I can't seem to understand the QueryDSL for facets in elastic search. Below are my query object, and the mapping for my tags array. I'm trying to get these to put in a faceted navigation based on tags. Each "element" will have multiple tags associated in the tags array [Not all elements will have tags. Some will have an empty array.]. Each tag is an object with id and tag properties.
I've tried the nested facet approach and get the error that "tags is not nested", so then I try this below. I don't receive an error, but there is no facets object in the return JSON. I've been using this page for help: http://www.elasticsearch.org/guide/reference/api/search/facets/index.html.
Can anyone help me to format this correctly and understand the organization of these? I appreciate any help!
// this is my query object
{
"sort":{ "created_at":{ "order":"desc" } },
"query":{
"constant_score":{
"filter":{
"and":[
{ "missing":{ "field":"parent_id" } },
{ "missing":{ "field":"wall_id" } },
{ "term":{ "active":true } }
]
}
}
},
"facets":{
"tags":{ "terms":{ "field":"tags.tag" } }
}
}
// this is the mapping for the tags array
"tags":{
"type":"nested",
"include_in_parent":true,
"properties":{
"id":{ "type":"integer" },
"tag":{ "type":"string" }
}
},
I've tried hard to replicate this (using 0.18.5) but without any luck. Some details below. The first example tries to replicate what you describe. The second doesn't map tags as include_in_parent and uses the "nested" field in the facet request. As you can see, in both cases the facet is returned.
This leads me to believe that there is either something wrong with the rest of the mappings or some document (not the sample one you provided) that is causing issues.
When you tried the nested approach, perhaps you used "nested":"tags.tag" instead of "nested":"tags"?
(Un)Successful attempt #1:
Create index with mappings:
$ curl -XPOST 'http://localhost:9200/testindex/' -d '{
"mappings": {
"element": {
"properties": {
"tags": {
"type": "nested",
"include_in_parent": true,
"properties": {
"id": {
"type": "integer"
},
"tag": {
"type": "string"
}
}
}
}
}
}
}'
Index document:
$ curl -XPOST 'http://localhost:9200/testindex/element' -d '{
"element_id": 4682,
"parent_id": null,
"wall_id": null,
"username": "John Doe",
"avatar": "56f1bb0a96d02b90e5915ff38ea189ec.jpg",
"title": "Easy Chart is a great easy comparison chart maker for math and...",
"description": "<p>Easy Chart is a great easy comparison chart maker for math and science skills. It even allows you to pick the appropriate chart type.</p>",
"groups": [
{
"id": 6,
"name": "Fourth Grade (All Subjects)",
"name_short": "4th Grade"
},
{
"id": 17,
"name": "Eighth Grade Science",
"name_short": "8th Science"
},
{
"id": 13,
"name": "Seventh Grade Science",
"name_short": "7th Science"
},
{
"id": 9,
"name": "Sixth Grade Science",
"name_short": "6th Science"
}
],
"tags": [
{
"id": 33,
"tag": "iPad"
},
{
"id": 32,
"tag": "iPod"
}
],
"webpages": [],
"videos": [],
"documents": [],
"photos": [],
"reports": [],
"bookmarks": [],
"likes": [],
"dislikes": [],
"element_type": "Post",
"active": true,
"deleted": false,
"updated_at": "2011-11-27T21:37:38-0600",
"created_at": 1322451458000,
"created_at_formatted": "2 weeks ago"
}'
Search:
$ curl -XPOST 'http://localhost:9200/testindex/element/_search' -d '{
"sort":{ "created_at":{ "order":"desc" } },
"query":{
"constant_score":{
"filter":{
"and":[
{ "missing":{ "field":"parent_id" } },
{ "missing":{ "field":"wall_id" } },
{ "term":{ "active":true } }
]
}
}
},
"facets":{
"tags":{ "terms":{ "field":"tags.tag" } }
}
}'
Result:
{
"took": 4,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 1,
"max_score": null,
"hits": [
{
"_index": "testindex",
"_type": "element",
"_id": "RZK41LngTKOhMUS6DXRi7w",
"_score": null,
"_source": {
"element_id": 4682,
"parent_id": null,
"wall_id": null,
"username": "John Doe",
"avatar": "56f1bb0a96d02b90e5915ff38ea189ec.jpg",
"title": "Easy Chart is a great easy comparison chart maker for math and...",
"description": "<p>Easy Chart is a great easy comparison chart maker for math and science skills. It even allows you to pick the appropriate chart type.</p>",
"groups": [
{
"id": 6,
