Using the grep Target

As a demonstration of the target API, gazelle includes a target which uses the UNIX command "grep" to search the files in a directory for a certain string or pattern, and returns the files as records.

To use the grep target, simply build gazelle with it. Go to the top level of the gazelle distribution and type

% make grep

The targets/grep directory contains a very simple example configuration file called grep.xml, which looks like this:

<config> <param name="port" value="2210"/> <param name="type" value="forking"/> <param name="debug" value="true"/> <param name="debugLog" value="debug.log"/> <param name="accessLog" value="access.log"/> <param name="errorLog" value="error.log"/> <!-- put the name of the directory you want to search here. include the trailing slash. --> <param name="grep_directory" value="/my/grep/directory/"/>

For instance, if you wanted to search the documents in the /home/httpd/htdocs directory, this line would read <param name="grep_directory" value="/home/httpd/htdocs/"/>

<!-- when you search with zclient, use "grep" as the name of the database --> <database name="grep"> <!-- Mapping of z39.50 terms and operators to target expressions. Currently, each attr or nested attr combination must have a "term" tag that defines how to build the term (the z39.50 attributePlusTerm) of an expression. Each attribute may also optionally have a "template" tag which defines how it is translated. --> <!-- For now, we only support attribute 1=1 --> <attr type="1" value="1"> <term>$value</term> </attr> </database> </config>

Select a directory you want to search and edit grep.xml appropriately. Then start gazelle. Next, try out the grep target using zclient. Pick a word which you know occurs in at least one file. Type

% ./zclient -a 1=1 grep word

The grep target should report the number of files which contain that word. See Using the Gazelle Client for information on how to use zclient.

For details about how the grep target works, see the tutorial on how to develop targets.