repo_zf1/documentation/manual/en/module_specs/Zend_Http_Cookie-Handling.xml

<?xml version="1.0" encoding="UTF-8"?>
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<sect1 id="zend.http.cookies">
    <title>Zend_Http_Cookie and Zend_Http_CookieJar</title>

    <sect2 id="zend.http.cookies.introduction">
        <title>Introduction</title>

        <para>
            <classname>Zend_Http_Cookie</classname>, as expected, is a class that represents an
            <acronym>HTTP</acronym> cookie. It provides methods for parsing <acronym>HTTP</acronym>
            response strings, collecting cookies, and easily accessing their properties. It also
            allows checking if a cookie matches against a specific scenario, IE
            a request <acronym>URL</acronym>, expiration time, secure connection, etc.
        </para>

        <para>
            <classname>Zend_Http_CookieJar</classname> is an object usually used by
            <classname>Zend_Http_Client</classname> to hold a set of
            <classname>Zend_Http_Cookie</classname> objects. The idea is that if a
            <classname>Zend_Http_CookieJar</classname> object is attached to a
            <classname>Zend_Http_Client</classname> object, all cookies going from and into the
            client through <acronym>HTTP</acronym> requests and responses will be stored by the
            CookieJar object. Then, when the client will send another request, it will first ask the
            CookieJar object for all cookies matching the request. These will be added to the
            request headers automatically. This is highly useful in cases where you need to
            maintain a user session over consecutive <acronym>HTTP</acronym> requests, automatically
            sending the session ID cookies when required. Additionally, the
            <classname>Zend_Http_CookieJar</classname> object can be serialized and stored in
            $_SESSION when needed.
        </para>
    </sect2>

    <sect2 id="zend.http.cookies.cookie.instantiating">
        <title>Instantiating Zend_Http_Cookie Objects</title>

        <para>
            Instantiating a Cookie object can be done in two ways:

            <itemizedlist>
                <listitem>
                    <para>
                        Through the constructor, using the following syntax:
                        <code>new <classname>Zend_Http_Cookie</classname>(string $name, string
                            $value, string $domain, [int $expires, [string $path, [boolean
                            $secure]]]);</code>
                    </para>

                    <itemizedlist>
                        <listitem>
                            <para>
                                <varname>$name</varname>: The name of the cookie (eg. 'PHPSESSID')
                                (required)
                            </para>
                        </listitem>

                        <listitem>
                            <para>
                                <varname>$value</varname>: The value of the cookie (required)
                            </para>
                        </listitem>

                        <listitem>
                            <para>
                                <varname>$domain</varname>: The cookie's domain (eg. '.example.com')
                                (required)
                            </para>
                        </listitem>

                        <listitem>
                            <para>
                                <varname>$expires</varname>: Cookie expiration time, as UNIX time
                                stamp (optional, defaults to <constant>NULL</constant>). If not set,
                                cookie will be treated as a 'session cookie' with no expiration
                                time.
                            </para>
                        </listitem>

                        <listitem>
                            <para>
                                <varname>$path</varname>: Cookie path, eg. '/foo/bar/' (optional,
                                defaults to '/')
                            </para>
                        </listitem>

                        <listitem>
                            <para>
                                <varname>$secure</varname>: Boolean, Whether the cookie is to be
                                sent over secure (HTTPS) connections only (optional, defaults to
                                boolean <constant>FALSE</constant>)
                            </para>
                        </listitem>
                    </itemizedlist>
                </listitem>

                <listitem>
                    <para>
                        By calling the fromString() static method, with a cookie string as
                        represented in the 'Set-Cookie' <acronym>HTTP</acronym> response header or
                        'Cookie' <acronym>HTTP</acronym> request header. In this case, the cookie
                        value must already be encoded. When the cookie string does not contain a
                        'domain' part, you must provide a reference <acronym>URI</acronym> according
                        to which the cookie's domain and path will be set.
                    </para>
                </listitem>
            </itemizedlist>

