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Blogging on programming and life in general.

  • For one of my side projects, I was asked to use Butter CMS to allow for basic blog integration using JavaScript. I have never heard or used Butter CMS before and was intrigued to know more about the platform.

    Butter CMS is another headless CMS variant that allows a developer to utilise API endpoints to push content to an application via an arrange of approaches. So nothing new here. Just like any headless CMS, the proof is in the pudding when it comes to the following factors:

    • Quality of features
    • Ease of integration
    • Price points
    • Quality of documentation

    I haven't had a chance to properly look into what Butter CMS fully has to offer, but from what I have seen from working on the requirements for this side project I was pleasently surprised. Found it really easy to get setup with minimal amount of fuss! For this project I used Butter CMS's Blog Engine package, which does exactly what it says on the tin. All the fields you need for writing blog posts are already provided.

    JavaScript Code

    My JavaScipt implementation is pretty basic and provides the following functionality:

    • Outputs a list of posts consisting of title, date and summary text
    • Pagination
    • Output a single blog post

    All key functionality is derived from the "ButterCMS" JavaScript file:

    /*****************************************************/
    /*                    Butter CMS                                 */
    /*****************************************************/
    var ButterCMS =
    {
        ButterCmsObj: null,
    
        "Init": function () {
            // Initiate Butter CMS.
            this.ButterCmsObj = new ButterCmsBlogData();
            this.ButterCmsObj.Init();
        },
        "GetBlogPosts": function () {
            BEButterCMS.ButterCmsObj.GetBlogPosts(1);
        },
        "GetSinglePost": function (slug) {
            BEButterCMS.ButterCmsObj.GetSinglePost(slug);
        }
    };
    
    /*****************************************************/
    /*                Butter CMS Data                         */
    /*****************************************************/
    function ButterCmsBlogData() {
        var apiKey = "<Enter API Key>",
            baseUrl = "/",
            butterInstance = null,
            $blogListingContainer = $("#posts"),
            $blogPostContainer = $("#post-individual"),
            pageSize = 10;
    
        // Initialise of the ButterCMSData object get the data.
        this.Init = function () {
            getCMSInstance();
        };
    
        // Returns a list of blog posts.
        this.GetBlogPosts = function (pageNo) {
            // The blog listing container needs to be cleared before any new markup is pushed.
            // For example when the next page of data is requested.
            $blogListingContainer.empty();
    
            // Request blog posts.
            butterInstance.post.list({ page: pageNo, page_size: pageSize }).then(function (resp) {
                var body = resp.data,
                    blogPostData = {
                        posts: body.data,
                        next_page: body.meta.next_page,
                        previous_page: body.meta.previous_page
                    };
    
                for (var i = 0; i < blogPostData.posts.length; i++) {
                    $blogListingContainer.append(blogPostListItem(blogPostData.posts[i]));
                }
    
                //----------BEGIN: Pagination--------------//
    
                $blogListingContainer.append("<div>");
    
                if (blogPostData.previous_page) {
                    $blogListingContainer.append("<a class=\"page-nav\" href=\"#\" data-pageno=" + blogPostData.previous_page + " href=\"\">Previous Page</a>");
                }
    
                if (blogPostData.next_page) {
                    $blogListingContainer.append("<a class=\"page-nav\" href=\"#\" data-pageno=" + blogPostData.next_page + " href=\"\">Next Page</a>");
                }
    
                $blogListingContainer.append("</div>");
    
                paginationOnClick();
    
                //----------END: Pagination--------------//
            });
        };
    
        // Retrieves a single blog post based on the current URL of the page if a slug has not been provided.
        this.GetSinglePost = function (slug) {
            var currentPath = location.pathname,
                blogSlug = slug === null ? currentPath.match(/([^\/]*)\/*$/)[1] : slug;
    
            butterInstance.post.retrieve(blogSlug).then(function (resp) {
                var post = resp.data.data;
    
                $blogPostContainer.append(blogPost(post));
            });
        };
    
