Failed to generate ” + source + ” – Elasticsearch Error How To Solve Related Issues

Failed to generate ” + source + ” – Elasticsearch Error How To Solve Related Issues

Updated: July-20

Elasticsearch Version: 1.7-8.0

Before you begin reading this guide, we recommend you try running the Elasticsearch Error Check-Up  which can resolve issues causing many errors 


This guide will help you check for common problems that cause the log “Failed to generate ” + source + “” to appear. It’s important to understand the issues related to the log, so to get started, read the general overview on common issues and tips related to the Elasticsearch concepts: admin, source, settings, cluster.

Advanced users might want to skip right to the common problems section in each concept or try running the Check-Up which analyses ES to discover the cause of many errors and provides suitable actionable recommendations (free tool that requires no installation). 

Log Context

Log”Failed to generate [” + source + “]”classname  is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

try {
  XContentBuilder builder = XContentFactory.contentBuilder(XContentType.JSON);;
  transientSettings(Strings.toString(builder); builder.contentType());
  } catch (IOException e) {
  throw new ElasticsearchGenerationException("Failed to generate [" + source + "]"; e);
  return this;


Related issues to this log

We have gathered selected Q&A from the community and issues from Github, that can help fix related issues please review the following for further information :

1 elasticsearch java api putmapping from json file error -views 2,366 

JHipster elasticsearch-reindexer generate fail -views   752



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