Re: [gobo-eiffel-develop] Gobo example for reading attributes in XML?

[Neal L. <ne...@3d...>]

At 02:13 PM 11/18/2007, Eric Bezault wrote:
>Bru...@ao... wrote:
> > Eric:
> >
> > I am looking to read and XML file with Eiffel and it seems that your
> > Gobo classes can do this.  I looked at the examples for Gobo and I don't
> > see any example that actually read AND USE an XML file.
> >
> > Can you point me to any example that show how to use Gobo to read the
> > attributes of an XML file?  Ideally, it would include the input XML file
> > as well.


Hi Bruce,

The two approaches I've used are:

1) Create a descendent of XM_CALLBACKS and process the attributes as 
the parser sends them to your class.  An example of this approach may 
be found at

http://swete.svn.sourceforge.net/viewvc/swete/trunk/swete/test/swete_script_callbacks.e?view=markup

2) Use XM_TREE_CALLBACKS_PIPE to create the xml tree in memory and 
then obtain the information you are looking for from that tree.  For example:


         update_virtual_domain_hosts: BOOLEAN is
                         -- Update table containing all virtual 
domain hosts from file
                         -- Returns true if table was updated
                         -- false if there was a problem reading the 
file and the hash table was not updated
                 local
                         temp_virtual_domain_hosts: DS_HASH_TABLE 
[VIRTUAL_DOMAIN_HOST, STRING]
                         file: KL_TEXT_INPUT_FILE
                         hosts: DS_LIST [XM_ELEMENT]
                         aliases: DS_LIST [XM_ELEMENT]
                         new_host: VIRTUAL_DOMAIN_HOST
                         host_element: XM_ELEMENT
                         read_exception: BOOLEAN
                 do
                         if not read_exception then
                                 create temp_virtual_domain_hosts.make (15)
                                 create host_parser.make
                                 create callbacks.make
                                 host_parser.set_callbacks (callbacks.start)
                                 create file.make 
(configuration.virtual_hosts_file_name)
                                 file.open_read
                                 host_parser.parse_from_stream (file)
                                 hosts := 
callbacks.tree.document.root_element.elements
                                 from
                                         hosts.start
                                 until
                                         hosts.after
                                 loop
                                         host_element := hosts.item 
(hosts.index)
                                         create new_host
                                         new_host.set_host_name 
(host_element.attribute_by_name ("virtual_host_name").value)
                                         new_host.set_company 
(host_element.attribute_by_name ("company").value)
                                         new_host.set_company_abbreviation 
(host_element.attribute_by_name ("company_abbreviation").value)
                                         new_host.set_banner_text 
(host_element.attribute_by_name ("banner_text").value)
                                         new_host.set_url 
(host_element.attribute_by_name ("url").value)
                                         new_host.set_style_sheet 
(host_element.attribute_by_name ("style_sheet").value)
                                         new_host.set_logo 
(host_element.attribute_by_name ("logo").value)
                                         new_host.set_logo_width 
(host_element.attribute_by_name ("logo_width").value.to_integer)
                                         new_host.set_logo_height 
(host_element.attribute_by_name ("logo_height").value.to_integer)
                                         new_host.set_default_state 
(host_element.attribute_by_name ("default_state").value)
                                         new_host.set_required_fields_color 
(host_element.attribute_by_name ("required_fields_color").value)
-- 
new_host.set_program_ready_message (host_element.attribute_by_name 
("program_ready_message").value)
                                         new_host.set_faq_price_answer 
(host_element.attribute_by_name ("faq_price_answer").value)
                                         new_host.set_price 
(host_element.attribute_by_name ("price").value.to_integer)
                                         if equal 
(host_element.attribute_by_name ("use_ssl").value.as_upper, "YES") then
                                                 new_host.set_use_ssl
                                         end
--                                      if equal 
(host_element.attribute_by_name 
("show_requirement_at_greeting").value.as_upper, "YES") then
-- 
new_host.set_show_requirement_at_greeting
--                                      end
                                         aliases := 
host_element.element_by_name ("aliases").elements
                                         from
                                                 aliases.start
                                         until
                                                 aliases.after
                                         loop
                                                 temp_virtual_domain_hosts.force_last 
(new_host, aliases.item (aliases.index).text)
                                                 aliases.forth
                                         end
                                         hosts.forth
                                 end
                                 virtual_domain_hosts.copy 
(temp_virtual_domain_hosts)
                                 file.close
                         end
                         Result := not read_exception
                 rescue
                         read_exception := True
                         retry
                 end

         host_parser: XM_EIFFEL_PARSER

         callbacks: XM_TREE_CALLBACKS_PIPE

Here is the associated XML:

   <?xml version="1.0" encoding="UTF-8" ?>
- <host_list xmlns="http://www.freesafetyprogram.com/hosts">
- <!--


Virtual Domain Host Content
Author:         Neal L Lester [nea...@3d...]
date:           $Date: 2005/03/07 14:45:35 $
revision:       $Revision: 1.3.2.3 $
copyright:      (c) Neal L Lester


   --> - <host virtual_host_name="www.mysafetyprogram.com" 
company="mysafetyprogram.com" company_abbreviation="MSP" 
banner_text="Click here for Bay Area safety consulting services" 
url="http://www.mysafetyprogram.com/resume.htm" style_sheet="fsp.css" 
logo="ff_hepa.gif" logo_width="56" logo_height="80" 
default_state="CA" required_fields_color="Green" 
faq_price_answer="Viewing the final created program costs $249. You 
may view, print, and modify the program (without limitation) for up 
to one year at no additional cost." price="249" use_ssl="yes">
- <aliases>
   <alias>www.mysafetyprogram.com</alias>
   <alias>mysafetyprogram.com</alias>
   <alias>www.freesafetyprogram.com</alias>
   <alias>freesafetyprogram.com</alias>
   <alias>default</alias>
   </aliases>
   </host>
   </host_list>


Neal