array_index_out_of_bounds_exception for field name which is "." #21862
Description
Elasticsearch version: 5.0.1
Plugins installed: [] none
JVM version:1.8.0_111
OS version: Ubuntu 16.04
Description of the problem including expected versus actual behavior:
Steps to reproduce:
Without any custom templates or mapping, try this:
POST /test/test/1
{
"." : {
"foo" : {
"bar" : 123
}
}
}
and you will receive this 400 error:
{
"error" : {
"root_cause" : [
{
"type" : "mapper_parsing_exception",
"reason" : "failed to parse"
}
],
"type" : "mapper_parsing_exception",
"reason" : "failed to parse",
"caused_by" : {
"type" : "array_index_out_of_bounds_exception",
"reason" : "-1"
}
},
"status" : 400
}
It seems that a single . is not a valid field name (I cannot find documentation detailing this), and even if this is the case, the error is not very helpful.