Custom analyzer appearing in type mapping but not working in Elasticsearch - json

Question

I'm trying to add a custom analyzer to my index while also mapping that analyzer to a property on a type. Here is my JSON object for doing this:
{ "settings" : {
"analysis" : {
"analyzer" : {
"test_analyzer" : {
"type" : "custom",
"tokenizer": "standard",
"filter" : ["lowercase", "asciifolding"],
"char_filter": ["html_strip"]
}
}
}
},
"mappings" : {
"test" : {
"properties" : {
"checkanalyzer" : {
"type" : "string",
"analyzer" : "test_analyzer"
}
}
}
}
}
I know this analyzer works because I've tested it using /wp2/_analyze?analyzer=test_analyzer -d '<p>Testing analyzer.</p>' and also it shows up as the analyzer for the checkanalyzer property when I check /wp2/test/_mapping. However, if I add a document like {"checkanalyzer": "<p>The tags should not show up</p>"}, the HTML tags don't get stripped out when I retrieve the document using the _search endpoint. Am I misunderstanding how the mapping works or is there something wrong with my JSON object? I'm dynamically creating the wp2 index and also the test type when I make this call to Elasticsearch, not sure if that matters.

Answer 1

The html doesn't get removed from the source, it gets removed from the terms generated by that source. You can see this if you use a terms aggregation:
POST /test_index/_search
{
"aggs": {
"checkanalyzer_field_terms": {
"terms": {
"field": "checkanalyzer"
}
}
}
}
{
"took": 77,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 1,
"max_score": 1,
"hits": [
{
"_index": "test_index",
"_type": "test",
"_id": "1",
"_score": 1,
"_source": {
"checkanalyzer": "<p>The tags should not show up</p>"
}
}
]
},
"aggregations": {
"checkanalyzer_field_terms": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": "not",
"doc_count": 1
},
{
"key": "should",
"doc_count": 1
},
{
"key": "show",
"doc_count": 1
},
{
"key": "tags",
"doc_count": 1
},
{
"key": "the",
"doc_count": 1
},
{
"key": "up",
"doc_count": 1
}
]
}
}
}
Here's some code I used to test it:
http://sense.qbox.io/gist/2971767aa0f5949510fa0669dad6729bbcdf8570

Answer 2

Now if you want to completely strip out the html prior to indexing and storing the content as is, you can use the mapper attachment plugin - in which when you define the mapping, you can categorize the content_type to be "html."
The mapper attachment is useful for many things especially if you are handling multiple document types, but most notably - I believe just using this for the purpose of stripping out the html tags is sufficient enough (which you cannot do with the html_strip char filter).
Just a forewarning though - NONE of the html tags will be stored. So if you do need those tags somehow, I would suggest defining another field to store the original content. Another note: You cannot specify multifields for mapper attachment documents, so you would need to store that outside of the mapper attachment document. See my working example below.
You'll need to result in this mapping:
{
"html5-es" : {
"aliases" : { },
"mappings" : {
"document" : {
"properties" : {
"delete" : {
"type" : "boolean"
},
"file" : {
"type" : "attachment",
"fields" : {
"content" : {
"type" : "string",
"store" : true,
"term_vector" : "with_positions_offsets",
"analyzer" : "autocomplete"
},
"author" : {
"type" : "string",
"store" : true,
"term_vector" : "with_positions_offsets"
},
"title" : {
"type" : "string",
"store" : true,
"term_vector" : "with_positions_offsets",
"analyzer" : "autocomplete"
},
"name" : {
"type" : "string"
},
"date" : {
"type" : "date",
"format" : "strict_date_optional_time||epoch_millis"
},
"keywords" : {
"type" : "string"
},
"content_type" : {
"type" : "string"
},
"content_length" : {
"type" : "integer"
},
"language" : {
"type" : "string"
}
}
},
"hash_id" : {
"type" : "string"
},
"path" : {
"type" : "string"
},
"raw_content" : {
"type" : "string",
"store" : true,
"term_vector" : "with_positions_offsets",
"analyzer" : "raw"
},
"title" : {
"type" : "string"
}
}
}
},
"settings" : { //insert your own settings here },
"warmers" : { }
}
}
Such that in NEST, I will assemble the content as such:
Attachment attachment = new Attachment();
attachment.Content = Convert.ToBase64String(File.ReadAllBytes("path/to/document"));
attachment.ContentType = "html";
Document document = new Document();
document.File = attachment;
document.RawContent = InsertRawContentFromString(originalText);
I have tested this in Sense - results are as follows:
"file": {
"_content": "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",
"_content_length": 0,
"_content_type": "html",
"_date": "0001-01-01T00:00:00",
"_title": "Topic10"
},
"delete": false,
"raw_content": "<h1>Topic10</h1><p>Delete this text and replace it with your own content. Check your mailbox.</p><p> </p><p>asdf</p><p> </p><p>10</p><p> </p><p>Lavender.</p><p> </p><p>10/6 12:03</p><p> </p><p>5 09</p><p> </p><p>11 47</p><p> </p><p>Halloween is in October.</p><p> </p><p>jog</p>"
},
"highlight": {
"file.content": [
"\n <em>Topic10</em>\n\n Delete this text and replace it with your own content. Check your mailbox.\n\n  \n\n asdf\n\n  \n\n 10\n\n  \n\n Lavender.\n\n  \n\n 10/6 12:03\n\n  \n\n 5 09\n\n  \n\n 11 47\n\n  \n\n Halloween is in October.\n\n  \n\n jog\n\n "
]
}