Merge pull request #34 from jrtechs/NextPage

Next page implementation

includes/html/header.html

@@ -8,8 +8,8 @@
 
     <meta name="viewport" content="width=device-width, initial-scale=1">
 
-    <link rel="stylesheet" href="/includes/css/purge.css" media="screen">
-    <!--<link rel="stylesheet" href="/css/bootstrap.css" media="screen">-->
+    <!--<link rel="stylesheet" href="/includes/css/purge.css" media="screen">-->
+    <link rel="stylesheet" href="/includes/css/bootstrap.css" media="screen">
     <link rel="stylesheet" href="/includes/css/code.css" media="screen">
 
 

includes/includes.js

@@ -50,9 +50,9 @@ const sendCachedContent = function(path, type, result)
                     'Vary': 'Accept-Encoding'});
             result.write(content);
             result.end();
-            cache.put(path, content);
         }).catch(function(error)
         {
+            cache.del(path);
             console.log(error);
         });
     }

includes/staticContentServer.js

@@ -35,8 +35,11 @@ module.exports=
             //scripts
             else if (filename.includes(".js"))
             {
-                includes.sendJS(result, baseURL + filename);
-                return true;
+                if(baseURL.includes("includes/") || baseURL.includes("blogContent"))
+                {
+                    includes.sendJS(result, baseURL + filename);
+                    return true;
+                }
             }
             //html
             else if (filename.includes(".html"))

posts/category.js

@@ -1,9 +1,8 @@
-//DB query
+/** DB query */
 const sql = require('../utils/sql');
 
-//file IO
-const utils = require('../utils/utils.js');
-
+/** Object used to render blog post previews */
+const batchPreview = require('../posts/renderBatchOfPreviewes');
 
 /**
  * Renders all posts in a single category
@@ -11,7 +10,7 @@ const utils = require('../utils/utils.js');
  * @param resultURL
  * @returns {*}
  */
-const renderPosts = function(resultURL)
+const renderPosts = function(resultURL, page)
 {
     const splitURL = resultURL.split("/");
     if(splitURL.length >= 3)
@@ -20,38 +19,16 @@ const renderPosts = function(resultURL)
         {
             sql.getPostsFromCategory(splitURL[2]).then(function(posts)
             {
-                var promises = [];
-                posts.forEach(function(p)
-                {
-                    promises.push(new Promise(function(res, rej)
-                    {
-                        require("../posts/singlePost.js")
-                            .renderPreview(p).then(function(html)
-                        {
-                            res(html);
-                        }).catch(function(error)
-                        {
-                            rej(error);
-                        })
-                    }));
-                });
-
-                Promise.all(promises).then(function(content)
-                {
-                    resolve("<div class='col-md-8'>" + content.join('') + "</div>");
-                }).catch(function(error)
-                {
-                    reject(error);
-                });
-            }).catch(function(err)
+                resolve(batchPreview.main(resultURL, posts, page, 5));
+            }).catch(function(error)
             {
-                reject(err);
+                reject(error);
             })
         });
     }
     else
     {
-        return utils.print404();
+        reject("Page Not Found");
     }
 };
 
@@ -60,14 +37,16 @@ module.exports=
         /**
          * Calls posts and sidebar modules to render blog contents in order
          *
-         * @param res
-         * @param fileName request url
+         * @param requestURL
+         * @param request
+         * @returns {Promise}
          */
         main: function(requestURL, request)
         {
             return new Promise(function(resolve, reject)
             {
-                Promise.all([renderPosts(requestURL),
+                var page = request.query.page;
+                Promise.all([renderPosts(requestURL, page),
                     require("../sidebar/sidebar.js").main()]).then(function(content)
                 {
                     resolve(content.join(''));

posts/homePage.js

@@ -1,42 +1,19 @@
 const sql = require('../utils/sql');
 
-const postRenderer = require('../posts/singlePost.js');
+const batchPreview = require('../posts/renderBatchOfPreviewes');
 