        // Renders the HTML markup and fields for a single post.
        function blogPost(post) {
            var html = "";
    
            html = "<article>";
    
            html += "<h1>" + post.title + "</h1>";
            html += "<div>" + blogPostDateFormat(post.created) + "</div>";
            html += "<div>" + post.body + "</div>";
            
            html += "</article>";
    
            return html;
        }
    
        // Renders the HTML markup and fields when listing out blog posts.
        function blogPostListItem(post) {
            var html = "";
    
            html = "<h2><a href=" + baseUrl + post.url + ">" + post.title + "</a></h2>";
            html += "<div>" + blogPostDateFormat(post.created) + "</div>";
            html += "<p>" + post.summary + "</p>";
    
            if (post.featured_image) {
                html += "<img src=" + post.featured_image + " />";
            }
    
            return html;
        }
    
        // Set click event for previous/next pagination buttons and reload the current data.
        function paginationOnClick() {
            $(".page-nav").on("click", function (e) {
                e.preventDefault();
                var pageNo = $(this).data("pageno"),
                    butterCmsObj = new ButterCmsBlogData();
    
                butterCmsObj.Init();
                butterCmsObj.GetBlogPosts(pageNo);
            });
        }
    
        // Format the blog post date to dd/MM/yyyy HH:mm
        function blogPostDateFormat(date) {
            var dateObj = new Date(date);
    
            return [dateObj.getDate().padLeft(), (dateObj.getMonth() + 1).padLeft(), dateObj.getFullYear()].join('/') + ' ' + [dateObj.getHours().padLeft(), dateObj.getMinutes().padLeft()].join(':');
        }
    
        // Get instance of Butter CMS on initialise to make one call.
        function getCMSInstance() {
            butterInstance = new Butter(apiKey);
        }
    }
    
    // Set a prototype for padding numerical values.
    Number.prototype.padLeft = function (base, chr) {
        var len = (String(base || 10).length - String(this).length) + 1;
    
        return len > 0 ? new Array(len).join(chr || '0') + this : this;
    };
    

    To get a list of blog posts:

    // Initiate Butter CMS.
    BEButterCMS.Init();
    
    // Get all blog posts.
    BEButterCMS.GetBlogPosts();
    

    To get a single blog post, you will need to pass in the slug of the blog post via your own approach:

    // Initiate Butter CMS.
    BEButterCMS.Init();
    
    // Get single blog post.
    BEButterCMS.GetSinglePost(postSlug);
    
  • If you have many sites running on your installation of Windows Server, you will soon find that there will be an accumulation of logs generated by IIS. Through my niavity, I presumed that there is a default setting in IIS that would only retain logs for a specific period of time. It is only when I started noticing over the last few weeks the hard disk space was slowly getting smaller and smaller.

    Due to my sheer embaressment, I won't divulge how much space the logs had taken up. All I can say, it was quite a substantial amount. :-)

    After some Googling online, I came across a Powershell script (which can be found here), that solved all my problems. The script targets your IIS logs folder and recusively looks for any file that contains ".log" for deletion. Unfortunately, the script did not run without making some minor modifications to the original source. This is due to changes in versions of Powershell since the post was written 3 years ago.

    $logPath = "C:\inetpub\logs\LogFiles" 
    $maxDaystoKeep = -5
    $cleanupRecordPath = "C:\Log_Cleanup.log" 
    
    $itemsToDelete = dir $logPath -Recurse -File *.log | Where LastWriteTime -lt ((get-date).AddDays($maxDaystoKeep)) 
    
    If ($itemsToDelete.Count -gt 0)
    { 
        ForEach ($item in $itemsToDelete)
        { 
            "$($item.FullName) is older than $((get-date).AddDays($maxDaystoKeep)) and will be deleted." | Add-Content $cleanupRecordPath 
            Remove-Item $item.FullName -Verbose 
        } 
    } 
    Else
    { 
        "No items to be deleted today $($(Get-Date).DateTime)." | Add-Content $cleanupRecordPath 
    }    
    
    Write-Output "Cleanup of log files older than $((get-date).AddDays($maxDaystoKeep)) completed!" 
    
    Start-Sleep -Seconds 10
    

    If you're ever so inclined, hook this script up to a Scheduled Task to run on a daily basis to keep your log files in order.

  • Published on
    -
    1 min read

    The Biggest E-commerce of My Kentico Career!

    I recently blogged about a very large Kentico E-commerce build I was involved with at Syndicut that contained around 2 million products. Trust me, this is a major feat in itself! A lot of customisation and performance improvements were made to the Kentico build to accomodate the sheer volume of products.

    A follow up post will be published soon that will detail the issues we experienced in developing a Kentico site that has to manage more products you could ever imagine and our solution to those issues.