            <example id="zend.http.cookies.cookie.instantiating.example-1">
               <title>Instantiating a Zend_Http_Cookie object</title>

               <programlisting language="php"><![CDATA[
// First, using the constructor. This cookie will expire in 2 hours
$cookie = new Zend_Http_Cookie('foo',
                               'bar',
                               '.example.com',
                               time() + 7200,
                               '/path');

// You can also take the HTTP response Set-Cookie header and use it.
// This cookie is similar to the previous one, only it will not expire, and
// will only be sent over secure connections
$cookie = Zend_Http_Cookie::fromString('foo=bar; domain=.example.com; ' .
                                       'path=/path; secure');

// If the cookie's domain is not set, you have to manually specify it
$cookie = Zend_Http_Cookie::fromString('foo=bar; secure;',
                                       'http://www.example.com/path');
]]></programlisting>
            </example>

            <note>
                <para>
                    When instantiating a cookie object using the
                    <classname>Zend_Http_Cookie</classname>::fromString() method, the cookie value
                    is expected to be <acronym>URL</acronym> encoded, as cookie strings should be.
                    However, when using the constructor, the cookie value string is expected to be
                    the real, decoded value.
                </para>
            </note>
        </para>

        <para>
            A cookie object can be transferred back into a string, using the __toString() magic
            method. This method will produce a HTTP request "Cookie" header string, showing the
            cookie's name and value, and terminated by a semicolon (';').
            The value will be URL encoded, as expected in a Cookie header:
            <example id="zend.http.cookies.cookie.instantiating.example-2">
               <title>Stringifying a Zend_Http_Cookie object</title>

               <programlisting language="php"><![CDATA[
// Create a new cookie
$cookie = new Zend_Http_Cookie('foo',
                               'two words',
                               '.example.com',
                               time() + 7200,
                               '/path');

// Will print out 'foo=two+words;' :
echo $cookie->__toString();

// This is actually the same:
echo (string) $cookie;

// In PHP 5.2 and higher, this also works:
echo $cookie;
]]></programlisting>
            </example>
        </para>
    </sect2>

    <sect2 id="zend.http.cookies.cookie.accessors">
        <title>Zend_Http_Cookie getter methods</title>

        <para>
            Once a <classname>Zend_Http_Cookie</classname> object is instantiated, it provides
            several getter methods to get the different properties of the <acronym>HTTP</acronym>
            cookie:

            <itemizedlist>
                <listitem>
                    <para>
                        <code>string getName()</code>: Get the name of the cookie
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <code>string getValue()</code>: Get the real, decoded value of the cookie
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <code>string getDomain()</code>: Get the cookie's domain
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <code>string getPath()</code>: Get the cookie's path, which defaults to '/'
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <code>int getExpiryTime()</code>: Get the cookie's expiration time, as UNIX
                        time stamp. If the cookie has no expiration time set, will return
                        <constant>NULL</constant>.
                    </para>
                </listitem>
            </itemizedlist>
        </para>

        <para>
            Additionally, several boolean tester methods are provided:

            <itemizedlist>
                <listitem>
                    <para>
                        <code>boolean isSecure()</code>: Check whether the cookie is set to be sent
                        over secure connections only. Generally speaking, if
                        <constant>TRUE</constant> the cookie should only be sent over
                        <acronym>HTTPS</acronym>.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <code>boolean isExpired(int $time = null)</code>: Check whether the cookie
                        is expired or not. If the cookie has no expiration time, will always return
                        <constant>TRUE</constant>. If $time is provided, it will override the
                        current time stamp as the time to check the cookie against.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <code>boolean isSessionCookie()</code>: Check whether the cookie is a
                        "session cookie" - that is a cookie with no expiration time, which is meant
                        to expire when the session ends.
                    </para>
                </listitem>
            </itemizedlist>
        </para>

