In the previous chapter, we learned how to use the index API to manage indices and perform indexing and search operations on simple documents. We also looked at a number of APIs related to index persistence maintenance work. In this chapter, we will extend our understanding from the viewpoint of documents.

Elasticsearch is a document-oriented database, which means it stores the entire object or document. JavaScript Object Notation (JSON) is the document format used in the API. Not only is the document stored, but its content is also indexed to make it searchable. We will start by learning about the basics of a document and its life cycle and then we will learn how to access it. Then we continue with how to access multiple documents with the bulk API and migrating indices from the old version to the version 7.0. API.

By the end of this chapter, you'll learn the following topics:

• The Elasticsearch document life cycle
• Basic CRUD for single document management APIs
• Multi-document management APIs
• Migration from a multiple mapping types index