book.php File Reference

Search the library catalogue. More...

Go to the source code of this file.

Functions
	is_wildcard ($term)
	check for wildcards in search term
	normalize ($term)
	strip funny characters from a search term
	build_z3950_query ($search)
	build a Z3950 search term in RPN format
	grs_analyze ($grs)
	translate a Z39.50 result in GRS format to a more human-readable form
	book_info ($search)
	search in the library catalogue, using the Z39.50 protocol
Variables
	$grs_dict

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Detailed Description

Search the library catalogue.

These functions provide an interface to the library catalogue. It is possible to search for books in the catalogue and obtain bibliographic data from it, using the Z39.50 protocol.

Requires the PHP/YAZ module; see www.indexdata.dk/phpyaz for details.

Definition in file book.php.

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Function Documentation

book_info

(

$

search

)

search in the library catalogue, using the Z39.50 protocol

Parameters:

$search

The input parameter $search is an associative array containing key-value pairs. They represent a search term of the form (key_1 = value_1) AND (key_2 = value_2) AND ... .

Example: if you want to search for books about apples AND written by Newton, you would use:

$search = array ('title' => 'apple', 'author' => 'Newton')

Returns:

an associative array containing the results in human readable form.

Definition at line 235 of file book.php.

References build_z3950_query(), and grs_analyze().

Referenced by edit_item().

                            {
        global $z_host, $z_port, $z_auth, $z_db, $z_query;

        # connect to z39.50 server

        $z_url =  "$z_host:$z_port/$z_db";
        $z_opts = array("user" => $z_user, "password" => $z_pass);

        $z_handle = yaz_connect($z_url, $z_opts) or 
                user_error(yaz_error($z_handle), E_USER_ERROR);

        yaz_syntax($z_handle, "usmarc");        // choose usmarc syntax
        yaz_range($z_handle, 1,100);            // max. 100 results
        yaz_element($z_handle, "F");            // request "full" records

        # build query, perform search

        $z_query =build_z3950_query($search); 


        yaz_search($z_handle, "rpn", $z_query);

        yaz_wait() or
                user_error( yaz_error($z_handle), E_USER_ERROR);

        $ans = array();

        $i = 1;

        # analyze response, build answer 

        while ( $z_record = yaz_record($z_handle,$i++, "array")) {

                 $a = grs_analyze($z_record);
                # $a['signature'] = $sig;
                 $ans[] = $a;

        }

        yaz_close($z_handle);

        return $ans;
}

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build_z3950_query

(

$

search

)

build a Z3950 search term in RPN format

Build an string representation of a Z3950 query in RPN format (see the YAZ documentation for details).

Parameters:

$search

The input parameter $search is an associative array containing key-value pairs. They represent a search term of the form (key_1 = value_1) AND (key_2 = value_2) AND ....

Example:

$search = array ('title' => 'apple', 'author' => 'Newton')

means you want to search for books where title contains 'apple' AND author contains 'Newton'.

Wildcards at the end of a word are recognized, i.e. "appl*" will match 'apple' as well as 'application'.

Returns:

a search expression looking like this:

@and @attr 1=1017 "Apple" @attr 1=1017 "Newton"

Note that the search expression uses RPN (reverse polish notation) semantics, hence the "\@and" comes first.

The @attr x=y terms are search attributes, as defined in the BIB-1 standard. See http://www.loc.gov/z3950/agency/defns/bib1.html for details.

Note:

Due to quirks with the PICA library catalogue's Z39.50 server, we found it best to map both title and author to attribute 1017 ("any"). Your mileage may vary.

Definition at line 108 of file book.php.

References is_wildcard().

Referenced by book_info().

                                    {

        $i = 0;
        $z_query = "";


        foreach ($search as $key => $term) {

                if (empty($term)) {continue;}

                switch($key) {

                case "signature": 
                        $z_query .= '@or @attr 5=1 @attr 1=54 "';
                        $z_query .= normalize($term);
                        $z_query .= '" @attr 5=1 @attr 1=53 "';
                        $z_query .= normalize($term);
                        $z_query .= '" ';

                        $i++;
                        break;

                case "isbn":  

                        $z_query .= '@attr 5=1 @attr 1=7 "';
                        $z_query .= normalize($term);
                        $z_query .= '" ';

                        $i++;
                        break;

                case "author":  
                case "title":  

                        foreach (split(' ', $term) as $word) {

                                if (empty($term)) {continue;}
                                                
                                $z_query .= (is_wildcard($word)) ? 
                                                "@attr 5=1 " : "";

                                $z_query .= '@attr 1=1016 "';
                                $z_query .= normalize($word);
                                $z_query .= '" ';
                                $i++;
                        }
                        
                        break;
                }
        }

        while ($i > 1) {
                $z_query = "@and " . $z_query;
                $i--;
        }


        return $z_query;
}

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grs_analyze

(

$

grs

)

translate a Z39.50 result in GRS format to a more human-readable form

Parameters:

$grs

Z39.50 result in GRS format

Returns:

a human-readable associative array containing bibliographical

Note:

The array $grs_dict is used as a reference for this translation.

Definition at line 176 of file book.php.

References $grs_dict.

Referenced by book_info().

                           {
        global $grs_dict;

        $ans = array();

        foreach ($grs_dict as $key => $value )  {
                foreach ($grs as $rec)  {
                        if (preg_match($key, $rec[0])) {

                                $v = preg_replace("/[,\/ ]*$/","",$rec[1]);

                                # The PICA z39.50 server delivers
                                # the book signature mingled together with
                                # the book's location.  We strip the 
                                # location - which is enclosed in exclamation 
                                # marks - from the final result. 

                                if ($value == "signature") {
                                        $v = preg_replace("/![^!]*!/","",$v);
                                }

                                $ans[$value] .= "$v ; ";
                        }
                }

                # get rid of several semicolons, colons, commas, etc. in a row

                $ans[$value] = preg_replace("/;\s*;/",";",$ans[$value]);
                $ans[$value] = preg_replace("/:\s*;/",":",$ans[$value]);
                $ans[$value] = preg_replace("/\/\s*;/","/",$ans[$value]);
                $ans[$value] = preg_replace("/\.\s*;/",".",$ans[$value]);
        }


        $s = split(";", $ans[signature]);
        $ans[signature] = $s[0];        

        foreach ($ans as $key => $value) {
                $ans[$key] = trim($value, " ;" );
        }

        return $ans;
}

is_wildcard

(

$

term

)

check for wildcards in search term

Returns:

true if search term $term ends with a wildcard (?*)

Definition at line 48 of file book.php.

Referenced by build_z3950_query().

                             {
        return (preg_match('/[?*]\s*$/', $term) == 1 );
}

normalize

(

$

term

)

strip funny characters from a search term

Returns:

a "normalized" $term

Definition at line 55 of file book.php.

                          {

        setlocale(LC_CTYPE,'de_DE');

        # strip whitespace

        $term = preg_replace('/\s\s+/', ' ', $term);
        $term = trim($term);

        # strip non-word, non-space characters, e.g. comma, brace, etc.
        $term = preg_replace('/[^\w\s\/_-]/', '', $term);

        $term = strtolower($term);

        return $term;
}

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