NASA Earthdata download script patch to avoid re-downloading existing files

download.patch

--- ../download.sh
+++ ../download.sh
@@ -64,13 +64,33 @@
 fetch_urls() {
   if command -v curl >/dev/null 2>&1; then
       setup_auth_curl
+      row=0
       while read -r line; do
+        row=$((row + 1))
+
         # Get everything after the last '/'
         filename="${line##*/}"
 
         # Strip everything after '?'
         stripped_query_params="${filename%%\?*}"
 
+        # If file already exists, check whether it's a valid zip. If invalid, remove and re-download.
+        if [ -f "$stripped_query_params" ]; then
+            #echo "Found existing file '$stripped_query_params'. Validating..."
+            if command -v unzip >/dev/null 2>&1; then
+                if unzip -t "$stripped_query_params" >/dev/null 2>&1; then
+                    echo "$row: $stripped_query_params already downloaded"
+                    continue
+                else
+                    echo "$row: $stripped_query_params is invalid or corrupted; removing and re-downloading."
+                    rm -f "$stripped_query_params"
+                fi
+            else
+                exit_with_error "unzip not found. Please install unzip"
+            fi
+        fi
+
+        echo "$row: $stripped_query_params"
         curl -f -b "$cookiejar" -c "$cookiejar" -L --netrc-file "$netrc" -g -o $stripped_query_params -- $line && echo || exit_with_error "Command failed with error. Please retrieve the data manually."
       done;
   elif command -v wget >/dev/null 2>&1; then