Configuration file format -- Attributes

ht://Dig Copyright © 1995-1999 The ht://Dig Group
Please see the file COPYING for license information.

Alphabetical list of attributes

add_anchors_to_excerpt
type:
boolean
used by:
htsearch
default:
true
description:
If set to true, the first occurrence of each matched word in the excerpt will be linked to the closest anchor in the document. This only has effect if the EXCERPT variable is used in the output template and the excerpt is actually going to be displayed.
example:
add_anchors_to_excerpt: no
allow_in_form
type:
string list
used by:
htsearch
default:
<empty>
description:
Allows the specified config file attributes to be specified in search forms as separate fields. This could be used to allow form writers to design their own headers and footers and specify them in the search form. Another example would be to offer a menu of search_algorithms in the form.
  <SELECT NAME="search_algorithm">
  <OPTION VALUE="exact:1 prefix:0.6 synonyms:0.5 endings:0.1" SELECTED>fuzzy
  <OPTION VALUE="exact:1">exact
  </SELECT>
example:
allow_in_form: search_algorithm search_results_header
allow_numbers
type:
boolean
used by:
htdig
default:
false
description:
If set to true, numbers are considered words. This means that searches can be done on number as well as regular words. All the same rules apply to numbers as to words. See the description of valid_punctuation for the rules used to determine what a word is.
example:
allow_numbers: true
allow_virtual_hosts
type:
boolean
used by:
htdig
default:
true
description:
If set to true, htdig will index virtual web sites as expected. If false, all URL host names will be normalized into whatever the DNS server claims the IP address to map to. If this option is set to false, there is no way to index either "soft" or "hard" virtual web sites.
example:
allow_virtual_hosts: false
backlink_factor
type:
number
used by:
htsearch
default:
1000
description:
This is a weight of "how important" a page is, based on the number of URLs pointing to it. It's actually multiplied by the ratio of the incoming URLs (backlinks) and outgoing URLs, to balance out pages with lots of links to pages that link back to them. This factor can be changed without changing the database in any way. However, setting this value to something other than 0 incurs a slowdown on search results.
example:
backlink_factor: 501.1
bad_extensions
type:
string list
used by:
htdig
default:
.wav .gz .z .sit .au .zip .tar .hqx .exe .com .gif .jpg .jpeg .aiff .class .map .ram .tgz .bin .rpm .mpg .mov .avi
description:
This is a list of extensions on URLs which are considered non-parsable. This list is used mainly to supplement the MIME-types that the HTTP server provides with documents. Some HTTP servers do not have a correct list of MIME-types and so can advertise certain documents as text while they are some binary format.
example:
bad_extensions: .foo .bar .bad
bad_querystr
type:
string list
used by:
htdig
default:
<empty>
description:
This is a list of CGI query strings to be excluded from indexing. This can be used in conjunction with CGI-generated portions of a website to control which pages are indexed.
example:
bad_querystr: forum=private section=topsecret&passwd=required
bad_word_list
type:
string
used by:
htdig and htsearch
default:
${common_dir}/bad_words
descriptions:
This specifies a file which contains words which should be excluded when digging or searching. This list should include the most common words or other words that you don't want to be able to search on (things like sex or smut are examples of these.)
The file should contain one word per line. A sample bad words file is located in the contrib/examples directory.
example:
bad_word_list: ${common_dir}/badwords.txt
bin_dir
type:
string
used by:
htdig, htnotify, htfuzzy, htmerge and htsearch
default:
BIN_DIR
description:
This is the directory in which the executables related to ht://Dig are installed. It is never used directly by any of the programs, but other attributes can be defined in terms of this one.

The default value of this attribute is determined at compile time.

example:
bin_dir: /usr/local/bin
case_sensitive
type:
boolean
used by:
htdig
default:
true
description:
This specifies whether ht://Dig should consider URLs case-sensitive or not. If your server is case-insensitive, you should probably set this to false.
example:
case_sensitive: false
common_dir
type:
string
used by:
htdig, htnotify, htfuzzy, htmerge and htsearch
default:
COMMON_DIR
description:
Specifies the directory for files that will or can be shared among different search databases. The default value for this attribute is defined at compile time.
example:
common_dir: /tmp
common_url_parts
type:
string list
used by:
htdig, htnotify, htmerge and htsearch
default:
http:// http://www. ftp:// ftp://ftp. /pub/ .html .gif .jpg .jpeg /index.html /index.htm .com/ .com mailto:
description:
Sub-strings often found in URLs stored in the database. These are replaced in the database by an internal space-saving encoding. If a string specified in url_part_aliases, overlaps any string in common_url_parts, the common_url_parts string is ignored.
Note that when this attribute is changed, the database should be rebuilt, unless the effect of "changing" the affected URLs in the database is wanted.
example:
common_url_parts: http://www.htdig.org/ml/ \
.html \
http://dev.htdig.org/ \
http://www.htdig.org/
compression_level
type:
number
used by:
htdig
default:
0
description:
If specified and the zlib compression library was available when compiled, this attribute controls the amount of compression used in the doc_db file. Defaults to zero to provide backward compatility with old databases.
example:
compression_level: 6
config_dir
type:
string
used by:
htdig, htnotify, htfuzzy, htmerge and htsearch
default:
CONFIG_DIR
description:
This is the directory which contains all configuration files related to ht://Dig. It is never used directly by any of the programs, but other attributes or the include directive can be defined in terms of this one.

The default value of this attribute is determined at compile time.

example:
config_dir: /var/htdig/conf
create_image_list
type:
boolean
used by:
htdig
default:
false
description:
If set to true, a file with all the image URLs that were seen will be created, one URL per line. This list will not be in any order and there will be lots of duplicates, so after htdig has completed, it should be piped through sort -u to get a unique list.
example:
create_image_list: yes
create_url_list
type:
boolean
used by:
htdig
default:
false
description:
If set to true, a file with all the URLs that were seen will be created, one URL per line. This list will not be in any order and there will be lots of duplicates, so after htdig has completed, it should be piped through sort -u to get a unique list.
example:
create_url_list: yes
database_base
type:
string
used by:
htdig, htnotify, htfuzzy, htmerge and htsearch
default:
${database_dir}/db
description:
This is the common prefix for files that are specific to a search database. Many different attributes use this prefix to specify filenames. Several search databases can share the same directory by just changing this value for each of the databases.
example:
database_base: ${database_dir}/sales
database_dir
type:
string
used by:
htdig, htnotify, htfuzzy, htmerge and htsearch
default:
DATABASE_DIR
description:
This is the directory which contains all database and other files related to ht://Dig. It is never used directly by any of the programs, but other attributes are defined in terms of this one.

