Manual do PHP
Anterior |  | Próxima

# CLXXXV. YAZ Functions

# Introdução

This extension offers a PHP interface to the YAZ toolkit that implements the Z39.50 Protocol for Information Retrieval. With this extension you can easily implement a Z39.50 origin (client) that searches or scans Z39.50 targets (servers) in parallel.

The module hides most of the complexity of Z39.50 so it should be fairly easy to use. It supports persistent stateless connections very similar to those offered by the various RDB APIs that are available for PHP. This means that sessions are stateless but shared among users, thus saving the connect and initialize phase steps in most cases.

YAZ is available at http://www.indexdata.dk/yaz/. You can find news information, example scripts, etc. for this extension at http://www.indexdata.dk/phpyaz/.

> Nota: Esta extensão foi movida para o repositório PECL e não é mais distribuida em conjunto com o PHP a partir do PHP 5.0.0.

# Instalação

Obtain YAZ (ANSI/NISO Z39.50 support) and install it. YAZ can be fetched in source or in various prebuilt packages from the YAZ archive. Systems such as Debian GNU/Linux, Suse Linux, FreeBSD also has YAZ as part of their distribution.

For the PHP 4 series, the YAZ extension is bundled (but not YAZ itself) Build PHP with your favorite modules and add option `--with-yaz[=DIR]`.

Exemplo 1. YAZ compilation for PHP 4 on Unix
    gunzip -c php-4.4.X.tar.gz|tar xf -
    gunzip -c yaz-2.1.8.tar.gz|tar xf -
    cd yaz-2.1.8
    ./configure --prefix=/usr
    make
    sudo make install
    cd ../php-4.4.X.
    ./configure --with-yaz=/usr/bin
    make
    sudo make install

For PHP 5, the YAZ extension is in PECL and is installed as a shared object/dll. If you have pear installed the easiest way to download, configure and install the YAZ extension is by using the pecl command.

Installation of YAZ on Linux

Informações para a instalação desta extensão PECL podem ser encontradas no manual no capitulo entitulado Instalação de extensões PECL. Informações adicionais como novas versões, downloads, arquivos fontes, manutenções, e um Changelog, podem ser obtidos aqui: http://pecl.php.netyaz

Installation on Windows systems

Você pode baixar esta extensão PECL DLL a apartir de downloads PHP ou em http://snaps.php.net/. `php_yaz.dll` depends on `yaz.dll`. The `yaz.dll` is part of the Win32 ZIP from the PHP site. It is also part of the Windows YAZ install available from the YAZ WIN32 area.

Atenção
The PHP 5.0.5 Win32 zip includes a too old version of `yaz.dll` (version 1.9.1 < required version 2.0.13). If that's the case use the `yaz.dll` from a newer YAZ WIN32 install.

On windows, don't forget to add the PHP directory to the PATH, so that the `yaz.dll` file can be found by the system.

If you are using YAZ as a shared extension, add (or uncomment) the following line in `php.ini` on Unix:

    extension=yaz.so

And for Windows:

    extension=php_yaz.dll

Atenção
A extensão IMAP não pode ser utilizada em conjunto com as extensões recode, YAZ ou Cyrus. Isto ocorre pelo fato de elas compartilham os mesmos símbolos internos.

> Nota: The above problem is solved in version 2.0 of YAZ.

# Configurações em execução

O comportamento dessas funções podem ser modificado pelas configurações do `php.ini`.

Tabela 1. YAZ configuration options

Name | Default | Changeable | Changelog
--- | --- | --- | ---
yaz.max_links | "100" | PHP_INI_ALL | Available since PHP 4.3.0.
yaz.log_file | NULL | PHP_INI_ALL | Available since PHP 4.3.0.

Para mais detalhes e definições das constantes PHP_INI_*, veja Apêndice H.

# Tipos Resource

Esta extensão não possui nenhum tipo resource.

# Constantes pré-definidas

Esta extensão não possui nenhuma constante.

# Exemplos

PHP/YAZ keeps track of connections with targets (Z-Associations). A resource represents a connection to a target.

The script below demonstrates the parallel searching feature of the API. When invoked with no arguments it prints a query form; else (arguments are supplied) it searches the targets as given in array `host`.

Exemplo 2. Parallel searching using Yaz
`<?php $host=$_REQUEST[host]; $query=$_REQUEST[query]; $num_hosts = count($host); if (empty($query) || count($host) == 0) { echo '<form method="get"> <input type="checkbox" name="host[]" value="bagel.indexdata.dk/gils" /> GILS test <input type="checkbox" name="host[]" value="localhost:9999/Default" /> local test <input type="checkbox" checked="checked" name="host[]" value="z3950.loc.gov:7090/voyager" /> Library of Congress <br /> RPN Query: <input type="text" size="30" name="query" /> <input type="submit" name="action" value="Search" /> </form> '; } else { echo 'You searched for ' . htmlspecialchars($query) . '<br />'; for ($i = 0; $i < $num_hosts; $i++) { $id[] = yaz_connect($host[$i]); yaz_syntax($id[$i], "usmarc"); yaz_range($id[$i], 1, 10); yaz_search($id[$i], "rpn", $query); } yaz_wait(); for ($i = 0; $i < $num_hosts; $i++) { echo '<hr />' . $host[$i] . ':'; $error = yaz_error($id[$i]); if (!empty($error)) { echo "Error: $error"; } else { $hits = yaz_hits($id[$i]); echo "Result Count $hits"; } echo '<dl>'; for ($p = 1; $p <= 10; $p++) { $rec = yaz_record($id[$i], $p, "string"); if (empty($rec)) continue; echo "<dt><b>$p</b></dt><dd>"; echo nl2br($rec); echo "</dd>"; } echo '</dl>'; } } ?>`

Anterior | Principal | Próxima
xslt_setopt | Acima | yaz_addinfo