Indexing a document (POST/PUT) in Elasticsearch - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the result of this indexing request?

Given the following Elasticsearch indexing request, what will be the status in the response if the document is successfully indexed?

Elasticsearch

POST /library/_doc/1
{
  "title": "Learn Elasticsearch",
  "author": "Jane Doe",
  "year": 2023
}

A {"_index":"library","_id":"1","result":"deleted"}

B {"_index":"library","_id":"1","result":"updated"}

C {"_index":"library","_id":"1","result":"created"}

D {"_index":"library","_id":"1","result":"error"}

💡 Hint

When you use POST with a new document ID, Elasticsearch creates the document.

Using POST with a new document ID creates the document, so the result field in the response is 'created'.

❓ Predict Output

intermediate

What happens when you PUT a document with an existing ID?

Consider this request to update a document by ID using PUT. What will the 'result' field show if the document already exists?

Elasticsearch

PUT /library/_doc/1
{
  "title": "Mastering Elasticsearch",
  "author": "Jane Doe",
  "year": 2024
}

A {"_index":"library","_id":"1","result":"updated"}

B {"_index":"library","_id":"1","result":"created"}

C {"_index":"library","_id":"1","result":"noop"}

D {"_index":"library","_id":"1","result":"deleted"}

💡 Hint

PUT with an existing ID replaces the document, so it updates.

PUT with an existing document ID replaces the document, so the result is 'updated'.

🧠 Conceptual

advanced

Which HTTP method is idempotent for indexing documents?

In Elasticsearch, which HTTP method ensures that multiple identical requests have the same effect on the document store?

A PUT

B GET

C POST

D DELETE

💡 Hint

Idempotent means the same request repeated does not change the result after the first time.

PUT is idempotent because sending the same document with the same ID multiple times results in the same state.

❓ Predict Output

advanced

What error occurs if you try to index a document with invalid JSON?

What error will Elasticsearch return if you send this indexing request with malformed JSON?

Elasticsearch

POST /library/_doc
{
  "title": "Invalid JSON",
  "author": "John Doe",
  "year": 2023
}

A {"error":{"type":"version_conflict_engine_exception","reason":"version conflict"}}

B {"error":{"type":"json_parse_exception","reason":"Unexpected character ('}' at position...)"}}

C {"error":{"type":"index_not_found_exception","reason":"no such index"}}

D {"result":"created"}

💡 Hint

Malformed JSON causes a parsing error before indexing.

Elasticsearch returns a json_parse_exception when the JSON is invalid.

🧠 Conceptual

expert

What is the difference in behavior between POST and PUT when indexing documents without specifying an ID?

In Elasticsearch, when you index a document without specifying an ID, what is the difference in behavior between using POST and PUT methods?

A Both POST and PUT require an ID and will fail if none is specified.

B PUT auto-generates an ID; POST requires an ID and will fail without it.

C Both POST and PUT auto-generate IDs if none are specified.

D POST auto-generates an ID; PUT requires an ID and will fail without it.

💡 Hint

Think about which method allows auto ID generation.

POST allows auto-generation of document IDs when none is provided; PUT requires an explicit ID and will fail if missing.