The default value of this attribute is determined at compile time.

example:
database_dir: /var/htdig
date_factor
type:
number
used by:
htsearch
default:
0
description:
This factor, like backlink_factor can be changed without modifing the database. It gives higher rankings to newer documents and lower rankings to older documents. Before setting this factor, it's advised to make sure your servers are returning accurate dates (check the dates returned in the long format). Additionally, setting this to a nonzero value incurs a performance hit on searching.
example:
date_factor: 0.35
date_format
type:
string
used by:
htsearch
default:
<empty>
description:
This format string determines the output format for modification dates of documents in the search results. It is interpreted by your system's strftime function. Please refer to your system's manual page for this function, for a description of available format codes. If this format string is empty, as it is by default, htsearch will pick a format itself. In this case, the iso_8601 attribute can be used to modify the appearance of the date.
example:
date_format: %Y-%m-%d
description_factor
type:
number
used by:
htdig
default:
150
description:
Plain old "descriptions" are the text of a link pointing to a document. This factor gives weight to the words of these descriptions of the document. Not surprisingly, these can be pretty accurate summaries of a document's content. See also title_factor or text_factor. Changing this factor will require updating your database.
example:
description_factor: 350
doc_db
type:
string
used by:
htdig, htmerge and htsearch,
default:
${database_base}.docdb
description:
This file will contain a Berkeley database of documents indexed by URL. It contains all the information gathered for each document, so this file can become rather large if max_head_length is set to a large value.
example:
doc_db: ${database_base}documents.db
doc_index
type:
string
used by:
htmerge and htsearch,
default:
${database_base}.docs.index
description:
This file will contain a Berkeley database which maps document numbers to document URLs. It is basically an intermediate database from the word database to the document database.
example:
doc_index: documents.index.db
doc_list
type:
string
used by:
htdig
default:
${database_base}.docs
description:
This file is basically a text version of the file specified in doc_db. Its only use is to have a human readable database of all documents. The file is easy to parse with tools like perl or tcl.
example:
doc_list: /tmp/documents.text
end_ellipses
type:
string
used by:
htsearch
default:
<b><tt> ...</tt></b>
description:
When excerpts are displayed in the search output, this string will be appended to the excerpt if there is text following the text displayed. This is just a visual reminder to the user that the excerpt is only part of the complete document.
example:
end_ellipses: ...
endings_affix_file
type:
string
used by:
htfuzzy
default:
${common_dir}/english.aff
description:
Specifies the location of the file which contains the affix rules used to create the endings search algorithm databases. Consult the documentation on htfuzzy for more information on the format of this file.
example:
endings_affix_file: /var/htdig/affix_rules
endings_dictionary
type:
string
used by:
htfuzzy
default:
${common_dir}/english.0
description:
Specifies the location of the file which contains the dictionary used to create the endings search algorithm databases. Consult the documentation on htfuzzy for more information on the format of this file.
example:
endings_dictionary: /var/htdig/dictionary
endings_root2word_db
type:
string
used by:
htfuzzy and htsearch
default:
${common_dir}/root2word.db
description:
This attributes specifies the database filename to be used in the 'endings' fuzzy search algorithm. The database maps word roots to all legal words with that root. For more information about this and other fuzzy search algorithms, consult the htfuzzy documentation.
Note that the default value uses the common_dir attribute instead of the database_dir attribute. This is because this database can be shared with different search databases.
example:
endings_root2word_db: /var/htdig/r2w.db
endings_word2root_db
type:
string
used by:
htfuzzy and htsearch
default:
${common_dir}/word2root.db
description:
This attributes specifies the database filename to be used in the 'endings' fuzzy search algorithm. The database maps words to their root. For more information about this and other fuzzy search algorithms, consult the htfuzzy documentation.
Note that the default value uses the common_dir attribute instead of the database_dir attribute. This is because this database can be shared with different search databases.
example:
endings_word2root_db: /var/htdig/w2r.bm
excerpt_length
type:
number
used by:
htsearch
default:
300
description:
This is the maximum number of characters the displayed excerpt will be limited to. The first matched word will be bolded in the middle of the excerpt so that there is some surrounding context.
The start_ellipses and end_ellipses are used to indicate that the document contains text before and after the displayed excerpt respectively.
example:
excerpt_length: 500
excerpt_show_top
type:
boolean
used by:
htsearch
default:
false
description:
If set to true, the excerpt of a match will always show the top of the matching document. If it is false (the default), the excerpt will attempt to show the part of the document that actually contains one of the words.
example:
excerpt_show_top: yes
exclude_urls
type:
string list
used by:
htdig
default:
/cgi-bin/ .cgi
description:
If a URL contains any of the space separated patterns, it will be rejected. This is used to exclude such common things such as an infinite virtual web-tree which start with cgi-bin.
example:
exclude_urls: students.html cgi-bin
external_parsers
type:
quoted string list
used by:
htdig
default:
<empty>
description:
This attribute is used to specify a list of content-type/parsers that are to be used to parse documents that cannot by parsed by any of the internal parsers. The list of external parsers is examined before the builtin parsers are checked, so this can be used to override the internal behavior without recompiling htdig.
The external parsers are specified as pairs of strings. The first string of each pair is the content-type that the parser can handle while the second string of each pair is the path to the external parsing program. If quoted, it may contain parameters, separated by spaces.

