Search Pattern Cookbook
The Search function is very powerful. Searches using a
RegularExpression play an important part of tapping Foswiki's full potential. Unfortunately
RegularExpressions can be incredibly obscure to the uninitiated.
Most people not familiar (enough) with Regular Expressions mostly cut and paste (and maybe tweak) from existing examples. This page intends to collect lots of examples together.
Pattern 1: Extract values from a table
Problem definition
Suppose there is a topic with a table defining entries in a
DataForm? . I.e. they define select menu items in a form definition. They are then formatted like:
| *Name* | *Type* | *Tooltip message* |
| option1 | option | |
| option2 | option | |
| option3 | option | |
How to extract the 'name' values, i.e. 'option1', 'option2' and 'option3' and put them in a HTML form select input?
Solution 1
The following search pattern can be employed:
<form>
<select>
%SEARCH{
"^\|[^\|]*\| *option *\|"
topic="%TOPIC%"
type="regex"
multiple="on"
nonoise="on"
format="<option>$pattern(^\| *(.*?) *\|.*)</option>"
}%
</select>
</form>
which is, in effect:
Solution 2
If your table has this format:
| *Country* |
| |
| Afghanistan |
| Aland Islands |
| Albania |
| Algeria |
| American Samoa |
| Andorra |
You need to skip the header row. Use this search:
<select>
%SEARCH{
"^\|[^\*\|]*\|"
topic="CountryList"
type="regex"
multiple="on"
nonoise="on"
format="<option>$pattern(^\| *(.*?) *\|.*)</option>"
}%
</select>
Which renders as:
Afghanistan
Aland Islands
Albania
Algeria
American Samoa
Andorra
Angola
Anguilla
Antarctica
Antigua and Barbuda
Argentina
Armenia
Aruba
Australia
Austria
Azerbaijan
Bahamas
Bahrain
Bangladesh
Barbados
Belarus
Belgium
Belize
Benin
Bermuda
Bhutan
Bolivia
Bosnia and Herzegovina
Botswana
Bouvet Island
Brazil
British Indian Ocean Territory
British Virgin Islands
Brunei
Bulgaria
Burkina Faso
Burundi
Cambodia
Cameroon
Canada
Cape Verde
Cayman Islands
Central African Republic
Chad
Chile
China
Christmas Island
Cocos Islands
Colombia
Comoros
Congo - Brazzaville
Congo - Kinshasa
Cook Islands
Costa Rica
Croatia
Cuba
Cyprus
Czech Republic
Denmark
Djibouti
Dominica
Dominican Republic
East Timor
Ecuador
Egypt
El Salvador
Equatorial Guinea
Eritrea
Estonia
Ethiopia
Falkland Islands
Faroe Islands
Fiji
Finland
France
French Guiana
French Polynesia
French Southern Territories
Gabon
Gambia
Georgia
Germany
Ghana
Gibraltar
Greece
Greenland
Grenada
Guadeloupe
Guam
Guatemala
Guernsey
Guinea
Guinea-Bissau
Guyana
Haiti
Heard Island and McDonald? Islands
Honduras
Hong Kong
Hungary
Iceland
India
Indonesia
Iran
Iraq
Ireland
Isle of Man
Israel
Italy
Ivory Coast
Jamaica
Japan
Jersey
Jordan
Kazakhstan
Kenya
Kiribati
Kuwait
Kyrgyzstan
Laos
Latvia
Lebanon
Lesotho
Liberia
Libya
Liechtenstein
Lithuania
Luxembourg
Macao
Macedonia
Madagascar
Malawi
Malaysia
Maldives
Mali
Malta
Marshall Islands
Martinique
Mauritania
Mauritius
Mayotte
Mexico
Micronesia
Moldova
Monaco
Mongolia
Montenegro
Montserrat
Morocco
Mozambique
Myanmar
Namibia
Nauru
Nepal
Netherlands
Netherlands Antilles
New Caledonia
New Zealand
Nicaragua
Niger
Nigeria
Niue
Norfolk Island
North Korea
Northern Mariana Islands
Norway
Oman
Pakistan
Palau
Palestinian Territory
Panama
Papua New Guinea
Paraguay
Peru
Philippines
Pitcairn
Poland
Portugal
Puerto Rico
Qatar
Reunion
Romania
Russia
Rwanda
Saint Barthélemy
Saint Helena
Saint Kitts and Nevis
Saint Lucia
Saint Martin
Saint Pierre and Miquelon
Saint Vincent and the Grenadines
Samoa
San Marino
Sao Tome and Principe
Saudi Arabia
Senegal
Serbia
Seychelles
Singapore
Slovakia
Slovenia
Solomon Islands
Somalia
South Africa
South Georgia and the South Sandwich Islands
South Korea
Spain
Sri Lanka
Sudan
Suriname
Svalbard and Jan Mayen
Swaziland
Sweden
Switzerland
Syria
Taiwan
Tajikistan
Tanzania
Thailand
Togo
Tokelau
Tonga
Trinidad and Tobago
Tunisia
Turkey
Turkmenistan
Turks and Caicos Islands
Tuvalu
U.S. Virgin Islands
Uganda
Ukraine
United Arab Emirates
United Kingdom
United States
United States Minor Outlying Islands
Uruguay
Uzbekistan
Vanuatu
Vatican
Venezuela
Vietnam
Wallis and Futuna
Western Sahara
Yemen
Zambia
Zimbabwe
Pattern 2: List generated from form classification
Problem
Imagine a form-based topic classification, i.e. every page has a form with several fields. How to:
create a search to display all topics where one form field is set to a certain value
create a search to filter the list above based on the values of a second form field
Test case
