Is it possible to update nested field by query? - elasticsearch

Question

I am using update by query plugin (https://github.com/yakaz/elasticsearch-action-updatebyquery/) to update documents by query.
In my case, there is nested field in document, the mapping is something like this:
"mappings": {
"mytype": {
"properties": {
"Myfield1": {
"type": "nested",
"properties": {
"field1": {
"type": "string"
},
"field2": {
"type": "long"
}
}
},
"Title": {
"type": "string"
}
}
}
}
Then I want to update the nested field Myfield1 by query with following request:
But unfortunately, it does not work.
{
"query": {
"match": {
"Title": "elasticsearch"
}
},
"script": "ctx._source.Myfield1 = [{'nestfield1':'foo blabla...','nestfield2':100},{'nestfield1':'abc...','nestfield2':200}]"
}
Does update by query support nested object?
BTW: any other ways to update document by query?
Is the update by query plugin the only choice?

Answer 1

This example uses _update_by_query
POST indexname/type/_update_by_query
{
"query": {
"match": {
"Title": "elasticsearch"
}
},
"script": {
"source": "ctx._source.Myfield1= params.mifieldAsParam",
"params": {
"mifieldAsParam": [
{
"nestfield1": "foo blabla...",
"nestfield2": 100
},
{
"nestfield1": "abc...",
"nestfield2": 200
}
]
},
"lang": "painless"
}
}

Answer 2

Nested elements need to be iterated in painless script to update values
POST /index/_update_by_query
{
"script": {
"source": "for(int i=0;i<=ctx._source['Myfield1'].size()-1;i++){ctx._source.Myfield1[i].field1='foo blabla...';ctx._source.Myfield1[i].field2=100}",
"lang": "painless"
},
"query": {
"match": {
"Title": "elasticsearch"
}
}
}
Nested elements value update if index is known
POST /index/_update_by_query
{
"script": {
"source": "ctx._source.Myfield1[0].field1='foo blabla...';ctx._source.Myfield1[0].field2=100;ctx._source.Myfield1[1].field1='abc...';ctx._source.Myfield1[1].field2=200;",
"lang": "painless"
},
"query": {
"match": {
"Title": "elasticsearch"
}
}
}

Answer 3

You can try with params, something like this:
"query" : {
"match_all" : {}
},
"script" : "ctx._source.Myfield1 = Myfield1;",
"params": {
"Myfield1": {
"nestfield1": "foo blabla..."
}
}
In my case I'm moving the data from not nested fields in nested fields. I need to add fake information to initialize the nested field. It looks like that:
"query" : {
"match_all" : {}
},
"script" : "ctx._source.Myfield1 = Myfield1; ctx._source.Myfield1.nestfield1 = ctx._source.Myfield1Nestfield1; ctx._source.Myfield1.nestfield2 = ctx._source.Myfield1Nestfield2;",
"params": {
"Myfield1": {
"nestfield1": "init_data"
}
}