The parser program takes four command-line parameters, not counting parameters and parameters given in the command string:
infile content-type URL configuration-file
Parameter Description Example
infile A temporary file with the contents to be parsed. /var/tmp/htdext.14242
content-type The MIME-type of the contents. text/html
URL The URL of the contents. http://www.htdig.org/attrs.html
configuration-file The configuration-file in effect. /etc/htdig/htdig.conf

The external parser is to write information for htdig on its standard output.
The output consists of records, each record terminated with a newline. Each record is a series of (unless expressively allowed to be empty) non-empty tab-separated fields. The first field is a single character that specifies the record type. The rest of the fields are determined by the record type.
Record type Fields Description
w word A word that was found in the document.
location A number indicating the normalized location of the word within the document. The number has to fall in the range 0-1000 where 0 means the top of the document.
heading level A heading level that is used to compute the weight of the word depending on its context in the document itself. The level is in the range of 0-10 and are defined as follows:
0
Normal text
1
Title text
2
Heading 1 text
3
Heading 2 text
4
Heading 3 text
5
Heading 4 text
6
Heading 5 text
7
Heading 6 text
8
unused
9
unused
10
Keywords
u document URL A hyperlink to another document that is referenced by the current document. It must be complete and non-relative, using the URL parameter to resolve any relative references found in the document.
hyperlink description For HTML documents, this would be the text between the <a href...> and </a> tags.
t title The title of the document
h head The top of the document itself. This is used to build the excerpt. This should only contain normal ASCII text
a anchor The label that identifies an anchor that can be used as a target in an URL. This really only makes sense for HTML documents.
i image URL An URL that points at an image that is part of the document.
m http-equiv The HTTP-EQUIV attribute of a META tag. May be empty.
name The NAME attribute of this META tag. May be empty.
contents The CONTENTS attribute of this META tag. May be empty.

example:
external_parsers: text/html /usr/local/bin/htmlparser \
application/ms-word "/usr/local/bin/mswordparser -w"
extra_word_characters
type:
string
used by:
htdig and htsearch
default:
<empty>
description:
These characters are considered part of a word. In contrast to the characters in the valid_punctuation attribute, they are treated just like letter characters.
Note that the locale attribute is normally used to configure which characters constitute letter characters.
example:
extra_word_characters: _
heading_factor_1 - heading_factor_6
type:
number
used by:
htdig
default:
heading_factor_1: 5
heading_factor_2: 4
heading_factor_3: 3
heading_factor_4: 1
heading_factor_5: 1
heading_factor_6: 0
description:
This is a factor which will be used to multiply the weight of words between <h1> and </h1> tags. It is used to assign the level of importance to certain headers. Setting a factor to 0 will cause words in this heading to be ignored. The number may be a floating point number. See also the title_factor and text_factor attributes.
example:
heading_factor_1: 7.75
heading_factor_2: 5.3
heading_factor_3: 2
heading_factor_4: 0
heading_factor_5: 0
heading_factor_6: 0
htnotify_sender
type:
string
used by:
htnotify
default:
webmaster@www
description:
This specifies the email address that htnotify email messages get sent out from. The address is forged using /usr/lib/sendmail. Check htnotify/htnotify.cc for detail on how this is done.
example:
htnotify_sender: bigboss@yourcompany.com
http_proxy
type:
string
used by:
htdig
default:
<empty>
description:
When this attribute is set, all HTTP document retrievals will be done using the HTTP-PROXY protocol. The URL specified in this attribute points to the host and port where the proxy server resides.
The use of a proxy server greatly improves performance of the indexing process.
example:
http_proxy: http://proxy.bigbucks.com:3128
http_proxy_exclude
type:
string list
used by:
htdig
default:
<empty>
description:
When this is set, URLs matching this will not use the proxy. This is useful when you have a mixture of sites near to the digging server and far away.
example:
http_proxy_exclude: http://intranet.foo.com/
image_list
type:
string
used by:
htdig
default:
${database_base}.images
description:
This is the file that a list of image URLs gets written to by htdig when the create_image_list is set to true. As image URLs are seen, they are just appended to this file, so after htdig finishes it is probably a good idea to run sort -u on the file to eliminate duplicates from the file.
example:
image_list: allimages
image_url_prefix
type:
string
used by:
htsearch
default:
IMAGE_URL_PREFIX
description:
This specifies the directory portion of the URL used to display star images. This attribute isn't directly used by htsearch, but is used in the default URL for the star_image and star_blank attributes, and other attributes may be defined in terms of this one.

The default value of this attribute is determined at compile time.

