W3C home > Mailing lists > Public > public-xml-processing-model-comments@w3.org > October 2007

Re: An unfulfilled requirement maybe?

From: Norman Walsh <ndw@nwalsh.com>
Date: Fri, 05 Oct 2007 13:59:16 -0400
To: public-xml-processing-model-comments@w3.org
Message-ID: <m2d4vtfnnv.fsf@nwalsh.com>
Here's a proposal for p:exec: (Let's argue about whether "exec" is an
abbreviatio or not some other time :-)

  <p:declare-step type="p:exec">
    <p:input port="source" primary="true" sequence="true"/>
    <p:output port="result" primary="true"/>
    <p:output port="errors"/>
    <p:option name="command" required="true"/>
    <p:option name="args"/>
    <p:option name="cwd"/>
    <p:option name="source-is-xml" value="true"/>
    <p:option name="result-is-xml" value="true"/>
    <p:option name="errors-is-xml" value="false"/>
    <p:option name="fix-slashes" value="false"/>

    <!-- plus the serialization options -->
    <p:option name="byte-order-mark"/>
    <p:option name="cdata-section-elements"/>
    <p:option name="doctype-public"/>
    <p:option name="doctype-system"/>
    <p:option name="encoding"/>
    <p:option name="escape-uri-attributes"/>
    <p:option name="include-content-type"/>
    <p:option name="indent" value="false"/>
    <p:option name="media-type"/>
    <p:option name="method" value="xml"/>
    <p:option name="normalization-form"/>
    <p:option name="omit-xml-declaration"/>
    <p:option name="standalone"/>
    <p:option name="undeclare-prefixes"/>
    <p:option name="version" value="1.0"/>
  </p:declare-step>  

Executes $command with $args, feeding "source" to stdin and reading
"result" from stdout and "errors" from stderr.

Any "/" or "\" in the $command are transformed into the
platform-specific path separator character.

If $cwd is specified, then the current working directory is changed to
$cwd before execution begins. It is a dynamic error if that's not
possible. If $cwd is not specified, the current working directory is
implementation-defined.

$args is interpreted as a sequence of whitespace-separated values.
Single or double quotes may be used to group arguments containing
whitespace. A \" or \' is taken as a literal quote character. A
backslash is \\.

For example:

  <p:option name="args" value='a b c "c d e" \"f g\" &apos;g h&apos;'/>

Sets the arguments to (using square brackets as a visal delimeter):

  [a] [b] [c] [c d e] ["f] [g"] [g h]

if $fix-slashes is true, all "/" or "\" in $args are transformed into
the platform-specific path separator character.

If $source-is-xml is true, then the serialization options are used to
convert each of the inputs into serialized XML and they're written to
the commands stdin.

If $source-is-xml is false, the XPath 1.0 string-value of the document
node of each of the inputs is written to stdin.

If $result-is-xml/errors-is-xml is true, then the result is parsed with
namespaces turned on, validation turned off, and no further
processling (like p:document).

If $result-is-xml/errors-is-xml is false, then the result is a c:result
element containing the escaped output.

I think that covers it. Argument processing sort of sucks. I wonder
if we need to worry about setting environment variables.

I think if we need something more complicated, we'll end up going the
route of http-request :-)

                                        Be seeing you,
                                          norm

-- 
Norman Walsh <ndw@nwalsh.com> | Everything should be made as simple as
http://nwalsh.com/            | possible, but no simpler.

Received on Friday, 5 October 2007 17:59:30 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 8 January 2008 14:21:42 GMT