beginning of pagination api

core/shared/models/dataProvider.bookshelf.base.js

@@ -24,6 +24,7 @@
      * @param opts (optional)
      */
     BookshelfBase.prototype.findAll = BookshelfBase.prototype.browse = function (opts) {
+        opts = opts || {};
         return this.collection.forge().fetch(opts);
     };
 

core/shared/models/dataProvider.bookshelf.posts.js

@@ -1,8 +1,10 @@
 (function() {
     "use strict";
 
-    var util = require('util'),
+    var _ = require('underscore'),
+        util = require('util'),
         models = require('./models'),
+        Bookshelf = require('./bookshelf'),
         BaseProvider = require('./dataProvider.bookshelf.base'),
         PostsProvider;
 
@@ -13,6 +15,70 @@
         BaseProvider.call(this, models.Post, models.Posts);
     };
 
+    /**
+     * Find results by page - returns an object containing the
+     * information about the request (page, limit), along with the
+     * info needed for pagination (pages, total).
+     *
+     * {
+     *   posts: [
+     *    {...}, {...}, {...}
+     *   ],
+     *   page: __,
+     *   limit: __,
+     *   pages: __,
+     *   total: __
+     * }
+     *
+     * @params opts
+     */
+    PostsProvider.prototype.findPage = function (opts) {
+        var postCollection;
+        opts = _.defaults(opts || {}, {
+            page: 1,
+            limit: 15,
+            where: null
+        });
+        postCollection = this.collection.forge();
+
+        // If there are where conditionals specified, add those
+        // to the query.
+        if (opts.where) {
+            postCollection.query('where', opts.where);
+        }
+
+        // Set the limit & offset for the query, fetching
+        // with the opts (to specify any eager relations, etc.)
+        // Omitting the `page`, `limit`, `where` just to be sure
+        // aren't used for other purposes.
+        return postCollection
+            .query('limit', opts.limit)
+            .query('offset', opts.limit * (opts.page - 1))
+            .fetch(_.omit(opts, 'page', 'limit', 'where'))
+            .then(function (collection) {
+                var qb;
+
+                // After we're done, we need to figure out what
+                // the limits are for the pagination values.
+                qb = Bookshelf.Knex(_.result(collection, 'tableName'));
+
+                if (opts.where) {
+                    qb.where(opts.where);
+                }
+
+                return qb.count(_.result(collection, 'idAttribute')).then(function (resp) {
+                    var totalPosts = resp.aggregate;
+                    return {
+                        posts: collection.toJSON(),
+                        page: opts.page,
+                        limit: opts.limit,
+                        pages: Math.ceil(totalPosts / opts.limit),
+                        total: totalPosts
+                    };
+                });
+            });
+    };
+
     util.inherits(PostsProvider, BaseProvider);
 
     module.exports = PostsProvider;