oidc-lib/src/client_shims/handlebars.js

A library for creating OIDC Service Providers

module.exports = {
   compile: compile
}

function compile(source){
   var offset = 0;
   var segments = [];
   while (offset < source.length){
   	var startTokenOffset = source.substring(offset).indexOf('{{#');
   	if (startTokenOffset >=0 ){
         startTokenOffset += offset;
         segments.push({source: [], content: source.substring(offset, startTokenOffset)});
      	endOfStartTokenOffset = startTokenOffset + 3;
         var tokenLength = source.substring(endOfStartTokenOffset).indexOf('}}');
         var tokenName = source.substring(endOfStartTokenOffset, endOfStartTokenOffset + tokenLength);
         var endOfStartToken = startTokenOffset + tokenName.length + 6; 
         var closingToken = '{{/' + tokenName + '}}';
         var closingTokenOffset = source.substring(endOfStartToken).indexOf(closingToken);
         var tokenContent = source.substring(endOfStartToken, endOfStartToken + closingTokenOffset);
         var endTokenOffset = endOfStartToken + tokenContent.length + closingToken.length;
         segments.push({source: [tokenName], content: tokenContent});
      }
      else{
         segments.push({source: [], content: source.substring(offset, source.length)});
         var endTokenOffset = source.length;
      }

      offset = endTokenOffset;
   }

   addTemplateFunction(segments);

   return templateProcessor;
}

function substitute(tokenContent, json){
   for (var claim in json){
      tokenContent = tokenContent.replace(new RegExp('{{{' + claim + '}}}', 'g'), json[claim]).replace(new RegExp('{{' + claim + '}}', 'g'), json[claim]);
   }

   return tokenContent;
}

function addTemplateFunction(segments){
   var oScript = document.createElement('script');
   oScript.language = 'javascript';
   oScript.type = 'text/javascript';
   oScript.text = templateProcessorSource.toString()
      .replace('templateProcessorSource', 'templateProcessor')
      .replace('// placeHolderForSegments', 'var segments = ' + JSON.stringify(segments) + ';') 
      + '\r\n\r\n' + templateProcessorSubstitute.toString();
   document.getElementsByTagName('BODY').item(0).appendChild(oScript);
}

function templateProcessorSource(context){
   // placeHolderForSegments
   var output = "";
   for (var c1=0; c1 < segments.length; c1++){
      var step =segments[c1];
      if (step.source.length === 0){
         output += step.content;
      }
      else if (step.source.length === 1){
         var repeater = context[step.source[0]];
         for (var c2=0; c2 < repeater.length; c2++){
            output += templateProcessorSubstitute(step.content, repeater[c2]);            
         }
      }
   }

   output = templateProcessorSubstitute(output, context);

   return output;
}

function templateProcessorSubstitute(tokenContent, json){
   for (var claim in json){
      var tokenContent = tokenContent.replace(new RegExp('{{{' + claim + '}}}', 'g'), json[claim]).replace(new RegExp('{{' + claim + '}}', 'g'), json[claim]);
   }

   return tokenContent;
}