    You can have a read about the project and some of my highlights here: https://medium.com/syndicutstudio/welcome-to-our-biggest-kentico-e-commerce-build-yet-9bd2109955e0.

  • A website can tell the public a lot about you, from the things you want people to see and other things you probably would not. HTTP Headers can divulge things about your website that you wouldn't necessarily want to make public and its up to the individual to make a decision on what headers they're willing to expose. But what I would recommend is to at least analyse any site prior to moving to a production environment.

    Why all of a sudden am I talking about questioning your website HTTP Headers?

    It was only by chance when perusing StackOverflow I came across a question about securing HTTP headers, I was directed to a site called securityheaders.io. I immediately entered this very site for scanning, thinking it would fare quite well. But boy oh boy was I wrong!:

    Security Headers (Before)

    Based on this result, does this make my website vulnerable? To a certain extent yes. By default you're exposing some key information to potential hackers about how your website is built. For example, here is a simple list of HTTP Headers that could be returned from the server:

    • Web server
    • Framework version
    • Cache handling
    • Cross-site scripting access
    • Referrer policies

    Now based on that list alone, what HTTP headers would you hide? From having my eyes opened by the report generated by securityheaders.io, as a minimum I would hide anything that shows what technology, framework and server platform I am using. If there happens to be an exploit on the very server or technology you are using, we don't want the whole world to know that especially if you happen to be hosting a high traffic website.

    I decided to correct all the issues highlighted by securityheaders.io and spent additional time obfuscating some additional headers. Now I can proudly say I've passed. There is just one blemish against the report to do with the "Content-Security-Policy" header, which defines approved sources of content that the browser may load.

    Security Headers (After)

    I been tweaking around with the rules for this header and I'll be honest when I say it shafted the administration dashboard of my the content management system I use for my site - Kentico CMS. So before I reinstate the header, I need a little more time tweaking.

    Another great site to use to analyse the security of your site (.NET sites only) is ASafaWeb, which scans for common configuration vulnerabilities.

    Recommended Links

  • Whilst making a request to one of my API endpoints for an iOS application, I came across a very unhelpful error: "Invalid response for blob". I couldn't really understand why React Native was complaining about this single API endpoint, since all my other endpoints did not encounter this error.

    React Native: Invalid Response For Blob

    The API endpoint in question is a pretty simple email address validator. If the users email address is unique and passes all verification checks, the endpoint will either return a 200 (OK) or 400 (Bad Request) along with a response containing the error. For those who understand ASP.NET Web API development, my endpoint is as follows:

    /// <summary>
    /// Check if a user's email address is not already in user along with other string validation checks.
    /// </summary>
    /// <param name="email"></param>
    /// <returns></returns>
    [HttpPost]
    [AllowAnonymous]
    [Route("EmailAddressValidator")]
    public HttpResponseMessage EmailAddressValidator(string email)
    {
        if (UserLogic.IsEmailValid(email, out string error)) // UserLogic.IsEmailValid() method carries out email checks...
            return Request.CreateResponse(HttpStatusCode.OK);
    
        return Request.CreateResponse(HttpStatusCode.BadRequest, new ErrorModel { Error = error });
    }
    

    So pretty simple stuff!

    Weirdly enough the "Invalid response for blob" issue did not occur within my endpoint when the users email address did not pass the required checks, thus returning a 400 error and a response detailing the error. It was only when a 200 response was returned without a value.

    There seems to be a bug in the React Native environment when it comes to dealing with empty API responses. The only way I could get around this, is to always ensure all my API endpoints returned some form of response. Very strange! I suggest all you fellow React Native developers do the same until a fix is put in place.

    The issue has already been logged so I will be keeping an eye on a release for a fix.

    Update (16/07/2018)

    I wasn't too sure to whether anything had been done in regards to the fix since writing this post as there was no update to the Github issue that was first logged on the 5th March. So I decided to share this very post to a React Native group on Reddit to get some form of answer. Within a short period of time, I was told this issue has been fixed in React Native version 0.56.

  • Earlier this week a post I wrote for C# Corner was published. It was about an alternative to use the very well known SQL Server "IN" condition when working with many values. I discuss storing a list of values you would normally pass directly into your "IN" condition for querying to a User Defined Data Type.

    There will probably be a very small number of cases where additional steps I write in the post will need to be carried out. Afterall, SQL Server has a very large limit on the number of values the “IN” condition can handle, based on the length of instruction (max 65k).