In practice:
Image a form with two fields:
TopicClassification = One, Two or Three
TopicStatus = Test or Final
We will:
List all topics where the TopicClassification field is set to 'Two'
Enable the user to filter this list based on the values of TopicStatus
Solution
%SEARCH{
"TopicClassification='%URLPARAM{type}%'"
type="query"
nonoise="on"
sort="topic"
format=" * $topic - <font face='arial,helvetica' size='1'>
_last modified by_ $wikiusername _on_ $date </font> %BR%
<font face='arial,helvetica' size='1'> $formfield(TopicStatus) </font>"
}%
The filtering select dialogue is created as in Pattern 1:
%STARTSIDEBAR%
*Filter:* %BR%
<form name="selectType" action="%SCRIPTURLPATH{"view"}%/%WEB%/" >
<select name="type" size="1" onchange="document.location=this.value;">
%SEARCH{
"^\|[^\|]*\| *option *\|"
topic="TopicClassification"
type="regex"
nonoise="on"
format="<option value='%BASETOPIC%?type=$pattern(^\| *(.*?) *\|.*)'>
$pattern(^\| *(.*?) *\|.*)</option>"
}%
<option value='%BASETOPIC%'>All pages</option>
</select>
</form>
%STOPSIDEBAR%
This will create similar functionality as
Foswiki:Extensions.TopicClassificationAddOn
Pattern 3: Extract the parent of a given topic
Problem
How to get to the parent of the current topic to display on the page?
Solution 1: Using QUERY
Use the QUERY macro:
%QUERY{ "parent.name" }%
Test case
FormattedSearch
Pattern 4: Show all Children of a given topic
Problem
How to get to the list of all children of the current topic to display on the page?
Solution
The parent information is stored in the topic meta data. Do a SEARCH to find all topic parent meta data pointing to the current topic:
Children:
%SEARCH{
"parent.name='%TOPIC%'"
type="query"
nonoise="on"
format="[[$topic]]"
separator=", "
}%
Note: Replace
%TOPIC%
with
%BASETOPIC%
if you put this SEARCH into the skin or a sidebar.
See also
HierarchicalNavigation for an elaborate example.
Pattern 5: Search and display the home topics of public webs in a list
Problem
How to find and display public webs in a drop down list box.
Solution
<form>
<select name="topic">
<option value="%TOPIC%">Select...</option>
%SEARCH{
"%HOMETOPIC%"
scope="topic"
web="all"
topic="%HOMETOPIC%"
format="<option value='$web.$topic'>$web</option>"
separator=" "
}%
</select>
<input type="submit" class="foswikiSubmit" value="Go" />
</form>
Test case
Public webs can be found with the %WEBLIST% macro.
Pattern 6: Create a select box with values from a bullet list
Problem
We have a topic with a bullet list with category names. In another topic we want to offer these values in a select box dropdown.
For example, CategoryList has:
Clients
People
Rooms
Buildings
Solution
The following search pattern can be employed:
<select name="type">
<option>Select category...</option>
%SEARCH{
" *\s*.*?"
topic="CategoryList"
type="regex"
multiple="on"
casesensitive="on"
nonoise="on"
format="<option>$pattern(.* \*\s*([^\n]*).*)</option>"
}%
</select>
To render the bullet list as a comma-separated list, use the
separator
parameter:
%SEARCH{
" *\s*.*?"
topic="CategoryList"
type="regex"
multiple="on"
casesensitive="on"
nonoise="on"
separator=","
format="$pattern(.* \*\s*([^\n]*).*)"
}%
Pattern 7: Search all topics that have been moved
Problem
How would I go about listing all moved topics ?
Solution
Search for the 'moved' meta data. Type this:
Moved topics: %SEARCH{
"moved.from=~'\w+'"
web="all"
type="query"
separator=", "
format="$web.$topic"
nonoise="on"
}%
Test case
Moved topics:
CompleteDocumentation ,
TaggedTopicRenderIndexItem ,
AjaxWebSelector ,
AppendixCascadingStyleSheets ,
Creating applications with DataForms ,
Deleting and renaming topics ,
Deleting and renaming attachments ,
Get Foswiki ,
Explanation of Foswiki's =repRev= feature , System.FAQForm,
Foswiki software license ,
Fixing broken =%SEARCH= caused by faulty configuration. ,
How simultaneous edits are handled in Foswiki ,
Definition of "WikiWiki" ,
NatSkinConfiguration ,
VarMETASEARCH
Pattern 8: Extract level-1 headings
How do I go about extracting the first occurance of a level-1 heading?
Solution
Use the
$pattern()
token. Type this:
%SEARCH{
"^---[+][^+][^\r\n]+[\r\n]"
type="regex"
nonoise="on"
header="Headings:"
limit="5"
format=" * [[$topic][$pattern([\r\n\-+!]+([^\r\n]*?)[\r\n].*)]]"
footer="Found $ntopics topics with level-1 headings"
}%
Test case
Headings:
Found 5 topics with level-1 headings
Related Topics: UserDocumentationCategory ,
SearchHelp ,
Macros ,
FormattedSearch ,
RegularExpression