1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
|
.. -*- rst -*-
.. highlightlang:: none
.. groonga-command
.. database: functions_highlight_html
``highlight_html``
==================
.. versionadded:: 4.0.5
Summary
-------
``highlight_html`` tags target text. It can use to highlight the search
keywords. The tagged text are prepared for embedding HTML. Special
characters such as ``<`` and ``>`` are escapsed as ``<`` and ``>``.
Keyword is surrounded with ``<span class="keyword">`` and ``</span>``.
For example, a tagged text of ``I am a groonga user. <3`` for keyword
``groonga`` is ``I am a <span class="keyword">groonga</span> user. <3``.
Syntax
------
This function has only one parameter::
highlight_html(text)
Usage
-----
Here are a schema definition and sample data to show usage.
.. groonga-command
.. include:: ../../example/reference/functions/highlight_html/usage_setup.log
.. table_create Entries TABLE_NO_KEY
.. column_create Entries body COLUMN_SCALAR ShortText
.. table_create Terms TABLE_PAT_KEY ShortText --default_tokenizer TokenBigram --normalizer NormalizerAuto
.. column_create Terms document_index COLUMN_INDEX|WITH_POSITION Entries body
.. load --table Entries
.. [
.. {"body": "Mroonga is a ＭｙＳＱＬ storage engine based on Groonga. <b>Rroonga</b> is a Ruby binding of Groonga."}
.. ]
``highlight_html`` can be used in only ``--output_columns`` in
:doc:`/reference/commands/select`.
``highlight_html`` requires :doc:`/reference/command/command_version` 2
or later.
You also need to specify ``--query`` and/or ``--filter``. Keywords are
extracted from ``--query`` and ``--filter`` arguments.
The following example uses ``--query "groonga mysql"``. In this case,
``groonga`` and ``mysql`` are used as keywords.
.. groonga-command
.. include:: ../../example/reference/functions/highlight_html/usage_basic.log
.. select Entries --output_columns --match_columns body --query 'groonga mysql' --output_columns 'highlight_html(body)' --command_version 2
The text are scanned by the keywords for tagging after they are normalized
by ``NormalizerAuto`` normalizer.
``--query "groonga mysql"`` matches to only the first record's body.
``highlight_html(body)`` surrounds the keywords ``groonga`` or ``mysql``
contained in the text with ``<span class="keyword">`` and ``</span>``.
You can specify string literal instead of column.
.. groonga-command
.. include:: ../../example/reference/functions/highlight_html/usage_string_literal.log
.. select Entries --output_columns 'highlight_html("Groonga is very fast fulltext search engine.")' --command_version 2 --match_columns body --query "groonga"
Parameters
----------
This section describes all parameters.
Required parameters
^^^^^^^^^^^^^^^^^^^
There is only one required parameters.
``text``
""""""""
The text to be highlighted in HTML.
Optional parameters
^^^^^^^^^^^^^^^^^^^
There is no optional parameter.
Return value
------------
``highlight_html`` returns a tagged string or ``null``. If
``highlight_html`` can't find any keywords, it returns ``null``.
See also
--------
* :doc:`/reference/commands/select`
* :doc:`/reference/functions/highlight_full`
|
