title: How to index a .PDF file in ElasticSearch
body: <p>I am new to ElasticSearch. I have gone through very basic tutorial on creating Indexes. I do understand the concept of a indexing. I want ElasticSearch to search inside a .PDF File.  Based on my understanding of creating Indexes, it seems I need to read the .PDF file and extract all the keywords for indexing. But, I do not understand what steps I need to follow. How do I read .PFD file to extract keywords.</p>