        <para>
            <example id="zend.http.cookies.cookie.accessors.example-1">
                <title>Using getter methods with Zend_Http_Cookie</title>

                <programlisting language="php"><![CDATA[
// First, create the cookie
$cookie =
    Zend_Http_Cookie::fromString('foo=two+words; ' +
                                 'domain=.example.com; ' +
                                 'path=/somedir; ' +
                                 'secure; ' +
                                 'expires=Wednesday, 28-Feb-05 20:41:22 UTC');

echo $cookie->getName();   // Will echo 'foo'
echo $cookie->getValue();  // will echo 'two words'
echo $cookie->getDomain(); // Will echo '.example.com'
echo $cookie->getPath();   // Will echo '/'

echo date('Y-m-d', $cookie->getExpiryTime());
// Will echo '2005-02-28'

echo ($cookie->isExpired() ? 'Yes' : 'No');
// Will echo 'Yes'

echo ($cookie->isExpired(strtotime('2005-01-01') ? 'Yes' : 'No');
// Will echo 'No'

echo ($cookie->isSessionCookie() ? 'Yes' : 'No');
// Will echo 'No'
]]></programlisting>
            </example>
        </para>
    </sect2>

    <sect2 id="zend.http.cookies.cookie.matching">
        <title>Zend_Http_Cookie: Matching against a scenario</title>

        <para>
            The only real logic contained in a <classname>Zend_Http_Cookie</classname> object, is in
            the match() method. This method is used to test a cookie against a given
            <acronym>HTTP</acronym> request scenario, in order to tell whether the cookie should be
            sent in this request or not. The method has the following syntax and parameters:
            <code>boolean Zend_Http_Cookie->match(mixed $uri, [boolean $matchSessionCookies, [int
                $now]]);</code>

            <itemizedlist>
                <listitem>
                    <para>
                        <code>mixed $uri</code>: A <classname>Zend_Uri_Http</classname> object with
                        a domain name and path to be checked. Optionally, a string representing a
                        valid <acronym>HTTP</acronym> <acronym>URL</acronym> can be passed instead.
                        The cookie will match if the <acronym>URL</acronym>'s scheme (HTTP or
                        <acronym>HTTPS</acronym>), domain and path all match.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <code>boolean $matchSessionCookies</code>: Whether session cookies should be
                        matched or not. Defaults to <constant>TRUE</constant>. If set to
                        <constant>FALSE</constant>, cookies with no expiration time will never
                        match.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <code>int $now</code>: Time (represented as UNIX time stamp) to check a
                        cookie against for expiration. If not specified, will default to the current
                        time.
                    </para>
                </listitem>
            </itemizedlist>

            <example id="zend.http.cookies.cookie.matching.example-1">
                <title>Matching cookies</title>

                <programlisting language="php"><![CDATA[
// Create the cookie object - first, a secure session cookie
$cookie = Zend_Http_Cookie::fromString('foo=two+words; ' +
                                       'domain=.example.com; ' +
                                       'path=/somedir; ' +
                                       'secure;');

$cookie->match('https://www.example.com/somedir/foo.php');
// Will return true

$cookie->match('http://www.example.com/somedir/foo.php');
// Will return false, because the connection is not secure

$cookie->match('https://otherexample.com/somedir/foo.php');
// Will return false, because the domain is wrong

$cookie->match('https://example.com/foo.php');
// Will return false, because the path is wrong

$cookie->match('https://www.example.com/somedir/foo.php', false);
// Will return false, because session cookies are not matched

$cookie->match('https://sub.domain.example.com/somedir/otherdir/foo.php');
// Will return true

// Create another cookie object - now, not secure, with expiration time
// in two hours
$cookie = Zend_Http_Cookie::fromString('foo=two+words; ' +
                                       'domain=www.example.com; ' +
                                       'expires='
                                       . date(DATE_COOKIE, time() + 7200));

$cookie->match('http://www.example.com/');
// Will return true

$cookie->match('https://www.example.com/');
// Will return true - non secure cookies can go over secure connections
// as well!

