAR_FILE_PATH

ENV JAR_FILENAME=${JAR_FILENAME:-app.jar}
ENV JAR_FILE_PATH=${JAR_FILE_PATH:-build/libs}
ENV JAR_FULL_PATH=$JAR_FILE_PATH/$JAR_FILENAME

# ---- Set runtime ENV for Spring Boot to bind port
ARG SERVER_PORT
ENV SERVER_PORT=${SERVER_PORT:-4550}

# ---- Dependencies ----
RUN apt-get update \
    && apt-get install -y curl \
    && rm -rf /var/lib/apt/lists/*

# ---- Application files ----
COPY $JAR_FULL_PATH /opt/app/app.jar
COPY lib/applicationinsights.json /opt/app/

# ---- Permissions ----
RUN chmod 755 /opt/app/app.jar

# ---- Runtime ----
EXPOSE 4550

# Documented runtime configuration
# JWT secret for token verification (Base64-encoded HS256 key)
ENV JWT_SECRET_KEY="it-must-be-a-string-secret-at-least-256-bits-long"

CMD ["java", "-jar", "/opt/app/app.jar"]