add xray.prepare(str, fn) for custom 'title | uppercase' filters

lib/x-ray.js

@@ -3,6 +3,7 @@
  */
 
 var debug = require('debug')('x-ray');
+var assign = require('object-assign');
 var Select = require('x-ray-select');
 var request = require('./request');
 var yieldly = require('yieldly');
@@ -41,6 +42,7 @@ function Xray(url) {
   this._paginate = false;
   this._limit = Infinity;
   this._throws = true;
+  this.prepares = {};
   this.selects = {};
   this.url = url;
   this.keys = [];
@@ -122,6 +124,23 @@ Xray.prototype.format = function(fn) {
   return this;
 };
 
+/**
+ * Prepare
+ */
+
+Xray.prototype.prepare = function(str, fn) {
+  if (!arguments.length) return this.prepares;
+
+  if (1 == arguments.length) {
+    this.prepares = assign(this.prepares, str);
+  } else {
+    this.prepares[str] = fn;
+  }
+
+  return this;
+};
+
+
 
 /**
  * Paginate
@@ -255,6 +274,7 @@ Xray.prototype.traverse = function(fn, done) {
   var get = this.request ? this.request : (this.request = this.use(request()).request);
   var limit = this._paginate ? this._limit : 1;
   var paginate = this._paginate;
+  var prepares = this.prepares;
   var selects = this.selects;
   var throws = this._throws;
   var format = this._format;
@@ -270,7 +290,7 @@ Xray.prototype.traverse = function(fn, done) {
     debug('received response');
 
     var $ = load(body);
-    var select = Select($);
+    var select = Select($, prepares);
     var json = select(selects);
     var href = select(paginate);
 

package.json

@@ -2,7 +2,11 @@
   "name": "x-ray",
   "version": "1.0.2",
   "description": "structure any website",
-  "keywords": ["scraper", "cheerio", "web"],
+  "keywords": [
+    "scraper",
+    "cheerio",
+    "web"
+  ],
   "author": "Matthew Mueller <[email protected]>",
   "repository": {
     "type": "git",
@@ -12,6 +16,7 @@
     "catch-stdout": "0.0.1",
     "cheerio": "^0.17.0",
     "debug": "^2.0.0",
+    "object-assign": "^2.0.0",
     "superagent": "^0.21.0",
     "x-ray-select": "^1.0.3",
     "yieldly": "0.0.1"

test/x-ray.js

@@ -27,6 +27,23 @@ describe('x-ray', function() {
       });
   })
 
+  describe('prepares', function() {
+    it('should support prepares', function(done) {
+      function uppercase(str) {
+        return str.toUpperCase();
+      }
+
+      xray('http://mat.io')
+        .select('title | uppercase')
+        .prepare({ uppercase: uppercase })
+        .run(function(err, str) {
+          if (err) return done(err);
+          assert.equal('MAT.IO', str)
+          done();
+        });
+    })
+  });
+
   it('should support arrays', function(done) {
     xray('http://mat.io')
       .select(['.Header-list-item a'])