track preprocessor exceptions

Author: takempf

lib/preprocessor.js

@@ -21,6 +21,7 @@ var Preprocessor = function( preprocessor_path, options ){
 
 	var server = options.server;
 	var logger = server.logger;
+	var raven_client = server.raven_client;
 	var preprocessor = this;
 	var data = this.data = '{}';
 	this.path = preprocessor_path;
@@ -29,8 +30,15 @@ var Preprocessor = function( preprocessor_path, options ){
 	this.process = function( context, callback ){
 
 		workers( context, this.path, function( err, preprocessed_context ){
-			if( err ){ 
+			// preprocessor errors don't bubble up
+			// so log them here
+			if( err ){
 				logger.log( 'Preprocessor Error:\n'+ err.stack, 0 );
+				raven_client.captureError( err, {
+					extra: {
+						context: context
+					}
+				});
 				if( callback ) return callback( context );
 			}
 			if( callback ) return callback( preprocessed_context );