Table bug fix and wrap sql only when needed

Conditionally wrap sql into subqueries if its not already. Drop default
sql table support

lib/server.js

@@ -86,8 +86,8 @@ module.exports = function(opts){
 			function preTileRender(err) {
 				if (err) throw err;
 
+				if(!req.params.sql) throw new Error("SQL is required after parameter parsing");		
 				if(!req.params.style) delete req.params.style
-				if(!req.params.sql) delete req.params.sql				
 
                 _.defaults(req.params, app.getDefaults(req.params));
 
@@ -169,14 +169,23 @@ module.exports = function(opts){
 
         layers.forEach(function(layer, i){
             params.ids.push(layer.id);
-            params.sql.push("("+layer.sql+") as " + layer.id + "_subquery");
+            params.sql.push(app.wrapSql(layer.sql, layer.id));
             params.style.push(layer.style);
             params.interactivity.push(layer.interactivity);
             if(typeof params.layer === 'undefined' && layer.interactivity) { // The first valid interactivity is the layer
                 params.layer = i;
             }
         });
     }
+
+	app.wrapSql = function(sql, layerId) {
+		var preWrapped = /\(.*?\)\s+(as )?\w+$/.test(sql)
+		if(!preWrapped) {
+			sql = "("+sql+") as " + layerId + "_subquery";
+		}
+
+		return sql;
+	}
 
 	app.getDefaults = function(params) {
 		var params = params || {};
@@ -191,15 +200,11 @@ module.exports = function(opts){
 			'#<%= id %>[mapnik-geometry-type=1] ' + def_style_point +		
 			'#<%= id %>[mapnik-geometry-type=2] ' + def_style_line +		
 			'#<%= id %>[mapnik-geometry-type=3] ' + def_style_poly);
-
-        // If table parameter exists, use it as default sql
-		var default_sql = _.template("SELECT * FROM <%= table %>");
 
 		return {
 			dbtype: options[params.mapKey].dbtype,
 			id: params.id,
 			style: default_style(params),
-			sql: default_sql(params),
 			format: 'png',
 			geom_type: 'polygon',
 			interactivity: null

package.json

@@ -1,6 +1,6 @@
 {
   "name": "windwalker",
-  "version": "0.1.1",
+  "version": "0.1.2",
   "main": "./lib/index.js",
   "description": "A Node.js based map tile server using Mapnik",
   "url": "https://github.com/BHare1985/Windwalker",

test/support/server_options.js

@@ -16,9 +16,12 @@ module.exports = function(opts) {
             // no default interactivity. to enable specify the database column you'd like to interact with
             req.params.interactivity = null;
 
+            req.params.sql = "SELECT * FROM "+req.params.table;
+
             // this is in case you want to test sql parameters eg ...png?sql=select * from my_table limit 10
             req.params =  _.extend({}, req.params);
             _.extend(req.params, req.query);
+
 
             // send the finished req object on
             callback(null,req);