diff --git a/vsellier/elasticsearch/convert-fields.sh b/vsellier/elasticsearch/convert-fields.sh
new file mode 100644
index 0000000..e8f4ccb
--- /dev/null
+++ b/vsellier/elasticsearch/convert-fields.sh
@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+# set -x
+set -e
+
+export ES_NODE="192.168.100.61:9200"
+
+export INDEX=$1
+
+cat > /tmp/reindex.json <<EOF
+{
+  "source": {
+    "index": "${INDEX}"
+  },
+  "dest": {
+    "index": "${INDEX}.migrated"
+  },
+  "script": {
+    "inline": "ctx._source.bytes = ctx._source.bytes instanceof java.lang.String ? Long.parseLong(ctx._source.bytes) : ctx._source.bytes; ctx._source.response = ctx._source.response instanceof java.lang.String ? Long.parseLong(ctx._source.response) : ctx._source.response;"
+  }
+}
+EOF
+
+DOCS_TO_MIGRATE=$(curl -s http://$ES_NODE/$INDEX/_stats  | jq '._all.primaries.docs.count')
+
+echo "$DOCS_TO_MIGRATE documents to migrate"
+
+curl -XPOST -H "Content-Type: application/json" http://$ES_NODE/_reindex\?pretty -d @/tmp/reindex.json
+
+echo "Refreshing index stats"
+curl -XPOST http://$ES_NODE/$INDEX.migrated/_refresh
+echo
+
+DOCS_MIGRATED=$(curl -s http://$ES_NODE/$INDEX.migrated/_stats  | jq '._all.primaries.docs.count')
+
+echo "$DOCS_MIGRATED / $DOCS_TO_MIGRATE documents migrated"
+if [ "${DOCS_MIGRATED}" != "${DOCS_TO_MIGRATE}" ]; then
+  echo "ERROR: The number of documents are not equals"
+  echo "Migration stopped, the .migrated index is left in place"
+  exit 1
+fi
+
+echo
+echo "Removing old index"
+curl -f -XDELETE http://$ES_NODE/$INDEX\?pretty
+
+cat > /tmp/rename.json <<EOF
+{
+  "source": {
+    "index": "${INDEX}.migrated"
+  },
+  "dest": {
+    "index": "${INDEX}"
+  }
+}
+EOF
+
+echo
+echo "Renaming $INDEX.migrated to $INDEX..."
+curl -f -XPOST -H "Content-Type: application/json" http://$ES_NODE/_reindex\?pretty -d @/tmp/rename.json
+
+echo
+echo "Removing $INDEX.migrated..."
+curl -f -XDELETE http://$ES_NODE/$INDEX.migrated\?pretty
+
+echo
+echo "Done"
+