$cookie->match('http://subdomain.example.com/');
// Will return false, because the domain is wrong

$cookie->match('http://www.example.com/', true, time() + (3 * 3600));
// Will return false, because we added a time offset of +3 hours to
// current time
]]></programlisting>
            </example>
        </para>
    </sect2>

    <sect2 id="zend.http.cookies.cookiejar">
        <title>The Zend_Http_CookieJar Class: Instantiation</title>

        <para>
            In most cases, there is no need to directly instantiate a
            <classname>Zend_Http_CookieJar</classname> object. If you want to attach a new cookie
            jar to your <classname>Zend_Http_Client</classname> object, just call the
            Zend_Http_Client->setCookieJar() method, and a new, empty cookie jar
            will be attached to your client. You could later get this cookie jar
            using Zend_Http_Client->getCookieJar().
        </para>

        <para>
            If you still wish to manually instantiate a CookieJar object, you
            can do so by calling "new Zend_Http_CookieJar()" directly - the
            constructor method does not take any parameters. Another way to
            instantiate a CookieJar object is to use the static Zend_Http_CookieJar::fromResponse()
            method. This method takes two parameters: a <classname>Zend_Http_Response</classname>
            object, and a reference <acronym>URI</acronym>, as either a string or a
            <classname>Zend_Uri_Http</classname> object. This method will return a new
            <classname>Zend_Http_CookieJar</classname> object, already containing the cookies set by
            the passed <acronym>HTTP</acronym> response. The reference <acronym>URI</acronym> will
            be used to set the cookie's domain and path, if they are not defined in the Set-Cookie
            headers.
        </para>
    </sect2>

    <sect2 id="zend.http.cookies.cookiejar.adding_cookies">
        <title>Adding Cookies to a Zend_Http_CookieJar object</title>

        <para>
            Usually, the <classname>Zend_Http_Client</classname> object you attached your CookieJar
            object to will automatically add cookies set by <acronym>HTTP</acronym> responses to
            your jar. if you wish to manually add cookies to your jar, this can be done by using
            two methods:

            <itemizedlist>
                <listitem>
                    <para>
                        <classname>Zend_Http_CookieJar->addCookie($cookie[, $ref_uri])</classname>:
                        Add a single cookie to the jar. $cookie can be either a
                        <classname>Zend_Http_Cookie</classname> object or a string, which will be
                        converted automatically into a Cookie object. If a string is provided, you
                        should also provide $ref_uri - which is a reference <acronym>URI</acronym>
                        either as a string or <classname>Zend_Uri_Http</classname> object, to use as
                        the cookie's default domain and path.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <classname>Zend_Http_CookieJar->addCookiesFromResponse($response,
                            $ref_uri)</classname>: Add all cookies set in a single
                        <acronym>HTTP</acronym> response to the jar. $response is expected to be a
                        <classname>Zend_Http_Response</classname> object with Set-Cookie headers.
                        $ref_uri is the request <acronym>URI</acronym>, either as a string or a
                        <classname>Zend_Uri_Http</classname> object, according to which the cookies'
                        default domain and path will be set.
                    </para>
                </listitem>
            </itemizedlist>
        </para>
    </sect2>

    <sect2 id="zend.http.cookies.cookiejar.getting_cookies">
        <title>Retrieving Cookies From a Zend_Http_CookieJar object</title>

        <para>
            Just like with adding cookies, there is usually no need to manually
            fetch cookies from a CookieJar object. Your <classname>Zend_Http_Client</classname>
            object will automatically fetch the cookies required for an <acronym>HTTP</acronym>
            request for you. However, you can still use 3 provided methods to fetch
            cookies from the jar object: <methodname>getCookie()</methodname>,
            <methodname>getAllCookies()</methodname>, and
            <methodname>getMatchingCookies()</methodname>. Additionnaly, iterating over the
            CookieJar will let you retrieve all the <classname>Zend_Http_Cookie</classname> objects
            from it.
        </para>

