XML::LibXML::Reader

Rails
1

is there anybody who knows how we can get child values using libxml
(Reader class)

def xml_import_to_brands
require’xml’
reader = XML::Reader.file(‘c:/brands.xml’)
.
.
.

2

Quoting lecielbleu [email protected]:

is there anybody who knows how we can get child values using libxml
(Reader class)

def xml_import_to_brands
require’xml’
reader = XML::Reader.file(‘c:/brands.xml’)
.

For docs, go to http://libxml.rubyforge.org/rdoc/index.html, scroll down
in
middle, left windows to LibXML::XML::Reader.

Something along the lines of:

require ‘xml’

stack = []
while reader
case reader.node_type
when XML::Reader::TYPE_ELEMENT
# opening tag
stack << reader.name
stack.pop if reader.empty_element?
when XML::Reader::TYPE_TEXT, XML::Reader::TYPE_CDATA
path = stack.join(‘/’)
case path
when ‘root/parent/child’
puts reader.value # simple content
when ‘root/parent/complex_content’
puts reader.read_inner_xml # contents including markup
when XML::Reader::TYPE_END_ELEMENT
# closing tag
stack.pop
end
end

HTH,
Jeffrey

3

i tried this an get an error =
NoMemoryError
failed to allocate memory
error line number 30 = stack << reader.name

4

Have not seen this error before. Please show more of your code.

Jeffrey

Quoting lecielbleu [email protected]:

5

my xml data seems like that : <Brand_id>2</
Brand_id><Brand_name>HP</Brand_name>
and here is my codes

def xml_testing
require’xml’
reader = XML::Reader.file(‘c:/brands.xml’)

stack = []
while reader
  case reader.node_type
  when XML::Reader::TYPE_ELEMENT
    # opening tag
    stack << reader.name
    stack.pop if reader.empty_element?
  when XML::Reader::TYPE_TEXT, XML::Reader::TYPE_CDATA
    path = stack.join('/')
    case path
    when 'Brands/Brand/Brand_name'
      puts reader.value         # simple content
   when XML::Reader::TYPE_END_ELEMENT
    # closing tag
    stack.pop
  end
end
end

flash.now[:message]="brands read"

end

Note : i add one more “end” cause it was saying unexpected end

6

i guess problem is while reader line because when i run basic code
below :

while doc == true
puts reader.read_string
end

strings never stops in the command line , it turns infinite loop.

7

There are no header tags. I have no idea how libXML will behave.
It
isn’t very tolerant of invalid input. Try adding the puts statements
I’ve
inserted below to find out how far it is getting.

Quoting lecielbleu [email protected]:

while reader
  case reader.node_type
  when XML::Reader::TYPE_ELEMENT
    # opening tag
    stack << reader.name

                puts "BEGIN #{stack.join('/')}"

    stack.pop if reader.empty_element?

                puts "END #{stack.join('/')}"  if

reader.empty_element?

  when XML::Reader::TYPE_TEXT, XML::Reader::TYPE_CDATA
    path = stack.join('/')
    case path
    when 'Brands/Brand/Brand_name'
      puts reader.value         # simple content
   when XML::Reader::TYPE_END_ELEMENT
    # closing tag

                puts "END #{stack.join('/')}"
8

i tried also
while doc == true
while doc = 1
while doc

results dont change…

9

I’m afraid I don’t understand what you are trying to do here. ‘doc’
isn’t in
the example below. So how the loop would change its value, I am
unclear. It
seems like you are saying a loop with an unchanging condition runs
forever.
Yes, it does.

Did you intend to do this:

while reader.read
puts reader.read_string
end

HTH
Jeff

Quoting lecielbleu [email protected]:

10

Glad it is working.

Jeff

Quoting lecielbleu [email protected]:

11

ok Jeff i solved problem , using “doc” was a bad mistake :slight_smile: thanks for
your support ,here is the last codes

while reader.read
  case reader.name
    when "Brand_name"
    name_from_xml = reader.read_string
    Brand.create( :name => name_from_xml )
  end
end

now i have to solve another problem :slight_smile: do you know how can i get a
brand_name using filter brand_id

while reader.read
  case reader.read_string
    when 55
                           -------magic line i couldnt find :)

  end
end

magic line must be get brand_name value “Dell” using “55”

Sample xml code ===>> <Brand_id>55</Brand_id><Brand_name>Dell</
Brand_name>