 /**Renders each recent post for the homepage of the website
  *
  * @param result
  * @returns {*|Promise}
  */
-var renderRecentPosts = function()
+var renderRecentPosts = function(baseURL, page)
 {
     return new Promise(function(resolve, reject)
     {
         sql.getRecentPostSQL().then(function(posts)
         {
-            var postPromises = [];
-            var content = "<div class='col-md-8'>";
-            posts.forEach(function(post)
-            {
-                postPromises.push(new Promise(function(res, rej)
-                {
-                    postRenderer.renderPreview(post).then(function(cont)
-                    {
-                        res(cont);
-                    }).catch(function(error)
-                    {
-                        rej(error);
-                    })
-                }));
-            });
-
-            Promise.all(postPromises).then(function(cont)
-            {
-                content = content + cont.join('') + "</div>";
-                resolve(content);
-            }).catch(function(error)
-            {
-                reject(error);
-            })
+            resolve(batchPreview.main(baseURL, posts, page, 5));
         }).catch(function(error)
         {
             reject(error);
@@ -54,9 +31,10 @@ module.exports=
          */
         main: function(requestURL, request)
         {
+            var page = request.query.page;
             return new Promise(function(resolve, reject)
             {
-                Promise.all([renderRecentPosts(), require("../sidebar/sidebar.js").main()]).then(function(content)
+                Promise.all([renderRecentPosts(requestURL, page), require("../sidebar/sidebar.js").main()]).then(function(content)
                 {
                     resolve(content.join(''));
                 }).catch(function(error)

posts/posts.js

@@ -1,7 +1,4 @@
-//file io
-const utils = require('../utils/utils.js');
-
-//DB queries
+/** DB queries */
 const sql = require('../utils/sql');
 
 
@@ -9,7 +6,6 @@ const sql = require('../utils/sql');
  * Function responsible for calling the appropriate sql requests to query
  * database and serve correct blog post
  *
- * @param res the result sent to the client
  * @param requestURL url requested from client
  * @return {*|Promise} returns a resolved promise to preserve execution order
  */
@@ -30,7 +26,7 @@ const renderPost = function(requestURL)
                 }
                 else
                 {
-                    return utils.print404();
+                    reject("Page Not Found");
                 }
             }).then(function(html)
             {
@@ -42,10 +38,7 @@ const renderPost = function(requestURL)
         }
         else
         {
-            utils.print404().then(function(html)
-            {
-               resolve("<div class='col-md-8'>" + html + "</div>");
-            });
+            reject("Page Not Found");
         }
     });
 };
@@ -62,7 +55,8 @@ module.exports=
     {
         return new Promise(function(resolve, reject)
         {
-            Promise.all([renderPost(requestURL), require("../sidebar/sidebar.js").main()]).then(function(content)
+            Promise.all([renderPost(requestURL),
+                require("../sidebar/sidebar.js").main()]).then(function(content)
             {
                 resolve(content.join(''));
             }).catch(function(error)

posts/renderBatchOfPreviewes.js

@@ -0,0 +1,55 @@
+module.exports=
+    {
+        /**
+         * Renders a bunch of blog post  previews to the user
+         *
+         * @param baseURL-- url of the page
+         * @param posts -- sql data about the posts to render
+         * @param currentPage -- the current page to render
+         * @param numOfPosts -- number of posts to render
+         * @returns {Promise} renders the html of the posts
+         */
+        main: function(baseURL, posts, currentPage, numOfPosts)
+        {
+            if(typeof currentPage == "undefined")
+            {
+                currentPage = 1;
+            }
+            else
+            {
+                currentPage = Number(currentPage);
+            }
+
+            return new Promise(function(resolve, reject)
+            {
+                const promises = [];
+                for(var i = (currentPage-1) * numOfPosts; i < (currentPage-1) * numOfPosts + numOfPosts; i++)
+                {
+                    if(i < posts.length)
+                    {
+                        promises.push(new Promise(function(res, rej)
+                        {
+                            require("../posts/singlePost.js")
+                                .renderPreview(posts[i]).then(function(html)
+                            {
+                                res(html);
+                            }).catch(function(error)
+                            {
+                                reject(error)
+                            })
+                        }));
+                    }
+                }
+
+                promises.push(require('../posts/renderNextBar').main(baseURL, currentPage, numOfPosts, posts.length));
+
+                Promise.all(promises).then(function(content)
+                {
+                    resolve("<div class='col-md-8'>" + content.join('') + "</div>");
+                }).catch(function(error)
+                {
+                    reject(error);
+                });
+            });
+        }
+    };

