es，其實是有個內建的指令碼支援的，可以基於groovy指令碼實現各種各樣的複雜操作
基於groovy指令碼，如何執行partial update
es scripting module，我們會在高手進階篇去講解，這裡就只是初步講解一下
PUT /test_index/test_type/11
{
"num": 0,
"tags": []
}
（1）內建指令碼
POST /test_index/test_type/11/_update
{
"script" : "ctx._source.num+=1"
}
{
"_index": "test_index",
"_type": "test_type",
"_id": "11",
"_version": 2,
"found": true,
"_source": {
"num": 1,
"tags": []
}
}
（2）外部指令碼
ctx._source.tags+=new_tag
POST /test_index/test_type/11/_update
{
"script": {
"lang": "groovy",
"file": "test-add-tags",
"params": {
"new_tag": "tag1"
}
}
}
（3）用指令碼刪除文件
ctx.op = ctx._source.num == count ? 'delete' : 'none'
POST /test_index/test_type/11/_update
{
"script": {
"lang": "groovy",
"file": "test-delete-document",
"params": {
"count": 1
}
}
}
（4）upsert操作
POST /test_index/test_type/11/_update
{
"doc": {
"num": 1
}
}
{
"error": {
"root_cause": [
{
"type": "document_missing_exception",
"reason": "[test_type][11]: document missing",
"index_uuid": "6m0G7yx7R1KECWWGnfH1sw",
"shard": "4",
"index": "test_index"
}
],
"type": "document_missing_exception",
"reason": "[test_type][11]: document missing",
"index_uuid": "6m0G7yx7R1KECWWGnfH1sw",
"shard": "4",
"index": "test_index"
},
"status": 404
}
如果指定的document不存在，就執行upsert中的初始化操作；如果指定的document存在，就執行doc或者script指定的partial update操作
POST /test_index/test_type/11/_update
{
"script" : "ctx._source.num+=1",
"upsert": {
"num": 0,
"tags": []
}
}