Provided by: libsoap-lite-perl_1.09-1_all 
NAME
SOAP::SOM - provides access to the values contained in SOAP Response
DESCRIPTION
Objects from the SOAP::SOM class aren't generally instantiated directly by an application.
Rather, they are handed back by the deserialization of a message. In other words,
developers will almost never do this:
$som = SOAP::SOM->new;
SOAP::SOM objects are returned by a SOAP::Lite call in a client context. For example:
my $client = SOAP::Lite
->readable(1)
->uri($NS)
->proxy($HOST)
$som = $client->someMethod();
METHODS
new(message)
$som = SOAP::SOM->new($message_as_xml);
As said, the need to actually create an object of this class should be very rare.
However, if the need arises, the syntax must be followed. The single argument to new
must be a valid XML document the parser will understand as a SOAP response.
The following group of methods provide general data retrieval from the SOAP::SOM object.
The model for this is an abbreviated form of XPath. Following this group are methods that
are geared towards specific retrieval of commonly requested elements.
match(path)
$som->match('/Envelope/Body/[1]');
This method sets the internal pointers within the data structure so that the retrieval
methods that follow will have access to the desired data. In the example path, the
match is being made against the method entity, which is the first child tag of the
body in a SOAP response. The enumeration of container children starts at 1 in this
syntax, not 0. The returned value is dependent on the context of the call. If the call
is made in a boolean context (such as "if ($som->match($path))"), the return value is
a boolean indicating whether the requested path matched at all. Otherwise, an object
reference is returned. The returned object is also a SOAP::SOM instance but is
smaller, containing the subset of the document tree matched by the expression.
valueof(node)
$res = $som->valueof('[1]');
When the SOAP::SOM object has matched a path internally with the match method, this
method allows retrieval of the data within any of the matched nodes. The data comes
back as native Perl data, not a class instance (see dataof). In a scalar context, this
method returns just the first element from a matched node set. In an array context,
all elements are returned. Assuming that the earlier call happens after the earlier
call to match, it retrieves the result entity from the method response that is
contained in $som, as this is the first child element in a method-response tag.
dataof(node)
$resobj = $som->dataof('[1]');
Performs the same operation as the earlier valueof method, except that the data is
left in its SOAP::Data form, rather than being deserialized. This allows full access
to all the attributes that were serialized along with the data, such as namespace and
encoding.
headerof(node)
$resobj = $som->headerof('[1]');
Acts much like dataof, except that it returns an object of the SOAP::Header class
(covered later in this chapter), rather than SOAP::Data. This is the preferred
interface for manipulating the header entities in a message.
namespaceuriof(node)
$ns = $som->namespaceof('[1]');
Retrieves the namespace URI that governs the requested node. Note that namespaces are
inherited, so this method will return the relevant value, even if it derives from a
parent or other ancestor node.
The following methods provide more direct access to the message envelope. All these
methods return some form of a Perl value, most often a hash reference, when called.
Context is also relevant: in a scalar context only the first matching node is returned,
while in an array context, all matching nodes are. When called as a static method or as a
regular function (such as "SOAP::SOM::envelope"), any of the following methods returns the
XPath string that is used with the match method to retrieve the data.
root
$root = $som->root;
Returns the value of the root element as a hash reference. It behaves exactly as
"$som-"valueof('/')> does.
envelope
$envelope = $som->envelope;
Retrieves the "Envelope" element of the message, returning it and its data as a hash
reference. Keys in the hash will be Header and Body (plus any optional elements that
may be present in a SOAP 1.1 envelope), whose values will be the serialized header and
body, respectively.
header
$header = $som->header;
Retrieves the header portion of the envelope as a hash reference. All data within it
will have been deserialized. If the attributes of the header are desired, the static
form of the method can be combined with match to fetch the header as a SOAP::Data
object:
$header = $som->match(SOAP::SOM::header)->dataof;
headers
@hdrs = $som->headers;
Retrieves the node set of values with deserialized headers from within the Header
container. This is different from the earlier header method in that it returns the
whole header as a single structure, and this returns the child elements as an array.
In other words, the following expressions yield the same data structure:
$header = ($som->headers)[0];
$header = $som->valueof(SOAP::SOM::header.'/[1]');
body
$body = $som->body;
Retrieves the message body as a hash reference. The entity tags act as keys, with
their deserialized content providing the values.
fault
if ($som->fault) { die $som->fault->faultstring }
Acts both as a boolean test whether a fault occurred, and as a way to retrieve the
Fault entity itself from the message body as a hash reference. If the message contains
a fault, the next four methods (faultcode, faultstring, faultactor, and faultdetail)
may be used to retrieve the respective parts of the fault (which are also available on
the hash reference as keys). If fault in a boolean context is true, the "result",
"paramsin", "paramsout", and "method" methods all return "undef".
faultcode
$code = $som->faultcode;
Returns the faultcode element of the fault if there is a fault; undef otherwise.
faultstring
$string = $som->faultstring;
Returns the faultstring element of the fault if there is a fault; undef otherwise.
