Register .wdl as text MIME type for RStudio (PHP-130724)

RStudio misidentifies .wdl files containing 'import' statements as
binary/JavaScript, preventing users from opening them. Fix by
registering .wdl as text/x-wdl via the freedesktop shared-mime-info
system during post-startup, so extension-based MIME resolution takes
priority over content-based detection.

Only runs when rstudio-server is present, so non-RStudio apps are
unaffected.

Author: emmarogge

startupscript/post-startup.sh

@@ -218,6 +218,29 @@ sed -i '/user_allow_other/s/^#//g' /etc/fuse.conf
 
 source "${CLOUD_SCRIPT_DIR}/resource-mount.sh"
 
+###############################
+# RStudio file type configuration
+###############################
+# Register additional file types as text to prevent RStudio from
+# misidentifying them as binary (PHP-130724).
+if command -v rstudio-server &> /dev/null; then
+  emit "Registering additional MIME types for RStudio..."
+  # Add WDL (Workflow Description Language) MIME type so RStudio
+  # recognizes .wdl files as text instead of binary.
+  cat > /usr/share/mime/packages/wdl.xml << 'MIME_EOF'
+<?xml version="1.0" encoding="UTF-8"?>
+<mime-info xmlns="http://www.freedesktop.org/standards/shared-mime-info">
+  <mime-type type="text/x-wdl">
+    <comment>Workflow Description Language</comment>
+    <glob pattern="*.wdl"/>
+  </mime-type>
+</mime-info>
+MIME_EOF
+  if command -v update-mime-database &> /dev/null; then
+    update-mime-database /usr/share/mime
+  fi
+fi
+
 ###############################
 # cloud platform specific setup
 ###############################