posts/renderNextBar.js

@@ -0,0 +1,66 @@
+/**
+ * Determines if the requested page is out of bounds
+ *
+ * @param page current page
+ * @param postsPerPage - number of posts rendered on each page
+ * @param totalPosts - total posts in this category/total
+ * @returns {boolean} if this is a valid page
+ */
+const isValidPage = function(page, postsPerPage, totalPosts)
+{
+    return !(page === 0 || page -1 >= totalPosts/postsPerPage);
+};
+
+module.exports=
+    {
+        /**
+         * Renders two buttons on the bottom of the page to
+         * go to the left or right
+         *
+         * Used by the home page and categories pages
+         * @param baseURL -- base url of page being rendered
+         * @param currentPage -- current page being rendered
+         * @param postsPerPage -- number of posts on each page
+         * @param totalPosts -- total amount of posts in the category
+         * @returns {Promise} promise which renders the buttons
+         */
+        main: function(baseURL, currentPage, postsPerPage, totalPosts)
+        {
+            return new Promise(function(resolve, reject)
+            {
+
+                if(!isValidPage(currentPage, postsPerPage, totalPosts))
+                {
+                    reject("Invalid Page");
+                }
+
+                var nextPage = currentPage + 1;
+                var previousPage = currentPage - 1;
+
+                var olderPosts = "";
+                var newerPosts = "";
+
+                if (isValidPage(previousPage, postsPerPage, totalPosts))
+                {
+                    newerPosts = "<button class=\"btn btn-secondary btn-lg " +
+                        "w3-padding-large w3-white w3-border\"  onclick=\"location.href='" +
+                        baseURL + "?page=" + previousPage +
+                        "'\"><b>Newer Posts &raquo;</b></button>";
+                }
+
+                if (isValidPage(nextPage, postsPerPage, totalPosts))
+                {
+                    olderPosts = "<button class=\"btn btn-secondary btn-lg " +
+                        "w3-padding-large w3-white w3-border\"  onclick=\"location.href='" +
+                        baseURL + "?page=" + nextPage +
+                        "'\"><b>Older Posts &raquo;</b></button>";
+                }
+
+                resolve("    <div class=\"row\">\n" +
+                    "        <div class=\"col-6\">" + newerPosts + "</div>\n" +
+                    "        <div class=\"col-6\"><span class=\"float-right\">" + olderPosts + "</span></div>\n" +
+                    "    <br><br></div>");
+            })
+
+        }
+    };

sites/blog.js

@@ -8,6 +8,9 @@ const contentLoader = require('../includes/staticContentServer.js');
 //caching program to make the application run faster
 const cache = require('memory-cache');
 
+//file io
+const utils = require('../utils/utils.js');
+
 /**
  * @author Jeffery Russell 11-3-18
  *
@@ -38,7 +41,12 @@ module.exports=
             }
             else
             {
-                const html = cache.get(filename);
+                var page = request.query.page;
+                if(typeof page == "undefined")
+                    page = 1;
+                page = Number(page);
+
+                const html = cache.get(filename + "?page=" + page);
 
                 result.writeHead(200, {'Content-Type': 'text/html'});
                 if (html == null) {
@@ -54,9 +62,12 @@ module.exports=
 
                         if (urlSplit.length >= 2 && urlSplit[1] === 'category') //single category page
                             file = "../posts/category.js";
-
                         else
+                        {
                             file = "../posts/posts.js";
+                            page = 1; // all posts are single page, everyone must be one to ensure
+                            // cache is not tricked into storing same blog post a ton of times
+                        }
                     }
 
                     Promise.all([includes.printHeader(),
@@ -65,12 +76,15 @@ module.exports=
                     {
                         result.write(content.join(''));
                         result.end();
-                        cache.put(filename, content.join(''));
-
+                        cache.put(filename + "?page=" + page, content.join(''));
                     }).catch(function (err)
                     {
-                        console.log(err);
-                        throw err;
+                        cache.del(filename + "?page=" + page);
+                        utils.print404().then(function(content)
+                        {
+                            result.write(content);
+                            result.end();
+                        })
                     });
                 }
                 else

sites/projects.js

@@ -1,6 +1,3 @@
-//file io
-const utils = require('../utils/utils.js');
-
 //used to parse the request URL
 const url = require('url');
 

utils/sql.js

@@ -196,7 +196,7 @@ module.exports=
      */
     getRecentPostSQL: function()
     {
-        return fetch("select * from posts order by post_id desc limit 10");
+        return fetch("select * from posts order by post_id desc");
     },