Source additional env vars from Renviron.site.

This should enable R and RStudio to read dynamically created files. Part of berkeley-dsep-infra#5551.

deployments/datahub/images/default/Dockerfile

@@ -61,6 +61,11 @@ RUN curl --silent --location --fail ${SHINY_SERVER_URL} > /tmp/shiny-server.deb
 COPY Rprofile.site /usr/lib/R/etc/Rprofile.site
 # RStudio needs its own config
 COPY rsession.conf /etc/rstudio/rsession.conf
+# Enable customizations to Renviron.site
+COPY Renviron.site.append /tmp/Renviron.site.append
+RUN cat /tmp/Renviron.site.append >> /etc/R/Renviron.site && \
+    mkdir /etc/R/Renviron.site.d/ && \
+    rm /tmp/Renviron.site.append
 
 # R_LIBS_USER is set by default in /etc/R/Renviron, which RStudio loads.
 # We uncomment the default, and set what we wanna - so it picks up

deployments/datahub/images/default/Renviron.site.append

@@ -0,0 +1,20 @@
+
+## Source any extra Renviron files.
+#
+# Since there is an existing /etc/R/Renviron.site file, we append this. It lets
+# us easily add new code via extraFiles (or other z2jh-related magic)
+# without having to rebuild the image each time.
+
+
+# Get a list of files in the directory
+env_dir <- "/etc/R/Renviron.site.d/"
+env_files <- list.files(env_dir, full.names = TRUE)
+
+# Iterate over each file
+for (env_file in env_files) {
+    cat("Loading environment variables from:", env_file, "\n")
+
+    # Read and parse the environment file
+    readRenviron(env_file)
+}
+