Invalid preferences.xml prompt caused by an extension script

[Andrew Noble]

You can just write any id having a slash character. Such as:

<inkscape-extension>
 <_name>myextension</_name>
 <id>python.mysite.com/svg2css</id>

The id is registered to preferences.xml which will cause the prompt on the next Inkscape start.

Related topic in InkscapeForum.com:
<http://www.inkscapeforum.com/viewtopic.php?f=5&t=5910>

[su_v (suv-lp)]

Can you attach your extension files? What platform are you working on, with which Inkscape version?

When testing this type of 'id' (an URL with sub-directory, using a slash) with an existing 'effect' extension (a copy of 'Modify Path > Scatter...' in ~/.config/extensions):

<?xml version="1.0" encoding="UTF-8"?>
<inkscape-extension xmlns="http://www.inkscape.org/namespace/inkscape/extension">
  <_name>Scatter (LeWitt) python.mysite.com/svg2css</_name>
  <id>python.mysite.com/svg2css</id>

Inkscape stores the settings in preferences.xml inside a group like this:

    <group
       svg2css.follow="1"
       svg2css.grouppick="1"
       svg2css.pickmode="rand"
       svg2css.toffset="0"
       svg2css.noffset="0"
       svg2css.space="5"
       id="python.mysite.com"
       svg2css.duplicate="1"
       svg2css.copymode="copy" />
  </group>

Inkscape does launch after a restart without error reading the preferences file and also correctly loads the previously used settings for the extension dialog.
(tested with Inkscape 0.48+devel r9731 on OS X 10.5.8)

[su_v (suv-lp)]

Only reproduced when using a backslash in the id (works with a normal slash).

[su_v (suv-lp)]

Confirmed for using backslashes ('\') as part of the 'ID' string
(tested on OS X, and on Windows, as reported on irc by cm9)

[Craig Marshall (craig9-deactivatedaccount)]

I have tried here on 0.48 and 0.48+devel on Win7, and can't make it crash with a forward slash, but it does mess up the naming of the attributes. For example, if the id was x.y.z/foo, then the id within the group in the preferences.xml get set to just x.y.z, and the attributes of that group are prefixed with "foo.", like the example shown by ~suv above in comment 1.

I can get it to crash by putting either a 1 or 2 backslash characters into the INX id tag, presumably because \ is the escape character within C++ strings and either:

a) A bare \ is valid XML (I'm not sure), and it's not sanitised on reading the XML.
b) A bare \ is not valid XML, and it should be warned about when reading the INX file in.

[su_v (suv-lp)]

Console messages when getting the "The preferences file (...) is not a valid XML document." error:

Entity: line 1442: parser error : Specification mandate value for attribute python.mysite.com
     python.mysite.com\\svg2css.space="10"
                      ^
Entity: line 1442: parser error : attributes construct error
     python.mysite.com\\svg2css.space="10"
                      ^
Entity: line 1442: parser error : Couldn't find end of Start Tag group line 1194
     python.mysite.com\\svg2css.space="10"
                      ^
Entity: line 1442: parser error : Specification mandate value for attribute python.mysite.com
     python.mysite.com\\svg2css.space="10"
                      ^
Entity: line 1442: parser error : attributes construct error
     python.mysite.com\\svg2css.space="10"
                      ^
Entity: line 1442: parser error : Couldn't find end of Start Tag group line 1194
     python.mysite.com\\svg2css.space="10"
                      ^

[su_v (suv-lp)]

Console messages when using a single backslash:

Entity: line 1442: parser error : Specification mandate value for attribute python.mysite.com
     python.mysite.com\svg2css.space="10"
                      ^
Entity: line 1442: parser error : attributes construct error
     python.mysite.com\svg2css.space="10"
                      ^
Entity: line 1442: parser error : Couldn't find end of Start Tag group line 1194
     python.mysite.com\svg2css.space="10"
                      ^
Entity: line 1458: parser error : Opening and ending tag mismatch: inkscape line 2 and group
  </group>
          ^
Entity: line 1459: parser error : Extra content at the end of the document
  <group
  ^

[Andrew Noble (noblestudd)]

Hi All

I think I've hardcoded the forward slash inside preferences.xml.
It does filter the forward slash and inkscape turned it into code below and no error prompt:
  <group
     id="extensions">
    <group
       id="org.ekips.filter"
       hello_world.what="TEST" />
  </group>

But using an unmodified id from the template taken from the MakinAnINX tutorial the { } was not sanitized:
<inkscape-extension>
  <_name>{Friendly Extension Name}</_name>
  <id>{org.domain.sub-domain.extension-name}</id>

That's probably how I got the idea to tinker with preferences.xml directly.
My bad, I should have reported it more properly.