example:
image_url_prefix: /images/htdig
include
type:
string
used by:
htdig, htnotify, htfuzzy, htmerge and htsearch
description:
This is not quite a configuration attribute, but rather a directive. It can be used within one configuration file to include the definitions of another file. The last definition of an attribute is the one that applies, so after including a file, any of its definitions can be overridden with subsequent definitions. This can be useful when setting up many configurations that are mostly the same, so all the common attributes can be maintained in a single configuration file. The include directives can be nested, but watch out for nesting loops.
example:
include: ${config_dir}/htdig.conf
iso_8601
type:
boolean
used by:
htsearch and htnotify
default:
false
description:
This sets whether dates should be output in ISO 8601 format. For example, this was written on: 1998-10-31 11:28:13 EST. See also the date_format attribute, which can override any date format that htsearch picks by default.
This attribute also affects the format of the date htnotify expects to find in a htdig-notification-date field.
example:
iso_8601: true
keywords_factor
type:
number
used by:
htdig
default:
100
description:
This is a factor which will be used to multiply the weight of words in the list of keywords of a document. The number may be a floating point number. See also the title_factor and text_factorattributes.
example:
keywords_factor: 12
keywords_meta_tag_names
type:
string list
used by:
htdig
default:
keywords htdig-keywords
description:
The words in this list are used to search for keywords in HTML META tags. This list can contain any number of strings that each will be seen as the name for whatever keyword convention is used.
The META tags have the following format:
  <META name="somename" content="somevalue">
example:
keywords_meta_tag_names: keywords description
limit_normalized
type:
string list
used by:
htdig
default:
<empty>
description:
This specifies a set of patterns that all URLs have to match against in order for them to be included in the search. Unlike the limit_urls_to directive, this is done after the URL is normalized and the server_aliases directive is applied. This allows filtering after any hostnames and DNS aliases are resolved. Otherwise, this directive is the same as the limit_urls_to directive.
example:
limit_normalized: http://www.mydomain.com
limit_urls_to
type:
string list
used by:
htdig
default:
${start_url}
description:
This specifies a set of patterns that all URLs have to match against in order for them to be included in the search. Any number of strings can be specified, separated by spaces. If multiple patterns are given, at least one of the patterns has to match the URL.
Matching is a case-insensitive string match on the URL to be used. The match will be performed after the relative references have been converted to a valid URL. This means that the URL will always start with http://.
Granted, this is not the perfect way of doing this, but it is simple enough and it covers most cases.
example:
limit_urls_to: .sdsu.edu kpbs
local_default_doc
type:
string
used by:
htdig
default:
index.html
description:
Set this to the default document in a directory used by the server. This is used for local filesystem access to translate URLs like http://foo.com/ into something like /home/foo.com/index.html
example:
local_default_doc: default.html
local_urls
type:
string list
used by:
htdig
default:
<empty>
description:
Set this to tell ht://Dig to access certain URLs through local filesystems. At first ht://Dig will try to access pages with URLs matching the patterns through the filesystems specified. If it cannot find the file, it will try the URL through HTTP instead. Note the example--the equal sign and the final slashes in both the URL and the directory path are critical.
example:
local_urls: http://www.foo.com/=/usr/www/htdocs/
local_user_urls
type:
string list
used by:
htdig
default:
<empty>
description:
Set this to access user directory URLs through the local filesystem. If you leave the "path" portion out, it will look up the user's home directory in /etc/password (or NIS or whatever). As with local_urls, if the files are not found, ht://Dig will try with HTTP. Again, note the example's format. To map http://www.my.org/~joe/foo/bar.html to /home/joe/www/foo/bar.html, try the example below.
example:
local_user_urls: http://www.my.org/=/home/,/www/
locale
type:
string
used by:
htdig
default:
C
description:
Set this to whatever locale you want your search database cover. It affects the way international characters are dealt with. On most systems a list of legal locales can be found in /usr/lib/locale. Also check the setlocale(3C) man page.
example:
locale: en_US
logging
type:
boolean
used by:
htsearch
default:
false
description:
This sets whether htsearch should use the syslog() to log search requests. If set, this will log requests with a default level of LOG_INFO and a facility of LOG_LOCAL5. For details on redirecting the log into a separate file or other actions, see the syslog.conf(5) man page. To set the level and facility used in logging, change LOG_LEVEL and LOG_FACILITY in the include/htconfig.h file before compiling.
example:
logging: true
maintainer
type:
string
used by:
htdig
default:
bogus@unconfigured.htdig.user
description:
This should be the email address of the person in charge of the digging operation. This string is added to the user-agent: field when the digger sends a request to a server.
example:
maintainer: ben.dover@uptight.com
match_method
type:
string
used by:
htsearch
default:
and
description:
This is the default method for matching that htsearch uses. The valid choices are:
  • or
  • and
  • boolean
This attribute will only be used if the HTML form that calls htsearch didn't have the method value set.
example:
match_method: boolean
matches_per_page
type:
number
used by:
htsearch
default:
10
description:
If this is set to a relatively small number, the matches will be shown in pages instead of all at once.
example:
matches_per_page: 999
max_description_length
type:
number
used by:
htdig
default:
60
description:
While gathering descriptions of URLs, htdig will only record those descriptions which are shorter than this length. This is used mostly to deal with broken HTML. (If a hyperlink is not terminated with a </a> the description will go on until the end of the document.)
example:
max_description_length: 40
max_doc_size
type:
number
used by:
htdig
default:
100000
description:
This is the upper limit to the amount of data retrieved for documents. This is mainly used to prevent unreasonable memory consumption since each document will be read into memory by htdig.
example:
max_doc_size: 5000000
max_head_length
type:
number
used by:
htdig
default:
512
description:
For each document retrieved, the top of the document is stored. This attribute determines the size of this block. The text that will be stored is only the text; no markup is stored.
We found that storing 50,000 bytes will store about 95% of all the documents completely. This really depends on how much storage is available and how much you want to show.
example:
max_head_length: 50000
max_hop_count
type:
number
used by:
htdig
default:
999999
description:
Instead of limiting the indexing process by URL pattern, it can also be limited by the number of hops or clicks a document is removed from the starting URL. Unfortunately, this only works reliably when a complete index is created, not an update.
The starting page will have hop count 0.
example:
max_hop_count: 4
max_meta_description_length
type:
number
used by:
htdig
default:
512
description:
While gathering descriptions from meta description tags, htdig will truncate descriptions which are longer than this length.
example:
max_meta_description_length: 1000
max_prefix_matches
type:
integer
used by:
htsearch
default:
1000
description:
The Prefix fuzzy algorithm could potentially match a very large number of words. This value limits the number of words each prefix can match. Note that this does not limit the number of documents that are matched in any way.
example:
max_prefix_matches: 100
max_stars
type:
number
used by:
htsearch
default:
4
description:
When stars are used to display the score of a match, this value determines the maximum number of stars that can be displayed.
example:
max_stars: 6
maximum_pages
type:
integer
used by:
htsearch
default:
10
description:
This value limits the number of page links that will be included in the page list at the bottom of the search results page. Note that this does not limit the number of documents that are matched in any way.
example:
maximum_pages: 20
maximum_word_length
type:
number
used by:
htdig and htsearch
default:
12
description:
This sets the maximum length of words that will be indexed. Words longer than this value will be silently truncated when put into the index, or searched in the index.
example:
maximum_word_length: 15
meta_description_factor
type:
number
used by:
htdig
default:
50
description:
This is a factor which will be used to multiply the weight of words in any META description tags in a document. The number may be a floating point number. See also the title_factor and text_factor attributes.
example:
meta_description_factor: 20
metaphone_db
type:
string
used by:
htfuzzy and htsearch
default:
${database_base}.metaphone.db
description:
The database file used for the fuzzy "metaphone" search algorithm. This database is created by htfuzzy and used by htsearch.
example:
metaphone_db: ${database_base}.mp.db
method_names
type:
quoted string list
used by:
htsearch
default:
and All or Any boolean Boolean
description:
These values are used to create the method menu. It consists of pairs. The first element of each pair is one of the known methods, the second element is the text that will be shown in the menu for that method. This text needs to be quoted if it contains spaces.
example:
method_names: or Or and And
minimum_prefix_length
type:
number
used by:
htsearch
default:
1
description:
This sets the minimum length of prefix matches used by the "prefix" fuzzy matching algorithm. Words shorter than this will not be used in prefix matching.
example:
minimum_prefix_length: 2
minimum_word_length
type:
number
used by:
htdig and htsearch
default:
3
description:
This sets the minimum length of words that will be indexed. Words shorter than this value will be silently ignored but still put into the excerpt.
Note that by making this value less than 3, a lot more words that are very frequent will be indexed. It might be advisable to add some of these to the bad_words list.
example:
minimum_word_length: 2
modification_time_is_now
type:
boolean
used by:
htdig
default:
false
description:
This sets ht://Dig's response to a server that does not return a modification date. By default, it stores nothing. By setting modification_time_is_now, it will store the current time if the server does not return a date. Though this will return incorrect dates in search results, it will cut down on reindexing from such servers when doing updates.
example:
modification_time_is_now: true
next_page_text
type:
string
used by:
htsearch
default:
[next]
description:
The text displayed in the hyperlink to go to the next page of matches.
example:
next_page_text: <img src="/htdig/buttonr.gif">
no_excerpt_show_top
type:
boolean
used by:
htsearch
default:
false
description:
If no excerpt is available, this option will act the same as excerpt_show_top, that is, it will show the top of the document.
example:
no_excerpt_show_top: yes
no_excerpt_text
type:
string
used by:
htsearch
default:
<em>(None of the search words were found in the top of this document.)</em>
description:
This text will be displayed in place of the excerpt if there is no excerpt available. If this attribute is set to nothing (blank), the excerpt label will not be displayed in this case.
example:
no_excerpt_text:
noindex_start, noindex_end
type:
string
used by:
htdig
default:
<!--htdig_noindex--> <!--/htdig_noindex-->
description:
The text encompassing a section of an HTML file that should be completely ignored when indexing. As in the defaults, this can be SGML comment declarations that can be inserted anywhere in the documents to exclude different sections from being indexed. However, existing tags can also be used; this is especially useful to exclude some sections from being indexed where the files to be indexed can not be edited. The example shows how SCRIPT sections in 'uneditable' documents can be skipped; note how noindex_start does not contain an ending >: this allows for all SCRIPT tags to be matched regardless of attributes defined (different types or languages). Note that the match for this string is case insensitive.
example:
noindex_start: <SCRIPT
noindex_end: </SCRIPT>
no_next_page_text
type:
string
used by:
htsearch
default:
[next]
description:
The text displayed where there would normally be a hyperlink to go to the next page of matches.
example:
no_next_page_text:
no_page_list_header
type:
string
used by:
htsearch
default:
<empty>
description:
This text will be used as the value of the PAGEHEADER variable, for use in templates or the search_results_footer file, when all search results fit on a single page.
example:
no_page_list_header: <hr noshade size=2>All results on this page.<br>
no_page_number_text
type:
quoted string list
used by:
htsearch
default:
<empty>
description:
The text strings in this list will be used when putting together the PAGELIST variable, for use in templates or the search_results_footer file, when search results fit on more than page. The PAGELIST is the list of links at the bottom of the search results page. There should be as many strings in the list as there are pages allowed by the maximum_pages attribute. If there are not enough, or the list is empty, the page numbers alone will be used as the text for the links. An entry from this list is used for the current page, as the current page is shown in the page list without a hypertext link, while entries from the page_number_text list are used for the links to other pages. The text strings can contain HTML tags to highlight page numbers or embed images. The strings need to be quoted if they contain spaces.
example:
no_page_number_text: <strong>1</strong> <strong>2</strong> \
<strong>3</strong> <strong>4</strong> \
<strong>5</strong> <strong>6</strong> \
<strong>7</strong> <strong>8</strong> \
<strong>9</strong> <strong>10</strong>
no_prev_page_text
type:
string
used by:
htsearch
default:
[prev]
description:
The text displayed where there would normally be a hyperlink to go to the previous page of matches.
example:
no_prev_page_text:
nothing_found_file
type:
string
used by:
htsearch
default:
${common_dir}/nomatch.html
description:
This specifies the file which contains the HTML text to display when no matches were found. The file should contain a complete HTML document.
Note that this attribute could also be defined in terms of database_base to make is specific to the current search database.
example:
nothing_found_file: /www/searching/nothing.html
no_title_text
type:
string
used by:
htsearch
default:
filename
description:
This specifies the text to use in search results when no title is found in the document itself. If it is set to filename, htsearch will use the name of the file itself, enclosed in brackets (e.g. [index.html]).
example:
no_title_text: "No Title Found"
page_list_header
type:
string
used by:
htsearch
default:
<hr noshade size=2>Pages:<br>
description:
This text will be used as the value of the PAGEHEADER variable, for use in templates or the search_results_footer file, when all search results fit on more than one page.
example:
page_list_header:
page_number_text
type:
quoted string list
used by:
htsearch
default:
<empty>
description:
The text strings in this list will be used when putting together the PAGELIST variable, for use in templates or the search_results_footer file, when search results fit on more than page. The PAGELIST is the list of links at the bottom of the search results page. There should be as many strings in the list as there are pages allowed by the maximum_pages attribute. If there are not enough, or the list is empty, the page numbers alone will be used as the text for the links. Entries from this list are used for the links to other pages, while an entry from the no_page_number_text list is used for the current page, as the current page is shown in the page list without a hypertext link. The text strings can contain HTML tags to highlight page numbers or embed images. The strings need to be quoted if they contain spaces.
example:
page_number_text: <em>1</em> <em>2</em> \
<em>3</em> <em>4</em> \
<em>5</em> <em>6</em> \
<em>7</em> <em>8</em> \
<em>9</em> <em>10</em>
pdf_parser
type:
string
used by:
htdig
default:
acroread -toPostScript
description:
Set this to the path of the program used to parse PDF files, including all command-line options. The program will be called with the parameters:
infile outfile,
where infile is a file to parse and outfile is the PostScript output of the parser. In the case where acroread is the parser, and the -pairs option is not given, the second parameter will be the output directory rather than the output file name. The program is supposed to convert to a variant of PostScript, which is then parsed internally. Currently, only Adobe's acroread program has been tested as a pdf_parser. There is a bug in Acrobat 4's acroread command, which causes it to fail when -pairs is used, hence the special case above.
The pdftops program that is part of the xpdf package is not suitable as a pdf_parser, because its variant of PostScript is slightly different. However, an alternative is to use xpdf's pdftotext program as a component of an external parser with the xpdf 0.90 package installed on your system, as described in FAQ question 4.9.
In either case, to successfully index PDF files, be sure to set the max_doc_size attribute to a value larger than the size of your largest PDF file. PDF documents can not be parsed if they are truncated.