    Check it out here: http://www.c-sharpcorner.com/blogs/alternative-to-sql-in-condition-when-working-with-many-values

  • I decided to write this blog post after one of my fellow Kentico Cloud developer Matt Nield tweeted the following last week:

    So happy to see this coming to Kentico Cloud! The amount to times I yearned for something I could use to clear cache!
    — Surinder Bhomra (@SurinderBhomra) July 13, 2017

    Webhook capability is something I have been yearning for since I built my first Kentico Cloud project and this feature cannot come soon enough! It will really take the Kentico Cloud headless CMS integration within our applications to the next level. One of the main things I am looking forward to is using webhooks is to develop a form of dependency caching, so when content is updated in Kentico Cloud, the application can reflect these changes.

    In fact, I am so excited to have this feature in my hands for my caching needs, I have already started developing something I could potentially use in time for the Q3 2017 release - should be any time now.


    As we all know, to not only improve overall performance of your application as well as reducing requests to the Kentico Cloud API, we are encouraged to set a default cache duration. There is documentation on the different routes to accomplish this:

    1. Controller-level - using OutputCache attribute
    2. CachedDeliveryClient class - provided by the Kentico Cloud Boilerplate that acts as a wrapper around the original DeliveryClient object to easily cache data returned from the API for a fixed interval.

    I personally prefer caching at controller level, unless the application is doing something very complex at runtime for manipulating incoming data. So in the mean time whilst I wait for webhook functionality to be released, I decided to create a custom controller attribute called "KenticoCacheAttribute", that will only start the caching process only if the application is not in debug mode.

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Web;
    using System.Web.Mvc;
    
    namespace Site.Web.Attributes
    {
        public class KenticoCacheAttribute : OutputCacheAttribute
        {
            public KenticoCacheAttribute()
            {
                Duration = HttpContext.Current.IsDebuggingEnabled ? 0 : int.Parse(ConfigurationManager.AppSettings["KenticoCloud.CacheDuration"]);
            }
        }
    }
    

    The "KenticoCacheAttribute" inherits the OutputCacheAttribute class, which gives me additional control to when I'd like the caching process to happen. In this case, the cache duration is set within the web.config.

    I found the one main benefit of my custom controller attribute is that I will never forget to start caching pages on my website when it comes to deployment to production, since we never want our website to have debugging enabled unless we're in a development environment. This also works the other way. We're not too concerned about caching in a development environment as we always want to see changes in incoming data straight away.

    The new cache attribute is used in the exact same approach as OutputCacheAttribute, in the following way:

    [Route("{urlSlug}")]
    [KenticoCacheAttribute(VaryByParam = "urlSlug")]
    public async Task<ActionResult> Detail(string urlSlug)
    {
         // Do something...
    
        return View();
    }
    

    This is a very simple customisation I found useful through my Kentico Cloud development.

    The custom attribute I created is just the start on how I plan on integrating cache managment for Kentico Cloud applications. When webhook capability is released, I can see further improvements being made, but may require a slightly different approach such as developing a custom MVC Action Filter instead.

  • I like to keep my blob containers quite tidy and delete any files that would unnecessarily increase its size. For a project I was working on, I had a blob that was being used to temporarily store images a user uploaded for manipulation at a later time. I saw no reason to keep these files for no longer than 24 hours. An Azure WebJob seemed an ideal solution to do this.

    I could've left the blob container to stagnate and fester over time and the reasoning behind creating a cleanup task wasn't from a cost point of view. A blob container is very reasonably priced for the amount of storage and requests I would be making. I was more concerned about performance for times where I would be trawling through many thousands of files to get back the image a user had uploaded for temporary use by my web application.

    Creating an Azure WebJob is very easy and versatile. You have the flexibility to develop a WebJob by creating the following scripts or programs:

    • .cmd, .bat, .exe (using windows cmd)
    • .ps1 (using powershell)
    • .sh (using bash)
    • .php (using php)
    • .py (using python)
    • .js (using node)
    • .jar (using java)

    In this post, I will be developing my WebJob using a Console Application that will generate an executable. In Visual Studio 2017, there are two ways you can go about creating a project for your WebJob:

    1. Console Application project
    2. Selecting Azure WebJob project - which you will find under the "Cloud" category.

    If you create your WebJob using a Console Application, you will still have the option later on to "Publish as an Azure WebJob..." when right-clicking on the project. In the code below I happened to be using a Console Application only because I didn't even know a Azure WebJob project existed until after I completed development on my project. Doh!

