Génère une image Docker plus petite.

Dockerfile

@@ -14,12 +14,19 @@ RUN wget -nv -O /tmp/reveal.js.zip https://gitlab.irstea.fr/pole-is/tools/reveal
     && cd reveal.js \
     && ./pleasew build :reveal.js
 
-FROM node:${NODE_VERSION}-${DEBIAN_RELEASE}
+FROM node:${NODE_VERSION}-${DEBIAN_RELEASE}-slim
 
 COPY --from=builder /src/reveal.js/plz-out/gen/reveal.js /opt/reveal.js
 
 RUN apt-get update -yq \
     && apt-get install -yq --no-install-recommends \
+    ca-certificates \
+    fontconfig \
+    libjpeg62-turbo \
+    libx11-6 \
+    libxcb1 \
+    libxext6 \
+    libxrender1 \
     wget \
     xfonts-75dpi \
     xfonts-base \