The default value of this attribute is determined at compile time, to include the path to the acroread executable.

example:
pdf_parser: /usr/local/Acrobat3/bin/acroread -toPostScript -pairs
prefix_match_character
type:
string
used by:
htsearch
default:
*
description:
A null prefix character means that prefix matching should be applied to every search word. Otherwise a match is returned only if the word does not end in the characters specified.
example:
prefix_match_character: ing
prev_page_text
type:
string
used by:
htsearch
default:
[prev]
description:
The text displayed in the hyperlink to go to the previous page of matches.
example:
prev_page_text: <img src="/htdig/buttonl.gif">
remove_bad_urls
type:
boolean
used by:
htmerge
default:
true
description:
If TRUE, htmerge will remove any URLs which were marked as unreachable by htdig from the database. If FALSE, it will not do this. When htdig is run in initial mode, documents which were referred to but could not be accessed should probably be removed, and hence this option should then be set to TRUE, however, if htdig is run to update the database, this may cause documents on a server which is temporarily unavailable to be removed. This is probably NOT what was intended, so hence this option should be set to FALSE in that case.
example:
remove_bad_urls: true
remove_default_doc
type:
string list
used by:
htdig
default:
index.html
description:
Set this to the default documents in a directory used by the servers you are indexing. These document names will be stripped off of URLs when they are normalized, if one of these names appears after the final slash, to translate URLs like http://foo.com/index.html into http://foo.com/
Note that you can disable stripping of these names during normalization by setting the list to an empty string. The list should only contain names that all servers you index recognize as default documents for directory URLs, as defined by the DirectoryIndex setting in Apache's srm.conf, for example.
example:
remove_default_doc: default.html default.htm index.html index.htm
or
remove_default_doc:
robotstxt_name
type:
string
used by:
htdig
default:
htdig
description:
Sets the name that htdig will look for when parsing robots.txt files. This can be used to make htdig appear as a different spider than ht://Dig. Useful to distinguish between a private and a global index.
example:
robotstxt_name: myhtdig
search_algorithm
type:
string list
used by:
htsearch
default:
exact:1
description:
Specifies the search algorithms and their weight to use when searching. Each entry in the list consists of the algorithm name, followed by a colon (:) followed by a weight multiplier. The multiplier is a floating point number between 0 and 1. Current algorithms supported are:
exact
The default exact word matching algorithm. This will find only exactly matched words.
soundex
Uses a slightly modified soundex algorithm to match words. This requires that the soundex database be present. It is generated with the htfuzzy program.
metaphone
Uses the metaphone algorithm for matching words. This algorithm is more specific to the english language than soundex. It is generated with the htfuzzy program.
endings
This algorithm uses language specific word endings to find matches. Each word is first reduced to its word root and then all known legal endings are used for the matching. This algorithm uses two databases which are generated with htfuzzy.
synonyms
Performs a dictionary lookup on all the words. This algorithm uses a database generated with the htfuzzy program.
substring
Matches all words containing the queries as substrings. Since this requires checking every word in the database, this can really slow down searches considerably.
prefix
Matches all words beginning with the query strings. Uses the option prefix_match_character to decide whether a query requires prefix matching. For example "abc*" would perform prefix matching on "abc" since * is the default prefix_match_character.
example:
search_algorithm: exact:1 soundex:0.3
search_results_footer
type:
string
used by:
htsearch
default:
${common_dir}/footer.html
description:
This specifies a filename to be output at the end of search results. While outputting the footer, some variables will be expanded. Variables use the same syntax as the Bourne shell. If there is a variable VAR, the following will all be recognized:
  • $VAR
  • $(VAR)
  • ${VAR}
The following variables are available:
MATCHES
The number of documents that were matched.
PLURAL_MATCHES
If MATCHES is not 1, this will be the string "s", else it is an empty string. This can be used to say something like "$(MATCHES) document$(PLURAL_MATCHES) were found"
MAX_MATCHES
The number of maximum displayed matches.
MAX_STARS
The value of the max_stars attribute.
LOGICAL_WORDS
A string of the search words with either "and" or "or" between the words, depending on the type of search.
WORDS
A string of the search words with spaces in between.
PAGEHEADER
This expands to either the value of the page_list_header or no_page_list_header attribute depending on how many pages there are.
Note that this file will NOT be output if no matches were found. In this case the nothing_found_file attribute is used instead. Also, this file will not be output if it is overridden by defining the search_results_wrapper attribute.
example:
search_results_footer: /usr/local/etc/ht/end-stuff.html
search_results_header
type:
string
used by:
htsearch
default:
${common_dir}/header.html
description:
This specifies a filename to be output at the start of search results. While outputting the header, some variables will be expanded. Variables use the same syntax as the Bourne shell. If there is a variable VAR, the following will all be recognized:
  • $VAR
  • $(VAR)
  • ${VAR}
The following variables are available:
MATCHES
The number of documents that were matched.
PLURAL_MATCHES
If MATCHES is not 1, this will be the string "s", else it is an empty string. This can be used to say something like "$(MATCHES) document$(PLURAL_MATCHES) were found"
MAX_MATCHES
The number of maximum displayed matches.
MAX_STARS
The value of the max_stars attribute.
LOGICAL_WORDS
A string of the search words with either "and" or "or" between the words, depending on the type of search.
WORDS
A string of the search words with spaces in between.
Note that this file will NOT be output if no matches were found. In this case the nothing_found_file attribute is used instead. Also, this file will not be output if it is overridden by defining the search_results_wrapper attribute.
example:
search_results_header: /usr/local/etc/ht/start-stuff.html
search_results_wrapper
type:
string
used by:
htsearch
default:
<empty>
description:
This specifies a filename to be output at the start and end of search results. This file replaces the search_results_header and search_results_footer files, with the contents of both in one file, and uses the pseudo-variable $(HTSEARCH_RESULTS) as a separator for the header and footer sections. If the filename is not specified, the file is unreadable, or the pseudo-variable above is not found, htsearch reverts to the separate header and footer files instead. While outputting the wrapper, some variables will be expanded, just as for the search_results_header and search_results_footer files.
Note that this file will NOT be output if no matches were found. In this case the nothing_found_file attribute is used instead.
example:
search_results_wrapper: ${common_dir}/wrapper.html
server_aliases
type:
string list
used by:
htdig
default:
<empty>
description:
This directive tells the indexer that servers have several DNS aliases, which all point to the same machine and are NOT virtual hosts. This allows you to ensure pages are indexed only once on a given machine, despite the alias used in a URL.
example:
server_aliases: foo.mydomain.com:80=www.mydomain.com:80 \
bar.mydomain.com:80=www.mydomain.com:80
server_max_docs
type:
integer
used by:
htdig
default:
-1 (no limit)
description:
This directive tells htdig to limit the dig to retrieve a maximum number of documents from each server. This can cause unusual behavior on update digs since the old URLs are stored alphabetically. Therefore, update digs will add additional URLs in pseudo-alphabetical order, up to the limit of the directive. However, it is most useful to partially index a server as the URLs of additional documents are entered into the database, marked as never retrieved.
example:
server_max_docs: 50
server_wait_time
type:
integer
used by:
htdig
default:
0
description:
This directive tells htdig to ensure a server has had a delay (in seconds) from the beginning of the last connection. This can be used to prevent "server abuse" by digging without delay. It's recommended to set this to 10-30 (seconds) when indexing servers that you don't monitor yourself. Additionally, this directive can slow down local indexing if set, which may or may not be what you intended.
example:
server_wait_time: 20
sort
type:
string
used by:
htsearch
default:
score
