Update Dockerfile

Dockerfile

@@ -1,5 +1,6 @@
 FROM rocker/r-base:latest
 
+# System deps for R pkgs + headless Chromium (for webshot2 PNG export)
 RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
     libcurl4-openssl-dev \
     libssl-dev \
@@ -9,25 +10,31 @@ RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y --no-ins
     libxrender1 \
     libxext6 \
     libnss3 \
-    libasound2 \
+    libglib2.0-0 \
+    libx11-6 \
+    libx11-xcb1 \
+    libxcb1 \
+    libxcomposite1 \
+    libxdamage1 \
+    libxfixes3 \
     libatk-bridge2.0-0 \
     libgtk-3-0 \
     libdrm2 \
     libgbm1 \
     fonts-liberation \
+    fonts-dejavu \
     chromium \
     ca-certificates \
-    && rm -rf /var/lib/apt/lists/*
+ && rm -rf /var/lib/apt/lists/*
 
-# Let chromote/webshot2 find Chromium
+# Let chromote/webshot2 find Chromium and use safe flags in containers
 ENV CHROME_BIN=/usr/bin/chromium
 ENV CHROMOTE_CHROME=/usr/bin/chromium
+ENV CHROMOTE_CHROME_ARGS="--no-sandbox --disable-dev-shm-usage"
 
-# Create app dir
 WORKDIR /app
 
-# Install R packages (keep this separate so it layers/caches nicely)
-# Add anything else you need here
+# R packages
 RUN install2.r --error --skipinstalled \
     shiny \
     shinydashboard \
@@ -39,11 +46,10 @@ RUN install2.r --error --skipinstalled \
     htmlwidgets \
     ggplot2
 
-
+# App code
 COPY . /app
 
 EXPOSE 7860
 
-# Run the Shiny app
-# This respects PORT if provided by the host, defaulting to 7860.
-CMD ["R", "--quiet", "-e", "options(shiny.port=as.integer(Sys.getenv('PORT', 7860)), shiny.host='0.0.0.0'); shiny::runApp('/app')"]
+# Run the Shiny app (uses $PORT if provided)
+CMD ["R", "--quiet", "-e", "options(shiny.port=as.integer(Sys.getenv('PORT', 7860)), shiny.host='0.0.0.0'); shiny::runApp('/app')"]