Rails Throws "rexml::parseexception Does Not Have A Valid Root" Exception

I have a JavaScript object, and converted it into JSON using Douglas Crockford's JSON utility. While sending a post AJAX request, I get: REXML::ParseException does not have a val

Solution 1:

When making your AJAX request, you're probably sending the wrong Content-Type header. If you make a request with the header Content-Type: application/xml, Rails will try to parse your request body as XML, and you'll get that error message. Instead, you'll want to use application/json or another content-type so that Rails won't try to parse it. If you're using jQuery, this is the contentType setting in $.ajax.

Solution 2:

JSON doesn't require there to be a root element the way XML does. Try parsing it with JSON.parse(json_string), instead of with REXML.

Solution 3:

See the below mentioned json file

{"glossary":{"title":"example glossary","GlossDiv":{"title":"S","GlossList":{"GlossEntry":{"ID":"SGML","SortAs":"SGML","GlossTerm":"Standard Generalized Markup Language","Acronym":"SGML","Abbrev":"ISO 8879:1986","GlossDef":{"para":"A meta-markup language, used to create markup languages such as DocBook.","GlossSeeAlso":["GML","XML"]},"GlossSee":"markup"}}}}}

Here glossary is the root element which encloses the whole json similarly to xml as displayed below.

<!DOCTYPE glossaryPUBLIC"-//OASIS//DTD DocBook V3.1//EN"><glossary><title>example glossary</title><GlossDiv><title>S</title><GlossList><GlossEntryID="SGML"SortAs="SGML"><GlossTerm>Standard Generalized Markup Language</GlossTerm><Acronym>SGML</Acronym><Abbrev>ISO 8879:1986</Abbrev><GlossDef><para>A meta-markup language, used to create markup
languages such as DocBook.</para><GlossSeeAlsoOtherTerm="GML"><GlossSeeAlsoOtherTerm="XML"></GlossDef><GlossSeeOtherTerm="markup"></GlossEntry></GlossList></GlossDiv></glossary>

Hence we can say that the glossary is the root and is only one tag in xml or json.

Hence you have to provide a root element in the json file which encloses the whole JSON file.