description:
This is the default sorting method that htsearch uses to determine the order in which matches are displayed. The valid choices are:
  • score
  • time
  • title
  • revscore
  • revtime
  • revtitle
This attribute will only be used if the HTML form that calls htsearch didn't have the sort value set. The words date and revdate can be used instead of time and revtime, as both will sort by the time that the document was last modified, if this information is given by the server. The default is to sort by the score, which ranks documents by best match. The sort methods that begin with "rev" simply reverse the order of the sort. Note that setting this to something other than "score" will incur a slowdown in searches.
example:
sort: revtime
sort_names
type:
quoted string list
used by:
htsearch
default:
score Score time Time title Title revscore 'Reverse Score' revtime 'Reverse Time' revtitle 'Reverse Title'
description:
These values are used to create the sort menu. It consists of pairs. The first element of each pair is one of the known sort methods, the second element is the text that will be shown in the menu for that sort method. This text needs to be quoted if it contains spaces.
example:
sort_names: score 'Best Match' time Newest title A-Z \
revscore 'Worst Match' revtime Oldest revtitle Z-A
soundex_db
type:
string
used by:
htfuzzy and htsearch
default:
${database_base}.soundex.db
description:
The database file used for the fuzzy "soundex" search algorithm. This database is created by htfuzzy and used by htsearch.
example:
soundex_db: ${database_base}.snd.db
star_blank
type:
string
used by:
htsearch
default:
${image_url_prefix}/star_blank.gif
description:
This specifies the URL to use to display a blank of the same size as the star defined in the image_star attribute or in the image_patterns attribute.
example:
star_blank: http://www.somewhere.org/icons/elephant.gif
star_image
type:
string
used by:
htsearch
default:
${image_url_prefix}/star.gif
description:
This specifies the URL to use to display a star. This allows you to use some other icon instead of a star. (We like the star...)
The display of stars can be turned on or off with the use_star_image attribute and the maximum number of stars that can be displayed is determined by the max_stars attribute.
Even though the image can be changed, the ALT value for the image will always be a '*'.
example:
star_image: http://www.somewhere.org/icons/elephant.gif
star_patterns
type:
string list
used by:
htsearch
default:
<empty>
description:
This attribute allows the star image to be changed depending on the URL or the match it is used for. This is mainly to make a visual distinction between matches on different web sites. The star image could be replaced with the logo of the company the match refers to.
It is advisable to keep all the images the same size in order to line things up properly in a short result listing.
The format is simple. It is a list of pairs. The first element of each pair is a pattern, the second element is a URL to the image for that pattern.
example:
star_patterns: http://www.sdsu.edu /sdsu.gif \
http://www.ucsd.edu /ucsd.gif
start_ellipses
type:
string
used by:
htsearch
default:
<b><tt>... </tt></b>
description:
When excerpts are displayed in the search output, this string will be prepended to the excerpt if there is text before the text displayed. This is just a visual reminder to the user that the excerpt is only part of the complete document.
example:
start_ellipses: ...
start_url
type:
string list
used by:
htdig
default:
http://www.htdig.org/
description:
This is the list of URLs that will be used to start a dig when there was no existing database. Note that multiple URLs can be given here.
example:
start_url: http://www.somewhere.org/alldata/index.html
substring_max_words
type:
integer
used by:
htsearch
default:
25
description:
The Substring fuzzy algorithm could potentially match a very large number of words. This value limits the number of words each substring pattern can match. Note that this does not limit the number of documents that are matched in any way.
example:
substring_max_words: 100
synonym_dictionary
type:
string
used by:
htfuzzy
default:
${common_dir}/synonyms
description:
This points to a text file containing the synonym dictionary used for the synonyms search algorithm.
Each line of this file has at least two words. The first word is the word to replace, the rest of the words are synonyms for that word.
example:
synonym_dictionary: /usr/dict/synonyms
synonym_db
type:
string
used by:
htsearch and htfuzzy
default:
${common_dir}/synonyms.db
description:
Points to the database that htfuzzy creates when the synonyms algorithm is used.
htsearch uses this to perform synonym dictionary lookups.
example:
synonym_db: ${database_base}.syn.db
syntax_error_file
type:
string
used by:
htsearch
default:
${common_dir}/syntax.html
description:
This points to the file which will be displayed if a boolean expression syntax error was found.
example:
syntax_error_file: ${common_dir}/synerror.html
template_map
type:
string list
used by:
htsearch
default:
Long builtin-long builtin-long Short builtin-short builtin-short
description:
This maps match template names to internal names and template file names. It is a list of triplets. The first element in each triplet is the name that will be displayed in the FORMAT menu. The second element is the name used internally and the third element is a filename of the template to use.
There are two predefined templates, namely builtin-long and builtin-short. If the filename is one of those, they will be used instead.
More information about templates can be found in the htsearch documentation.
example:
template_map: Short short ${common_dir}/short.html \
Normal normal builtin-long \
Detailed detail ${common_dir}/detail.html
template_name
type:
string
used by:
htsearch
default:
builtin-long
description:
Specifies the default template if none is given by the search form. This needs to map to the template_map.
example:
template_name: long
text_factor
type:
number
used by:
htdig
default:
1
description:
This is a factor which will be used to multiply the weight of words that are not in any special part of a document. Setting a factor to 0 will cause normal words to be ignored. The number may be a floating point number. See also the heading_factor_[1-6], title_factor, and keywords_factor attributes.
example:
text_factor: 0
timeout
type:
number
used by:
htdig
default:
30
description:
Specifies the time the digger will wait to complete a network read. This is just a safeguard against unforeseen things like the all too common transformation from a network to a notwork.
The timeout is specified in seconds.
example:
timeout: 42
title_factor
type:
number
used by:
htdig
default:
100
description:
This is a factor which will be used to multiply the weight of words in the title of a document. Setting a factor to 0 will cause words in the title to be ignored. The number may be a floating point number. See also the heading_factor_[1-6] attribute.
example:
title_factor: 12
translate_amp
type:
boolean
used by:
htdig
default:
false
description:
If set to false, the entity &amp; (or &#38;) will not be translated into its ASCII equivalent &. If translation were taking place, an excerpt containing a & might be misinterpreted by the browser and look unrecognizable to the user. For this reason, not translating this entity is the default behavior.
example:
translate_amp: true
translate_lt_gt
type:
boolean
used by:
htdig
default:
false
description:
If set to false, the entities &lt; (or &#60;) and &gt; (or &#62;) will not be translated into their ASCII equivalents < and >. If translation were taking place, an excerpt containing < and > might be misinterpreted by the browser and look unrecognizable to the user. For this reason, not translating these entities is the default behavior.
example:
translate_lt_gt: true
translate_quot
type:
boolean
used by:
htdig
default:
false
description:
If set to false, the entity &quot; (or &#34;) will not be translated into its ASCII equivalent ". If translation were taking place, an excerpt containing a " might be misinterpreted by the browser and look unrecognizable to the user. For this reason, not translating this entity is the default behavior.
example:
translate_quot: true
uncoded_db_compatible
type:
boolean
used by:
htdig, htnotify, htmerge and htsearch
default:
true
description:
At the cost of time for extra database accesses and not getting the full effect of the options common_url_parts and url_part_aliases, read databases where some or all URLs are not encoded at all through these options.
Note that the database still needs to be rebuilt if either or both of common_url_parts and url_part_aliases were non-empty when it was built or modified, or if they were set to anything else than the current values.
If a to-string in url_part_aliases can occur in normal URLs, this option should be set to false to eliminate surprises.
example:
uncoded_db_compatible: false