    Program.cs

    I have created a new project called "Site.AzueWebJob.Cleanup". The project uses the following two Azure nuget packages:

    
    namespace Site.AzureWebJob.Cleanup
    {
        class Program
        {
            static void Main(string[] args)
            {
                try
                {
                    CloudStorageAccount storageAccount = CloudStorageAccount.Parse("<Insert Storage Connection String Here>");
    
                    CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();
                    CloudBlobContainer dataContainer = blobClient.GetContainerReference("<Blob container name>");
    
                    Console.WriteLine("Hourly threshold to remove records: {0}", ConfigurationManager.AppSettings["Azure.CleanupHours"]);
    
                    #region Retrieve all data items greater than 24 hours and delete them
    
                    Console.WriteLine("Retrieving old data files...");
    
                    // Get files where the "Last Modified Date" is olders than 24 hours.
                    IEnumerable<CloudBlob> oldData = dataContainer.ListBlobs()
                                    .OfType<CloudBlob>()
                                    .Where(b => b.Properties.LastModified.Value.Date < DateTime.Now.AddHours(int.Parse(ConfigurationManager.AppSettings["Azure.CleanupHours"].ToString()) * -1));
    
                    IList<CloudBlob> dataBlobs = oldData as IList<CloudBlob> ?? oldData.ToList();
    
                    Console.WriteLine("Data records retrieved: {0}.", dataBlobs.Count);
                    Console.WriteLine("Removing old data files...");
    
                    // Loop through the files and delete if they exist.
                    foreach (CloudBlob dataBlob in dataBlobs)
                    {
                        bool isDeleted = dataBlob.DeleteIfExists();
    
                        if (isDeleted)
                            Console.WriteLine("Deleted: {0}.", dataBlob.Name);
                    }
    
                    #endregion
    
                    Console.WriteLine("Removing old data complete.");
                }
                catch (Exception ex)
                {
                    Console.WriteLine("Error cleaning container files: {0}", ex.Message);
                }
    
                Console.WriteLine("Clean Containers WebJob complete.");
            }
        }
    }
    

    There isn't really much to it. All I am doing is retrieving all files that are older than 24 hours (value set within App.config app setting called: "Azure.CleanupHours") and then carrying out the delete process by looping through any records returned.

    The most safest way to delete a file is to use the CloudBlob.DeleteIfExists() call. As the method name suggests, it will only delete a file if it exists. Using the CloudBlob.Delete() will cause an exception if for some reason the file isn't there and will require additional error handling.

    Final Steps

    Now that we have our Azure WebJob ready to go, the only thing left is to publish to your Azure Web App by simply right-clicking on your project and selecting: "Publish as an Azure WebJob...". Here you will connect to your Azure instance and have the options to choose how your WebJob should run:

    • Continuously
    • On Demand
    • On Schedule
  • Reading and writing files from an external application to Saleforce has always resulted in giving me quite the headache... Writing to Salesforce probably exacerbates things more than reading. I will aim to detail in a separate post on how you can write a file to Salesforce.

    In this post I will demonstrate how to read a file found in the "Notes & Attachments" area of Salesforce as well as getting back all information about that file.

    The first thing we need is our attachment object, to get back all information about our file. I created one called "AttachmentInfo":

    public class AttachmentInfo
    {
        public string Id { get; set; }
        public string Name { get; set; }
        public string Description { get; set; }
        public string BodyLength { get; set; }
        public string ContentType { get; set; }
        public byte[] FileBytes { get; set; }
    }
    

    I created two methods in a class named "AttachmentInfoProvider". Both methods are pretty straight-forward and retrieve data from Salesforce using a custom GetRows() method that is part of another class object I created: ObjectDetailInfoProvider. You can get the code for this from the following blog post - Salesforce .NET API: Select/Insert/Update Methods.

