How to load XML in ACE?

Question

UPDATE 1

Here is how I am currently loading text into my WT project.

wApp->require("ace.js");

//orignal XML, reads in incorrectly on one line
//std::string data = ReadFile("Q:\\settings.xml");

//XML after being formatted in notepad to look like xml, reads in correctly
//std::string data = ReadFile("Q:\\settings.txt");

//changed extension back to XML, edited in notepad++ to XML format, reads in correctly
std::string data = ReadFile("Q:\\settings_from_text.xml");

//test xml tag, reads in correctly
//std::string data = "<tag_1>some tag content</tag_1>";

//test xml tag with newline, reads in incorrectly on one line, doesnt read newline
//std::string data = "<tag_1>some tag content</tag_1>\n<tag_1>some tag content</tag_1>";

_ace_editor = new WText(data, Wt::PlainText);

//_ace_editor->setText(data);
_ace_editor->setInline(false);

// A WContainerWidget is rendered as a div
_ace_editor->resize(1000, 500);

std::string editor_ref = _ace_editor->jsRef(); // is a text string that will be the element when executed in JS

std::string command =
  editor_ref + "._ace_editor = ace.edit(" + editor_ref + ");" +
  editor_ref + "._ace_editor.setTheme(\"ace/theme/chrome\");" +
  editor_ref + "._ace_editor.getSession().setMode(\"ace/mode/xml\");";// +
  //editor_ref + "._ace_editor.setValue(\"" + data + "\");";

_ace_editor->doJavaScript(command);

Also, here is the ReadFile function

std::ifstream in(path, std::ios::in | std::ios::binary);
if(in)
{
  std::string contents;
  in.seekg(0, std::ios::end);
  contents.resize(in.tellg());
  in.seekg(0, std::ios::beg);
  in.read(&contents[0], contents.size());
  in.close();
  return(contents);
}
throw(errno);

ORIGINAL POST

I am trying to load some XML files into an Ace (http://ajaxorg.github.io/ace/#nav=about) editor that I embedded in a WT (http://www.webtoolkit.eu/wt?wtd=rqBfShGlNupXgK3M1sWOxUk1Loz3BsW0) page. The problem is that XML files for whatever reason have all their tags omitted from the load. Example: An XML file with the following content

<?xml version="1.0"?>
<settings>
    <tag_1>some tag content</tag_1>
    <tag_2/>
</settings>

will be loaded as

some tag content

I need the entire XML file as is, not just the contents of the tags.

After doing a bit of research, I have found quite a few other people on different forums asking the same thing but everything I have tried so far has not been working, which brings me here.

This includes setting the Ace mode to XML, trying to load the text in a different container before setting it to the ace window, changing the color schemes, and parsing a file in a different manner.

I am using visual studio 2010, and from debugging I can see that the file does get read in fully into a string with all the tags, but after it is set to the Ace window they are omitted.

astupidname · Answer 1 · 2013-04-22T13:38:16.980

Regardless of whether you are putting it on a WT page or not, bottom line this is a javascript question as that is what the ACE editor is, a javascript tool. Since you have not shown anything at all about how you are loading the xml content, I can only speculate that you must be writing the contents of the xml file into the pages output source?? I'll bet if you view-source do you see the tags? Well if so you are going about it wrong. The xml file needs to be loaded via javascript/ajax as I will demonstrate with a fully working example below (edit the 'url' in the $.ajax call to location of an xml file on your server), which shows tags and all contents of the xml file. Added the jQuery library just for simplicity of the ajax request code. Enjoy!

<!DOCTYPE html>
<html lang="en">
<head>
<title>ACE in Action</title>
<style type="text/css" media="screen">
    #editor { 
        position: absolute;
        top: 0;
        right: 0;
        bottom: 0;
        left: 0;
    }
</style>
</head>
<body>

<div id="editor"></div>

<script src="http://rawgithub.com/ajaxorg/ace-builds/master/src-noconflict/ace.js" type="text/javascript" charset="utf-8"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/2.0.0/jquery.min.js"></script>
<script>
    var callback = function (data, status, xhr) {
        //data will be the xml returned from the server
        if (status == 'success') {
            var editor = ace.edit("editor");
            //apparently, only modes supported are 'html', 'javascript' & 'text'
            editor.getSession().setMode("ace/mode/html");
            editor.setValue(data);
        }
    };
    //using jQuery to fire off an ajax request to load the xml,
    //using our callback as the success function
    $.ajax(
        {
            url : '/testing/cd_catalog.xml',
            dataType : 'text', //explicitly requesting the xml as text, rather than an xml document
            success : callback
        }
    );

</script>
</body>
</html>

Actually, I take back some of what I said about the "must load via javascript/ajax", as I now realize you were just following ACE's example of putting the contents into the editor div beforehand. If you want to do that with html or xml content, the tags will be evaluated by the browser and not show up, unless you copy the editor div's innerHTML then instantiate the editor and then set it's value to the previously saved innerHTML. For example:

<div id="editor"><?xml version="1.0" encoding="ISO-8859-1">
<books>
<text>some text content</text>
<book/>
</books></div>

<script src="http://rawgithub.com/ajaxorg/ace-builds/master/src-noconflict/ace.js" type="text/javascript" charset="utf-8"></script>
<script>
    var txt = document.getElementById('editor').innerHTML;
    var editor = ace.edit("editor");
    //editor.setTheme("ace/theme/monokai");
    editor.getSession().setMode("ace/mode/html");
    editor.setValue(txt);
</script>

This is a bit hard to understand as I am not very fluent in javascript, but from what I can tell you are telling me that the file needs to be loaded using javascript at the time the ace window is created. The problem is that the reason I used ACE and WT is so I would have to mess with javascript as little as possible. I added some more info to the post, I hope it helps show what I am actually doing. On another note, using setValue in javascript set the XML tags properly, but it does not load if there are newline characters present in the file. — user2115945, Apr 24 '13 at 14:19

score 1 · Accepted Answer · answered Apr 24 '13 at 09:09

1

XML fragments in XML... you can somehow expect that your browser will interpret them, unless properly escaped. Try this:

txt = new WText("<bla>something</bla>", Wt::PlainText);

which will escape all XML-ish characters in your text.

Wt's default (XHTMLText) will try to parse your input as XML, and if it succeeds filter possible XSS vectors from the XML before sending it as XML to the browser. If it can't parse the text as XML, it will escape XML-ish characters to avoid that a browser with a liberal parser would unintentionally execute attack vectors.

The third option (XHTMLUnsafeText) bypasses XSS filtering - dangerous, so only use it when you know that your text is safe and can not be influenced directly or indirectly by the user.

answered Apr 24 '13 at 09:09

user52875

3,020
22
21

Well that works to read in the tags, but the XML comes through all on one line. some tag content So it is close, but not quite there. Any ideas on how we can make it read newline characters in XML? Also, I noticed that if I open that XML file in notepad it opens all on one line, same way it shows up in Ace. I made a copy, and formatted like an xml file in notepad using enter for newlines and tab for spacing. Reading in that file was successful and looked like XML. Perhaps the error is in the way the file is saved? Any ideas? – user2115945 Apr 24 '13 at 13:56
Ok, I figured it out. My XML file was saved in UNIX format, instead of windows. Which is what caused it to be loaded on one line. I read it just fine as you suggested, but reading it on one line was a separate issue, which can be seen here http://stackoverflow.com/questions/16201869/why-does-xml-look-differently-in-notepad-and-notepad – user2115945 Apr 25 '13 at 11:33

How to load XML in ACE?

2 Answers2

Linked