feat: add Docker release workflow docs

Author: taariq

Dockerfile

@@ -1,18 +1,20 @@
 # syntax=docker/dockerfile:1
 
-FROM rust:1.82-slim AS builder
-WORKDIR /app
+FROM debian:bookworm-slim AS downloader
+ARG VERSION=latest
+ENV BINARY_NAME=database-replicator-linux-x64-binary
+ENV RELEASE_ROOT=https://github.com/serenorg/database-replicator/releases
 
-# Install build dependencies for OpenSSL / libpq bindings
-RUN apt-get update && \
-    apt-get install -y --no-install-recommends pkg-config libssl-dev libpq-dev && \
-    rm -rf /var/lib/apt/lists/*
+RUN apt-get update && apt-get install -y --no-install-recommends curl ca-certificates && rm -rf /var/lib/apt/lists/*
 
-# Cache dependencies
-COPY Cargo.toml Cargo.lock ./
-COPY src ./src
-COPY README.md .
-RUN cargo build --release --bin database-replicator
+RUN set -eux; \
+    if [ "$VERSION" = "latest" ]; then \
+        URL="$RELEASE_ROOT/latest/download/$BINARY_NAME"; \
+    else \
+        URL="$RELEASE_ROOT/download/$VERSION/$BINARY_NAME"; \
+    fi; \
+    curl -fL "$URL" -o /tmp/database-replicator && \
+    chmod +x /tmp/database-replicator
 
 FROM debian:bookworm-slim
 LABEL org.opencontainers.image.title="database-replicator" \
@@ -24,7 +26,7 @@ RUN apt-get update && \
     rm -rf /var/lib/apt/lists/* && \
     useradd -m replicator
 
-COPY --from=builder /app/target/release/database-replicator /usr/local/bin/database-replicator
+COPY --from=downloader /tmp/database-replicator /usr/local/bin/database-replicator
 USER replicator
 ENTRYPOINT ["database-replicator"]
 CMD ["--help"]

README.md

@@ -233,18 +233,22 @@ The binary will be available at `target/release/database-replicator`.
 
 ### Docker Image
 
-Build a container image with the latest source:
+Build an image from the latest GitHub release (default) or a specific tag:
 
 ```bash
+# latest release asset
 docker build -t serenorg/database-replicator:latest .
+
+# specific version
+docker build --build-arg VERSION=v5.3.20 -t serenorg/database-replicator:v5.3.20 .
 ```
 
 Run the CLI inside the container (pass connection strings via arguments or environment variables):
 
 ```bash
-docker run --rm -it \
-  serenorg/database-replicator:latest \
-  validate --source "postgresql://user:pass@source/db" --target "postgresql://user:pass@target/db"
+docker run --rm -it serenorg/database-replicator:latest \
+  validate --source "postgresql://user:pass@source/db" \
+           --target "postgresql://user:pass@target/db"
 ```
 
 Mount local config files if needed:
@@ -253,7 +257,7 @@ Mount local config files if needed:
 docker run --rm -it \
   -v "$PWD:/work" \
   serenorg/database-replicator:latest \
-  init --source @/work/source.txt --target @/work/target.txt
+  init --source "$(cat /work/source.txt)" --target "$(cat /work/target.txt)"
 ```
 
 ### Prerequisites