WriteXML generating incorrect file

Original Reporter info from Mantis: dgaspary @dgaspary

• Reporter name: Daniel Gaspary

Description:

The Attached Program was created to generate the following XML:

<svg xmlns="http://www.w3.org/2000/svg"
     xmlns:xlink="http://www.w3.org/1999/xlink">
  <script xlink:href="cool-script.js" type="text/ecmascript"/>
</svg>

The program finishes without problems. But the generated file misses the "xmlns:xlink=..." attribute and this causes an error when trying to open the file with Firefox or another browser.

On Other hand, an Execution error is raised if the line 20 is uncommented (setAttributeNS) and the lines 21, 22 and 23 are commented.

Mantis conversion info:

• Mantis ID: 22299
• OS: Linux
• OS Build: Ubuntu 11.04
• Build: 2012/02/12
• Platform: x86-64
• Version: 2.6.1

added CategoryFCL Version2.6.1 labels

Converted from Mantis. Note by Sergei Gorelkin

• Mantis submitter username: Gorelkin
• Mantis submitter real name: Sergei Gorelkin

---

You are creating ScriptNode using CreateElement method, which creates an element without namespace. The specification says that such documents must fail to serialize (however it doesn't say anything about behavior of DOM). The only bug in fcl-xml is that this isn't properly checked.

Using CreateElementNS yields the necessary result:

ScriptNode:=XMLDoc.CreateElementNS('http://www.w3.org/2000/svg','script');

but the 'xmlns:xlink' attribute appears on the 'script' element. If you want it to appear on 'svg', you should set it there.

Also I couldn't reproduce the runtime error with 2.7.1.

Converted from Mantis. Note by Daniel Gaspary @dgaspary

• Mantis submitter username: dgaspary @dgaspary
• Mantis submitter real name: Daniel Gaspary

---

"Using CreateElementNS yields the necessary result"

True, the Specification says to avoid mix NS and not NS aware methods.

"but the 'xmlns:xlink' attribute appears on the 'script' element. If you want it to appear on 'svg', you should set it there."

Ok, but is possible to create the below file with fcl-xml?

<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" >
  <script1 xlink:href="cool-script.js"/>
  <script2 xlink:href="cool-script.js"/>
  <script3 xlink:href="cool-script.js"/>
</svg>

The attached project2.lpr instead create:

<svg xmlns="http://www.w3.org/2000/svg">
  <script1 xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cool-script.js"/>
  <script2 xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cool-script.js"/>
  <script3 xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cool-script.js"/>
</svg>

Both are valid XML files, but the First is a much more compact form.

At The specification[1] you can find:

"As far as the DOM is concerned, special attributes used for declaring XML namespaces are still exposed and can be manipulated just like any other attribute."

Is this true to fcl-xml ? I have tried and was not possible find the declarative nodes(example: xmlns:xlink="http...") using GetAtrribute/GetAtrributeNS.

Examinating the DOM code, it seems to just store references to nsPrefix and nsURI, it doesnt really create attribute nodes. So is not possible to move the attribute xmlns:xlink="http://www.w3.org/1999/xlink" to the svg node.

[1] http://www.w3.org/TR/2000/REC-DOM-Level-2-Core-20001113/core.html#Namespaces-Considerations

Converted from Mantis. Note by Daniel Gaspary @dgaspary

• Mantis submitter username: dgaspary @dgaspary
• Mantis submitter real name: Daniel Gaspary

---

The ReadXmlWithNamespaces.pas shows that the TDOMParser class when is reading a "compact" XML (as mentioned at the prior comment) with namespaces actually create attributes nodes contrary to dom behaviour.

Converted from Mantis. Note by Sergei Gorelkin

• Mantis submitter username: Gorelkin
• Mantis submitter real name: Sergei Gorelkin

---

You should explicitly attach an 'xmlns:xlink' attribute to the 'svg' element:

 XmlDoc := TXMLDocument.Create;
 SvgNode:=XMLDoc.CreateElementNS('http://www.w3.org/2000/svg', 'svg');
 SvgNode.SetAttributeNS('http://www.w3.org/2000/xmlns/','xmlns:xlink','http://www.w3.org/1999/xlink');  //<--here

 XMLDoc.AppendChild(SvgNode);
 ScriptNode:=XMLDoc.CreateElementNS('http://www.w3.org/2000/svg','script');
 ScriptNode.SetAttributeNS('http://www.w3.org/1999/xlink', 'xlink:href', 'cool-script.js');

DOM doesn't create additional attributes automatically, the namespace fixup only happens when writing the document out (it is rather complex process which may also change prefixes of attributes in case of conflicting namespaces).

Converted from Mantis. Note by Daniel Gaspary @dgaspary

• Mantis submitter username: dgaspary @dgaspary
• Mantis submitter real name: Daniel Gaspary

---

"SvgNode.SetAttributeNS('http://www.w3.org/2000/xmlns/','xmlns:xlink','http://www.w3.org/1999/xlink'); [^] //<--here"

I never would guess that solution.

Thank you, Sergei.

Converted from Mantis. Note by Daniel Gaspary @dgaspary

• Mantis submitter username: dgaspary @dgaspary
• Mantis submitter real name: Daniel Gaspary

---

This issue can be closed.

Converted from Mantis. Note by Sergei Gorelkin

• Mantis submitter username: Gorelkin
• Mantis submitter real name: Sergei Gorelkin

---

I keep it open because I want to add the check for non-namespaced elements during serialization. It is trivial but requires extensive testing for possible side effects.

Attached files:

• ReadXmlWithNamespaces.pas (Size: 971 bytes, user: (), date: 2012-06-22)
• compact.xml (Size: 254 bytes, user: (), date: 2012-06-22)
• project2.lpr (Size: 707 bytes, user: (), date: 2012-06-22)
• project1.lpr (Size: 773 bytes, user: (), date: 2012-06-22)

mentioned in issue #25183 (closed)

marked this issue as related to #25183 (closed)

added XML label