Add file existence, and check is blank, and reorder the create README.md.

Change-Id: Ie2a039440143253b347495b46ae53b02d36d1c3d

generateModuleGraphs.sh

@@ -105,20 +105,30 @@ echo "$module_paths" | while read -r module_path; do
         file_name="dep_graph${module_path//:/_}" # Replace colons with underscores
         file_name="${file_name//-/_}" # Replace dashes with underscores
 
-        check_and_create_readme "$module_path" "$file_name"
-
         # Generate the .gv file in a temporary location
         # </dev/null is used to stop ./gradlew from consuming input which prematurely ends the while loop
         ./gradlew generateModulesGraphvizText \
           -Pmodules.graph.output.gv="/tmp/${file_name}.gv" \
           -Pmodules.graph.of.module="${module_path}" </dev/null
 
-        # Convert to SVG using dot, remove unnecessary comments, and reformat
-        dot -Tsvg "/tmp/${file_name}.gv" |
-          sed -e 's/<!--.*//g' -e 's/-->.*//g' | tr -d '\0' |
-          xmllint --format - \
-          > "docs/images/graphs/${file_name}.svg"
-        # Remove the temporary .gv file
+        # Check gv file's existence
+        if [ -e "/tmp/${file_name}.gv" ]; then
+          # Convert to SVG using dot, remove unnecessary comments
+          svg_cleared=`dot -Tsvg "/tmp/${file_name}.gv" | sed -e 's/<!--.*//g' -e 's/-->.*//g' | tr -d '\0'`
+
+          # Check file is empty or not, if not empty run xmllint to reformat
+          # Save as svg file
+          if [ -n "$svg_cleared" ]; then
+            echo $svg_cleared | xmllint --format - > "docs/images/graphs/${file_name}.svg"
+          else
+            echo $svg_cleared > "docs/images/graphs/${file_name}.svg"
+          fi
+
+          # Create README.md
+          check_and_create_readme "$module_path" "$file_name"
+
+          # Remove tmp files
           rm "/tmp/${file_name}.gv"
         fi
+    fi
 done