    GetAttachmentsDataByParentId() Method

    /// <summary>
    /// Gets all attachments that belong to an object. For example a contact.
    /// </summary>
    /// <param name="parentId"></param>
    /// <param name="fileNameMatch"></param>
    /// <param name="orderBy"></param>
    /// <returns></returns>
    public static async Task<List<AttachmentInfo>> GetAttachmentsDataByParentId(string parentId, string fileNameMatch, string orderBy)
    {
        string cacheKey = $"GetAttachmentsByParentId|{parentId}|{fileNameMatch}";
    
        List<AttachmentInfo> attachments = CacheEngine.Get<List<AttachmentInfo>>(cacheKey);
    
        if (attachments == null)
        {
            string whereCondition = string.Empty;
    
            if (!string.IsNullOrEmpty(fileNameMatch))
                whereCondition = $"Name LIKE '%{fileNameMatch}%'";
    
            List<dynamic> attachmentObjects = await ObjectDetailInfoProvider.GetRows("Attachment", new List<string> {"Id", "Name", "Description", "Body", "BodyLength", "ContentType"}, whereCondition, orderBy);
    
            if (attachmentObjects.Any())
            {
                attachments = attachmentObjects.Select(attObj => new AttachmentInfo
                {
                    Id = attObj.Id,
                    Name = attObj.Name,
                    Description = attObj.Description,
                    BodyLength = attObj.BodyLength,
                    ContentType = attObj.ContentType
                }).ToList();
    
                // Add collection of pick list items to cache.
                CacheEngine.Add(attachments, cacheKey, 15);
            }
        }
    
        return attachments;
    }
    

    The GetAttachmentsDataByParentId() method takes in three parameters:

    • parentId: The ID that links an attachment to another object. For example, a contact.
    • fileNameMatch: The name of the file you wish to search for. For most flexibility, a wildcard search is performed.
    • orderBy: Order the returned dataset.

    If you're thinking this method alone will return the file itself, you'd be disappointed - this is where our next method GetFile() comes into play.

    GetFile() Method

    /// <summary>
    /// Gets attachment in its raw form ready for transformation to a physical file, in addition to its file attributes.
    /// </summary>
    /// <param name="attachmentId"></param>
    /// <returns></returns>
    public static async Task<AttachmentInfo> GetFile(string attachmentId)
    {
        List<dynamic> attachmentObjects = await ObjectDetailInfoProvider.GetRows("Attachment", new List<string> {"Id", "Name", "Description", "BodyLength", "ContentType"}, $"Id = '{attachmentId}'", string.Empty);
    
        if (attachmentObjects.Any())
        {
            AttachmentInfo attachInfo = new AttachmentInfo();
    
            #region Get Core File Information
    
            attachInfo.Id = attachmentObjects[0].Id;
            attachInfo.Name = attachmentObjects[0].Name;
            attachInfo.BodyLength = attachmentObjects[0].BodyLength;
            attachInfo.ContentType = attachmentObjects[0].ContentType;
    
            #endregion
    
            #region Get Attachment As Byte Array
    
            Authentication salesforceAuth = await AuthenticationResponse.Rest();
    
            HttpClient queryClient = new HttpClient();
    
            string apiUrl = $"{SalesforceConfig.PlatformUrl}/services/data/v37.0/sobjects/Attachment/{attachmentId}/Body";
    
            HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Get, apiUrl);
            request.Headers.Add("Authorization", $"OAuth {salesforceAuth.AccessToken}");
            request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
    
            HttpResponseMessage response = await queryClient.SendAsync(request);
    
            if (response.StatusCode == HttpStatusCode.OK)
                attachInfo.FileBytes = await response.Content.ReadAsByteArrayAsync();
    
            #endregion
    
            return attachInfo;
        }
        else
        {
            return null;
        }
    }
    

    An attachment ID is all we need to get back a file in its raw form. You will probably notice there is some similar functionality happening in this method where I am populating all fields of the AttachmentInfo object, just like the GetAttachmentsDataByParentId() method I detailed above. The only difference being is the fact this time round only a single file is returned.

    The reason behind this approach comes from a performance standpoint. I could have modified the GetAttachmentsDataByParentId() method to also return the file in its byte form. However, this didn't seem a good approach, since we could be outputting multiple files large in size. So making a separate call to focus on getting the physical file seemed like a wise approach.