        <para>
            It is important to note that each one of these methods takes a
            special parameter, which sets the return type of the method. This
            parameter can have 3 values:

            <itemizedlist>
                <listitem>
                    <para>
                        <constant>Zend_Http_CookieJar::COOKIE_OBJECT</constant>: Return
                        a <classname>Zend_Http_Cookie</classname> object. If the method returns more
                        than one cookie, an array of objects will be returned.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <constant>Zend_Http_CookieJar::COOKIE_STRING_ARRAY</constant>: Return
                        cookies as strings, in a "foo=bar" format, suitable for sending
                        in a <acronym>HTTP</acronym> request "Cookie" header. If more than one
                        cookie is returned, an array of strings is returned.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <constant>Zend_Http_CookieJar::COOKIE_STRING_CONCAT</constant>: Similar to
                        COOKIE_STRING_ARRAY, but if more than one cookie is returned, this
                        method will concatenate all cookies into a single, long string
                        separated by semicolons (;), and return it. This is especially useful
                        if you want to directly send all matching cookies in a single
                        <acronym>HTTP</acronym> request "Cookie" header.
                    </para>
                </listitem>
            </itemizedlist>
        </para>

        <para>
            The structure of the different cookie-fetching methods is described below:

            <itemizedlist>
                <listitem>
                    <para>
                        <classname>Zend_Http_CookieJar->getCookie($uri, $cookie_name[,
                            $ret_as])</classname>: Get a single cookie from the jar, according to
                        its <acronym>URI</acronym> (domain and path) and name. $uri is either a
                        string or a <classname>Zend_Uri_Http</classname> object representing the
                        <acronym>URI</acronym>. $cookie_name is a string identifying the cookie
                        name. $ret_as specifies the return type as described above. $ret_type is
                        optional, and defaults to COOKIE_OBJECT.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <classname>Zend_Http_CookieJar->getAllCookies($ret_as)</classname>: Get all
                        cookies from the jar. $ret_as specifies the return type as described
                        above. If not specified, $ret_type defaults to COOKIE_OBJECT.
                    </para>
                </listitem>

                <listitem>
                    <para>
                        <classname>Zend_Http_CookieJar->getMatchingCookies($uri[,
                            $matchSessionCookies[, $ret_as[, $now]]])</classname>: Get all cookies
                        from the jar that match a specified scenario, that is a
                        <acronym>URI</acronym> and expiration time.

                        <itemizedlist>
                            <listitem>
                                <para>
                                    <varname>$uri</varname> is either a
                                    <classname>Zend_Uri_Http</classname> object or a string
                                    specifying the connection type (secure or non-secure), domain
                                    and path to match against.
                                </para>
                            </listitem>

                            <listitem>
                                <para>
                                    <varname>$matchSessionCookies</varname> is a boolean telling
                                    whether to match session cookies or not. Session cookies are
                                    cookies that have no specified expiration time. Defaults to
                                    <constant>TRUE</constant>.
                                </para>
                            </listitem>

                            <listitem>
                                <para>
                                    <varname>$ret_as</varname> specifies the return type as
                                    described above. If not specified, defaults to COOKIE_OBJECT.
                                </para>
                            </listitem>

                            <listitem>
                                <para>
                                    <varname>$now</varname> is an integer representing the UNIX time
                                    stamp to consider as "now" - that is any cookies who are set to
                                    expire before this time will not be matched. If not specified,
                                    defaults to the current time.
                                </para>
                            </listitem>
                        </itemizedlist>

                        You can read more about cookie matching here:
                        <xref linkend="zend.http.cookies.cookie.matching" />.
                    </para>
                </listitem>
            </itemizedlist>
        </para>
    </sect2>
</sect1>
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