Add Dockerfile for containerized data generation

Author: midwire

Dockerfile

@@ -0,0 +1,21 @@
+FROM ruby:3.4-slim
+
+RUN apt-get update && \
+    apt-get install -y --no-install-recommends build-essential git pkg-config && \
+    rm -rf /var/lib/apt/lists/*
+
+WORKDIR /app
+
+COPY Gemfile Gemfile.lock free_zipcode_data.gemspec .ruby-version ./
+COPY lib/free_zipcode_data/version.rb lib/free_zipcode_data/version.rb
+RUN git init && git add . && \
+    bundle config set --local without development && \
+    bundle install
+
+COPY . .
+RUN git add .
+
+ENV COUNTRY=""
+VOLUME /output
+
+ENTRYPOINT ["./docker-entrypoint.sh"]