"name": "Fourth Grade (All Subjects)",
"name_short": "4th Grade"
},
{
"id": 17,
"name": "Eighth Grade Science",
"name_short": "8th Science"
},
{
"id": 13,
"name": "Seventh Grade Science",
"name_short": "7th Science"
},
{
"id": 9,
"name": "Sixth Grade Science",
"name_short": "6th Science"
}
],
"tags": [
{
"id": 33,
"tag": "iPad"
},
{
"id": 32,
"tag": "iPod"
}
],
"webpages": [],
"videos": [],
"documents": [],
"photos": [],
"reports": [],
"bookmarks": [],
"likes": [],
"dislikes": [],
"element_type": "Post",
"active": true,
"deleted": false,
"updated_at": "2011-11-27T21:37:38-0600",
"created_at": 1322451458000,
"created_at_formatted": "2 weeks ago"
},
"sort": [
1322451458000
]
}
]
},
"facets": {
"tags": {
"_type": "terms",
"missing": 0,
"total": 2,
"other": 0,
"terms": [
{
"term": "ipod",
"count": 1
},
{
"term": "ipad",
"count": 1
}
]
}
}
}
(Un)Successful attempt #2:
Create index with mappings:
$ curl -XPOST 'http://localhost:9200/testindex2/' -d '{
"mappings": {
"element": {
"properties": {
"tags": {
"type": "nested",
"include_in_parent": false,
"properties": {
"id": {
"type": "integer"
},
"tag": {
"type": "string"
}
}
}
}
}
}
}'
Index document:
$ curl -XPOST 'http://localhost:9200/testindex2/element' -d '{
"element_id": 4682,
"parent_id": null,
"wall_id": null,
"username": "John Doe",
"avatar": "56f1bb0a96d02b90e5915ff38ea189ec.jpg",
"title": "Easy Chart is a great easy comparison chart maker for math and...",
"description": "<p>Easy Chart is a great easy comparison chart maker for math and science skills. It even allows you to pick the appropriate chart type.</p>",
"groups": [
{
"id": 6,
"name": "Fourth Grade (All Subjects)",
"name_short": "4th Grade"
},
{
"id": 17,
"name": "Eighth Grade Science",
"name_short": "8th Science"
},
{
"id": 13,
"name": "Seventh Grade Science",
"name_short": "7th Science"
},
{
"id": 9,
"name": "Sixth Grade Science",
"name_short": "6th Science"
}
],
"tags": [
{
"id": 33,
"tag": "iPad"
},
{
"id": 32,
"tag": "iPod"
}
],
"webpages": [],
"videos": [],
"documents": [],
"photos": [],
"reports": [],
"bookmarks": [],
"likes": [],
"dislikes": [],
"element_type": "Post",
"active": true,
"deleted": false,
"updated_at": "2011-11-27T21:37:38-0600",
"created_at": 1322451458000,
"created_at_formatted": "2 weeks ago"
}'
Search:
$ curl -XPOST 'http://localhost:9200/testindex2/element/_search' -d '{
"sort":{ "created_at":{ "order":"desc" } },
"query":{
"constant_score":{
"filter":{
"and":[
{ "missing":{ "field":"parent_id" } },
{ "missing":{ "field":"wall_id" } },
{ "term":{ "active":true } }
]
}
}
},
"facets":{
"tags":{ "terms":{ "field":"tags.tag" }, "nested":"tags" }
}
}'
Result:
{
"took": 17,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 1,
"max_score": null,
"hits": [
{
"_index": "testindex2",
"_type": "element",
"_id": "_F1TTGJETOipo8kVR7ZXkQ",
"_score": null,
"_source": {
"element_id": 4682,
"parent_id": null,
"wall_id": null,
"username": "John Doe",
"avatar": "56f1bb0a96d02b90e5915ff38ea189ec.jpg",
"title": "Easy Chart is a great easy comparison chart maker for math and...",
"description": "<p>Easy Chart is a great easy comparison chart maker for math and science skills. It even allows you to pick the appropriate chart type.</p>",
"groups": [
{
"id": 6,
"name": "Fourth Grade (All Subjects)",
"name_short": "4th Grade"
},
{
"id": 17,
"name": "Eighth Grade Science",
"name_short": "8th Science"
},
{
"id": 13,
"name": "Seventh Grade Science",
"name_short": "7th Science"
},
{
"id": 9,
"name": "Sixth Grade Science",
"name_short": "6th Science"
}
],
"tags": [
{
"id": 33,
"tag": "iPad"
},
{
"id": 32,
"tag": "iPod"
}
],
"webpages": [],
"videos": [],
"documents": [],
"photos": [],
"reports": [],
"bookmarks": [],
"likes": [],
"dislikes": [],
"element_type": "Post",
"active": true,
"deleted": false,
"updated_at": "2011-11-27T21:37:38-0600",
"created_at": 1322451458000,
"created_at_formatted": "2 weeks ago"
},
"sort": [
1322451458000
]
}
]
},
"facets": {
"tags": {
"_type": "terms",
"missing": 0,
"total": 2,
"other": 0,
"terms": [
{
"term": "ipod",
"count": 1
},
{
"term": "ipad",
"count": 1
}
]
}
}
}
来源：https://stackoverflow.com/questions/8507489/i-cant-seem-to-get-faceted-search-working-in-elastic-search