url_list
type:
string
used by:
htdig
default:
${database_base}.urls
description:
This file is only created if create_url_list is set to true. It will contain a list of all URLs that were seen.
example:
url_list: /tmp/urls
url_log
type:
string
used by:
htdig
default:
${database_base}.log
description:
If htdig is run with the -l option and interrupted, it will write out its progress to this file. Note that if it has a large number of URLs to write, it may take some time to exit. This can especially happen when running update digs and the run is interrupted soon after beginning.
example:
url_log: /tmp/htdig.progress
url_part_aliases
type:
string list
used by:
htdig, htnotify, htmerge and htsearch
default:
<empty>
description:
A list of translations pairs from and to, used when accessing the database. If a part of an URL matches with the from-string of each pair, it will be translated into the to-string just before writing the URL to the database, and translated back just after reading it from the database.
This is primarily used to provide an easy way to rename parts of URLs for e.g. changing www.example.com/~htdig to www.htdig.org. Two different configuration files for digging and searching are then used, with url_part_aliases having different from strings, but identical to-strings.
See also common_url_parts.
Strings that are normally incorrect in URLs or very seldom used, should be used as to-strings, since extra storage will be used each time one is found as normal part of a URL. Translations will be performed with priority for the leftmost longest match. Each to-string must be unique and not be a part of any other to-string.
Note that when this attribute is changed, the database should be rebuilt, unless the effect of "moving" the affected URLs in the database is wanted, as described above.
example:
url_part_aliases: http://search.example.com/~htdig *site \
http://www.htdig.org/this/ *1 \
.html *2
url_part_aliases: http://www.htdig.org/ *site \
http://www.htdig.org/that/ *1 \
.htm *2
use_meta_description
type:
boolean
used by:
htsearch
default:
false
description:
If set to true, any META description tags will be used as excerpts by htsearch. Any documents that do not have META descriptions will retain their normal excerpts.
example:
use_meta_description: true
use_star_image
type:
boolean
used by:
htsearch
default:
true
description:
If set to true, the star_image attribute is used to display upto max_stars images for each match.
example:
use_star_image: no
user_agent
type:
string
used by:
htdig
default:
htdig
description:
This allows customization of the user_agent: field sent when the digger requests a file from a server.
example:
user_agent: htdig-digger
valid_punctuation
type:
string
used by:
htdig and htsearch
default:
.-_/!#$%^&'
description:
This is the set of characters which will be deleted from the document before determining what a word is. This means that if a document contains something like Andrew's the digger will see this as Andrews.
The same transformation is performed on the keywords the search engine gets.
See also the extra_word_characters attribute.
example:
valid_punctuation: -'
version
type:
string
used by:
htsearch
default:
VERSION
description:
This specifies the value of the VERSION variable which can be used in search templates. The default value of this attribute is determined at compile time, and will not normally be set in configuration files.
example:
version: 3.1.2PL1
word_db
type:
string
used by:
htdig, htmerge and htsearch,
default:
${database_base}.words.db
description:
This is the main word database. It is an index of all the words to a list of documents that contain the words. This database can grow large pretty quickly.
example:
word_db: ${database_base}.allwords.db
word_list
type:
string
used by:
htdig and htmerge
default:
${database_base}.wordlist
description:
This is the input file that htmerge uses to create the main words database specified by word_db. This file gets about as large as the main words database. If this file exists when htdig is running, it will append data to this file. htmerge will then use the existing data and the appended data to create a completely new main word database.
example:
word_list: ${database_base}.allwords.text
Andrew Scherpbier <andrew@contigo.com>
Last modified: Fri Aug 6 15:00:15 EDT 1999