107 lines
5.0 KiB
Markdown
107 lines
5.0 KiB
Markdown
Mapper Attachments Type for ElasticSearch
|
|
==================================
|
|
|
|
The mapper attachments plugin adds the `attachment` type to ElasticSearch using Tika.
|
|
|
|
In order to install the plugin, simply run: `bin/plugin -install elasticsearch/elasticsearch-mapper-attachments/1.6.0`.
|
|
|
|
------------------------------------------------------
|
|
| Attachment Mapper Plugin | ElasticSearch | Tika |
|
|
------------------------------------------------------
|
|
| master | 0.21 -> master | 1.2 |
|
|
------------------------------------------------------
|
|
| 1.6.0 | 0.19 -> 0.20 | 1.2 |
|
|
------------------------------------------------------
|
|
| 1.5.0 | 0.19 -> 0.20 | 1.2 |
|
|
------------------------------------------------------
|
|
| 1.4.0 | 0.19 -> 0.20 | 1.1 |
|
|
------------------------------------------------------
|
|
| 1.3.0 | 0.19 -> 0.20 | 1.0 |
|
|
------------------------------------------------------
|
|
| 1.2.0 | 0.19 -> 0.20 | 1.0 |
|
|
------------------------------------------------------
|
|
| 1.1.0 | 0.19 -> 0.20 | |
|
|
------------------------------------------------------
|
|
| 1.0.0 | 0.18 | |
|
|
------------------------------------------------------
|
|
|
|
|
|
The `attachment` type allows to index different "attachment" type field (encoded as `base64`), for example, microsoft office formats, open document formats, ePub, HTML, and so on (full list can be found [here](http://lucene.apache.org/tika/0.10/formats.html)).
|
|
|
|
The `attachment` type is provided as a plugin extension. The plugin is a simple zip file that can be downloaded and placed under `$ES_HOME/plugins` location. It will be automatically detected and the `attachment` type will be added.
|
|
|
|
Using the attachment type is simple, in your mapping JSON, simply set a certain JSON element as attachment, for example:
|
|
|
|
{
|
|
"person" : {
|
|
"properties" : {
|
|
"my_attachment" : { "type" : "attachment" }
|
|
}
|
|
}
|
|
}
|
|
|
|
In this case, the JSON to index can be:
|
|
|
|
{
|
|
"my_attachment" : "... base64 encoded attachment ..."
|
|
}
|
|
|
|
Or it is possible to use more elaborated JSON if content type or resource name need to be set explicitly:
|
|
|
|
{
|
|
"my_attachment" : {
|
|
"_content_type" : "application/pdf",
|
|
"_name" : "resource/name/of/my.pdf",
|
|
"content" : "... base64 encoded attachment ..."
|
|
}
|
|
}
|
|
|
|
The `attachment` type not only indexes the content of the doc, but also automatically adds meta data on the attachment as well (when available). The metadata supported are: `date`, `title`, `author`, and `keywords`. They can be queried using the "dot notation", for example: `my_attachment.author`.
|
|
|
|
Both the meta data and the actual content are simple core type mappers (string, date, ...), thus, they can be controlled in the mappings. For example:
|
|
|
|
{
|
|
"person" : {
|
|
"properties" : {
|
|
"file" : {
|
|
"type" : "attachment",
|
|
"fields" : {
|
|
"file" : {"index" : "no"},
|
|
"date" : {"store" : "yes"},
|
|
"author" : {"analyzer" : "myAnalyzer"}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
In the above example, the actual content indexed is mapped under `fields` name `file`, and we decide not to index it, so it will only be available in the `_all` field. The other fields map to their respective metadata names, but there is no need to specify the `type` (like `string` or `date`) since it is already known.
|
|
|
|
Indexed Characters
|
|
------------------
|
|
|
|
By default, `100000` characters are extracted when indexing the content. This default value can be changed by setting the `index.mapping.attachment.indexed_chars` setting. It can also be provided on a per document indexed using the `_indexed_chars` parameter. `-1` can be set to extract all text, but note that all the text needs to be allowed to be represented in memory.
|
|
|
|
Note, this feature is support since `1.3.0` version.
|
|
|
|
The plugin uses [Apache Tika](http://lucene.apache.org/tika/) to parse attachments, so many formats are supported, listed [here](http://lucene.apache.org/tika/0.10/formats.html).
|
|
|
|
License
|
|
-------
|
|
|
|
This software is licensed under the Apache 2 license, quoted below.
|
|
|
|
Copyright 2009-2012 Shay Banon and ElasticSearch <http://www.elasticsearch.org>
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License"); you may not
|
|
use this file except in compliance with the License. You may obtain a copy of
|
|
the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|
WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
License for the specific language governing permissions and limitations under
|
|
the License.
|