    To take things one step further, you can render the attachment from Salesforce within your ASP.NET application using a Generic Handler (.ashx file):

    <%@ WebHandler Language="C#" Class="SalesforceFileHandler" %>
    
    using System;
    using System.Text;
    using System.Threading.Tasks;
    using System.Web;
    using Site.Salesforce;
    using Site.Salesforce.Models.Attachment;
    
    public class SalesforceFileHandler : HttpTaskAsyncHandler
    {
        public override async Task ProcessRequestAsync(HttpContext context)
        {
            string fileId = context.Request.QueryString["FileId"];
        
            // Check if there is a File ID in the query string.
            if (!string.IsNullOrEmpty(fileId))
            {
                AttachmentInfo attachment = await AttachmentInfoProvider.GetFile(fileId);
    
                // If attachment is returned, render to the browser window.
                if (attachment != null)
                {
                    context.Response.Buffer = true;
    
                    context.Response.AppendHeader("Content-Disposition", $"attachment; filename=\"{attachment.Name}\"");
    
                    context.Response.BinaryWrite(attachment.FileBytes);
    
                    context.Response.OutputStream.Write(attachment.FileBytes, 0, attachment.FileBytes.Length);
                    context.Response.ContentType = attachment.ContentType;
                }
                else
                {
                    context.Response.ContentType = "text/plain";
                    context.Response.Write("Invalid File");
                }
            }
            else
            {
                context.Response.ContentType = "text/plain";
                context.Response.Write("Invalid Request");
            }
    
            context.Response.Flush();
            context.Response.End();
        }
    }
    
  • Ever since I re-developed my website in Kentico 10 using Portal Templates, I have been a bit more daring when it comes to immersing myself into the inner depths of Kentico's API and more importantly - K# macro development. One thing that has been on my list of todo's for a long time was to create a custom macro extension that would render all required META open graph tags in a page.

    Adding these type of META tags using ASPX templates or MVC framework is really easy to do when you have full control over the page markup. I'll admit, I don't know if there is already an easier way to do what I am trying to accomplish (if there is let me know), but I think this macro is quite flexible with capability to expand the open graph output further.

    This is how I currently render the Meta HTML within my own website at masterpage level (click for a larger image):

    Open Graph HTML In Masterpage

    I instantly had problems with this approach:

    1. The code output is a mess.
    2. Efficiency from a performance standpoint does not meet my expectations.
    3. Code maintainability is not straight-forward, especially if you have to update this code within the Page Template Header content.

    CurrentDocument.OpenGraph() Custom Macro

    I highly recommend reading Kentico's documentation on Registering Custom Macro Methods before adding my code. It will give you more of an insight on what can be done that my blog post alone will not cover. The implementation of my macro has been developed for a Kentico site that is a Web Application and has been added to the "Old_App_Code" directory.

    // Registers methods from the 'CustomMacroMethods' container into the "String" macro namespace
    [assembly: RegisterExtension(typeof(CustomMacroMethods), typeof(TreeNode))]
    namespace CMSApp.Old_App_Code.Macros
    {
        public class CustomMacroMethods : MacroMethodContainer
        {
            [MacroMethod(typeof(string), "Generates Open Graph META tags", 0)]
            [MacroMethodParam(0, "param1", typeof(string), "Default share image")]
            public static object OpenGraph(EvaluationContext context, params object[] parameters)
            {
                if (parameters.Length > 0)
                {
                    #region Parameter variables
    
                    // Parameter 1: Current document.
                    TreeNode tnDoc = parameters[0] as TreeNode;
                    
                    // Paramter 2: Default social icon.
                    string defaultSocialIcon = parameters[1].ToString();
    
                    #endregion
    
                    string metaTags = CacheHelper.Cache(
                        cs =>
                        {
                            string domainUrl = $"{HttpContext.Current.Request.Url.Scheme}{Uri.SchemeDelimiter}{HttpContext.Current.Request.Url.Host}{(!HttpContext.Current.Request.Url.IsDefaultPort ? $":{HttpContext.Current.Request.Url.Port}" : null)}";
    
                            StringBuilder metaTagBuilder = new StringBuilder();
    
                            #region General OG Tags
                            
                            metaTagBuilder.Append($"<meta property=\"og:title\" content=\"{DocumentContext.CurrentTitle}\"/>\n");
    
                            if (tnDoc.ClassName == KenticoConstants.Page.BlogPost)
                                metaTagBuilder.Append($"<meta property=\"og:description\" content=\"{tnDoc.GetValue("BlogPostSummary", string.Empty).RemoveHtml()}\" />\n");
                            else
                                metaTagBuilder.Append($"<meta property=\"og:description\" content=\"{tnDoc.DocumentPageDescription}\" />\n");
    
