提炼:

很简洁，无需提炼

正文:

If all you want to do is to check whether a document exists-you’re not interested in the content at all-then use the HEAD method instead of the GET method. HEAD requests don’t return a body, just HTTP headers:

curl -i -XHEAD http://localhost:9200/website/blog/123

Elasticsearch will return a 200 ok status code if the document exists;

HTTP/1.1 200 OK Content-Type: text/plain; charset=UTF-8 Content-Length: 0

And a 404 Not Found if it doesn’t exist:

curl -i -XHEAD http://localhost:9200/website/blog/124

HTTP/1.1 404 Not Found Content-Type: text/plain; charset=UTF-8 Content-Length: 0

Of course, just because a document didn’t exist when you checked it, doesn’t mean that it won’t exist a millisecond later: another process might create the document in the meantime.