topic Re: XML Attribute Namespace, Lookup Tables in Talend Studio

XML Attribute Namespace, Lookup Tables

Anonymous — Sat, 16 Nov 2024 12:30:50 GMT

Hi,
(1) I'm trying to generate:
<Host xlink:type="simple" xlink:href="#SomeElement1"/>
I'm not able to set namespaces for attributes such as xlink:type in the above example.
(2) Next I need to populate the values for xlink:href to some other xml elements within the document.
What would be possible ways to achieve this?
(a) One way would be to have a Map/LookupTable which I can query to retrieve the right element I need to link to, with which I can populate xlink:href.
How do I do this?

Re: XML Attribute Namespace, Lookup Tables

Anonymous — Wed, 14 Dec 2011 04:02:45 GMT

<Host
  xmlns:my="http://example.com/"
  xmlns:xlink="http://www.w3.org/1999/xlink"
  xlink:type="simple"
  xlink:href="#SomeElement1"
  />

Could you show me more details, input files and results you want?
I can't catch your point now.
Best regards!
Pedro

Re: XML Attribute Namespace, Lookup Tables

Anonymous — Wed, 14 Dec 2011 07:43:03 GMT

Hi!
Thanks Pedro.
Basically my output is of the following format:
<root xmlns:xlink="http://www.w3.org/1999/xlink">
<SomeElement1 id="1" >
<Host xlink:type="simple" xlink:href="nil"/>
...
</SomeElement1>
<SomeElement2 id="2">
<Host xlink:type="simple" xlink:href="#1"/>
...
</SomeElement2>
<SomeElement3 id="3">
<Host xlink:type="simple" xlink:href="#2"/>
...
</SomeElement3>
</root>
Case 1:
I'm using tAdvancedFileOutputXML, my input is an interfaceRegEx.
In the "Configure XML Tree option", I added xlink namespace on the root element.
However there was no way to "specify" a namespace for the attribute "type" in the element "Host".
So i just clicked on add attribute and typed "xlink:type".
My point here is Talend does not intelligently allow me to add a namespace to an attribute. This is however not a problem yet.
Case 2:
In the above XML snippet, you can see that each element is referencing some other element using xlink
SomeElement1 with id="1" is referencing nil.
SomeElement2 with id="2" is referencing SomeElement1 (xlink:href="#1")
SomeElement3 with id="3" is referencing SomeElement3
Now the information of which element references any other element should be stored in a map like this:
key Value
SomeElement1 nil
SomeElement2 #1
SomeElement3 #2
Next in my XML Output, as you can see above, as per the values in the map, I want to populate the xlink:href attribute of the host element.
Example:
when generating
<SomeElement2 id="2">, it should check the map and retrieve the value #1, and then this value should be populated in the href attribute of its host subelement.
Which component do I use to populate/create a map?
How do I query the map to fill up the values of the href attribute.
Hope I made things clear, and my question is probably very preliminary, in that case only provide the components and approach, I'll try working with it

Re: XML Attribute Namespace, Lookup Tables

Anonymous — Wed, 14 Dec 2011 10:16:47 GMT

Hi
I feel impossible to retrieve the value from 'SomeElement' dynamically.
But you may use a lookup input file, set the data as follows.
Then join two input flows with tMap.

nil
#1
#2
#3
...

Still i feel a little confused why you use a tFileInputRegex here and the detail of your input data.
Welcome to Talend Community.
Best regards!
Pedro

Re: XML Attribute Namespace, Lookup Tables

Anonymous — Wed, 14 Dec 2011 10:53:03 GMT

Sorry if I have confused you.
Let me make it clear.
Input: A flat file which I'm using RegEx to extract data (details not required)
Output: XML file.
The output is the XML file, I'm not trying to "retrieve the value from 'SomeElement' dynamically."
(1) Given Input from any file, I want to create a map as shown above.
(2) From the map I want to populate the href field of the xml.

Re: XML Attribute Namespace, Lookup Tables

Anonymous — Thu, 15 Dec 2011 07:58:32 GMT

Hi
For case 1, you can right click on the Attribute 'xmlns:link', choose 'Set A Fixed Value' and type ' http://www.w3.org/1999/xlink'.
For case 2, I can come up with one way. Create a lookup table as follows.

id     href
1      nil
2      #1
3      #2
4      #3
5      #4
...

Then use component tMap to join your input file and this lookup file.
You may find more details in the following images.
Best regards!
Pedro