faultactor
$actor = $som->faultactor;
Returns the faultactor element of the fault, if there is a fault and if the actor was
specified within it. The faultactor element is optional in the serialization of a
fault, so it may not always be present. This element is usually a string.
faultdetail
$detail = $som->faultdetail;
Returns the content of the detail element of the fault, if there is a fault and if the
detail element was provided. Note that the name of the element isn't the same as the
method, due to the possibility for confusion had the method been called simply,
detail. As with the faultactor element, this isn't always a required component of a
fault, so it isn't guaranteed to be present. The specification for the detail portion
of a fault calls for it to contain a series of element tags, so the application may
expect a hash reference as a return value when detail information is available (and
undef otherwise).
method
$method = $som->method
Retrieves the "method" element of the message, as a hash reference. This includes all
input parameters when called on a request message or all result/output parameters when
called on a response message. If there is a fault present in the message, it returns
undef.
result
$value = $som->result;
Returns the value that is the result of a SOAP response. The value will be already
deserialized into a native Perl datatype.
paramsin
@list = $som->paramsin;
Retrieves the parameters being passed in on a SOAP request. If called in a scalar
context, the first parameter is returned. When called in a list context, the full list
of all parameters is returned. Each parameter is a hash reference, following the
established structure for such return values.
paramsout
@list = $som->paramsout;
Returns the output parameters from a SOAP response. These are the named parameters
that are returned in addition to the explicit response entity itself. It shares the
same scalar/list context behavior as the paramsin method.
paramsall
@list = $som->paramsall;
Returns all parameters from a SOAP response, including the result entity itself, as
one array.
parts()
Return an array of "MIME::Entity"'s if the current payload contains attachments, or
returns undefined if payload is not MIME multipart.
is_multipart()
Returns true if payload is MIME multipart, false otherwise.
EXAMPLES
ACCESSING ELEMENT VALUES
Suppose for the following SOAP Envelope:
<Envelope>
<Body>
<fooResponse>
<bar>abcd</bar>
</fooResponse>
</Body>
</Envelope>
And suppose you wanted to access the value of the bar element, then use the following
code:
my $soap = SOAP::Lite
->uri($SOME_NS)
->proxy($SOME_HOST);
my $som = $soap->foo();
print $som->valueof('//fooResponse/bar');
ACCESSING ATTRIBUTE VALUES
Suppose the following SOAP Envelope:
<Envelope>
<Body>
<c2fResponse>
<convertedTemp test="foo">98.6</convertedTemp>
</c2fResponse>
</Body>
</Envelope>
Then to print the attribute 'test' use the following code:
print "The attribute is: " .
$som->dataof('//c2fResponse/convertedTemp')->attr->{'test'};
ITERATING OVER AN ARRAY
Suppose for the following SOAP Envelope:
<Envelope>
<Body>
<catalog>
<product>
<title>Programming Web Service with Perl</title>
<price>$29.95</price>
</product>
<product>
<title>Perl Cookbook</title>
<price>$49.95</price>
</product>
</catalog>
</Body>
</Envelope>
If the SOAP Envelope returned contained an array, use the following code to iterate over
the array:
for my $t ($som->valueof('//catalog/product')) {
print $t->{title} . " - " . $t->{price} . "\n";
}
DETECTING A SOAP FAULT
A SOAP::SOM object is returned by a SOAP::Lite client regardless of whether the call
succeeded or not. Therefore, a SOAP Client is responsible for determining if the returned
value is a fault or not. To do so, use the fault() method which returns 1 if the SOAP::SOM
object is a fault and 0 otherwise.
my $som = $client->someMethod(@parameters);
if ($som->fault) {
print $som->faultdetail;
} else {
# do something
}
PARSING ARRAYS OF ARRAYS
The most efficient way To parse and to extract data out of an array containing another
array encoded in a SOAP::SOM object is the following:
$xml = <<END_XML;
<foo>
<person>
<foo>123</foo>
<foo>456</foo>
</person>
<person>
<foo>789</foo>
<foo>012</foo>
</person>
</foo>
END_XML
my $som = SOAP::Deserializer->deserialize($xml);
my $i = 0;
foreach my $a ($som->dataof("//person/*")) {
$i++;
my $j = 0;
foreach my $b ($som->dataof("//person/[$i]/*")) {
$j++;
# do something
}
}
SEE ALSO
SOAP::Data, SOAP::Serializer
ACKNOWLEDGEMENTS
Special thanks to O'Reilly publishing which has graciously allowed SOAP::Lite to republish
and redistribute large excerpts from Programming Web Services with Perl, mainly the
SOAP::Lite reference found in Appendix B.
COPYRIGHT
Copyright (C) 2000-2004 Paul Kulchenko. All rights reserved.
This library is free software; you can redistribute it and/or modify it under the same
terms as Perl itself.
AUTHORS
Paul Kulchenko (paulclinger@yahoo.com)
Randy J. Ray (rjray@blackperl.com)
Byrne Reese (byrne@majordojo.com)