_forcemerge API erroneously accepts JSON payloads and returns ambiguously positive response #29584
Description
Elasticsearch version (bin/elasticsearch --version): 6.2.3
Plugins installed: [X-Pack 6.2.3]
JVM version (java -version): OpenJDK Runtime Environment (build 1.8.0_161-b14)
OS version (uname -a if on a Unix-like system): Linux 44e7bb4d9f24 4.9.87-linuxkit-aufs #1 SMP Fri Mar 16 18:16:33 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux (Official Docker image running on MacOS 10.13.4)
Description of the problem including expected versus actual behavior: When attempting to execute a force merge operation passing the accepted parameters as a JSON payload, a response is returned to the user which ambiguously suggests the requested operation was successful. However, inspection of <index_name>/_segments shows no merge having taken place.
By contrast, when passing the parameter as a URL parameter, the merge takes place as expected.
Steps to reproduce:
- Trigger a force merge with a JSON payload of the desired parameters
POST <index_name>/_forcemerge
{
"max_num_segments": 1
}
- Receive positive looking response
{
"_shards": {
"total": 102,
"successful": 102,
"failed": 0
}
}
- Check the status
GET <index_name>/_segments
alternatively view Segment Count in X-Pack Monitoring
In order to actually trigger the merge, do the following:
POST <index_name>/_forcemerge?max_num_segments=1
Then verify with
GET <index_name>/_segments