                            if (tnDoc.GetValue("ShareImageUrl", string.Empty) != string.Empty)
                                metaTagBuilder.Append($"<meta property=\"og:image\" content=\"{domainUrl}{tnDoc.GetStringValue("ShareImageUrl", string.Empty).Replace("~", string.Empty)}?width=600\" />\n");
                            else
                                metaTagBuilder.Append($"<meta property=\"og:image\" content=\"{domainUrl}/{defaultSocialIcon}\" />\n");
    
                            #endregion
    
                            #region Twitter OG Tags
    
                            if (tnDoc.ClassName == KenticoConstants.Page.BlogPost || tnDoc.ClassName == KenticoConstants.Page.GenericContent)
                                metaTagBuilder.Append("<meta property=\"og:type\" content=\"article\" />\n");
                            else
                                metaTagBuilder.Append("<meta property=\"og:type\" content=\"website\" />\n");
    
                            metaTagBuilder.Append($"<meta name=\"twitter:site\" content=\"@{Config.Twitter.Account}\" />\n");
                            metaTagBuilder.Append($"<meta name=\"twitter:title\" content=\"{DocumentContext.CurrentTitle}\" />\n");
                            metaTagBuilder.Append("<meta name=\"twitter:card\" content=\"summary\" />\n");
    
                            if (tnDoc.ClassName == KenticoConstants.Page.BlogPost)
                                metaTagBuilder.Append($"<meta property=\"twitter:description\" content=\"{tnDoc.GetValue("BlogPostSummary", string.Empty).RemoveHtml()}\" />\n");
                            else
                                metaTagBuilder.Append($"<meta property=\"twitter:description\" content=\"{tnDoc.DocumentPageDescription}\" />\n");
    
                            if (tnDoc.GetValue("ShareImageUrl", string.Empty) != string.Empty)
                                metaTagBuilder.Append($"<meta property=\"twitter:image\" content=\"{domainUrl}{tnDoc.GetStringValue("ShareImageUrl", string.Empty).Replace("~", string.Empty)}?width=600\" />");
                            else
                                metaTagBuilder.Append($"<meta property=\"twitter:image\" content=\"{domainUrl}/{defaultSocialIcon}\" />");
    
                            #endregion
    
                            // Setup the cache dependencies only when caching is active.
                            if (cs.Cached)
                                cs.CacheDependency = CacheHelper.GetCacheDependency($"documentid|{tnDoc.DocumentID}");
    
                            return metaTagBuilder.ToString();
                        },
                        new CacheSettings(Config.Kentico.CacheMinutes, KenticoHelper.GetCacheKey($"OpenGraph|{tnDoc.DocumentID}"))
                    );
    
                    return metaTags;
                }
                else
                {
                    throw new NotSupportedException();
                }
            }
        }
    }
    

    This macro has been tailored specifically to my site needs with regards to how I am populating the OG META tags, but is flexible enough to be modified based on a different site needs. I am carrying out checks to determine what pages are classed as "article" or "website". In this case, I am looking out for my Blog Post and Generic Content pages.

    I am also being quite specific on how the OG Description is populated. Since my website is very blog orientated, there is more of a focus to populate the description fields with "BlogPostSummary" field if the current page is a Blog Post, otherwise default to "DocumentPageDescription" field.

    Finally, I ensured that all article pages contained a new Page Type field called "ShareImageUrl", so that I have the option to choose a share image. This is not compulsory and if no image has been selected, a default share image you pass as a parameter to the macro will be used.

    Using the macro is pretty simple. In the header section of your Masterpage template, just add the following:

    Open Graph Macro Declaration

    As you can see, the OpenGraph() macro can be accessed by getting the current document and passing in a default share icon as a parameter.

    Macro Benchmark Results

    This is where things get interesting! I ran both macro implementations through Kentico's Benchmark tool to ensure I was on the right track and all efforts to develop a custom macro extension wasn't all in vain. The proof is in the pudding (as they say!).

    Old Implementation

    Total runs: 1000
    Total benchmark time: 1.20367s
    Total run time: 1.20267s
    
    Average time per run: 0.00120s
    Min run time: 0.00000s
    Max run time: 0.01700s
    

    New Implementation - OpenGraph() Custom Macro

    Total runs: 1000
    Total benchmark time: 0.33222s
    Total run time: 0.33022s
    
    Average time per run: 0.00033s
    Min run time: 0.00000s
    Max run time: 0.01560s
    

    The good news is that the OpenGraph() macro approach has performed better over my previous approach across all benchmark results. I believe caching the META tag output is the main reason for this as well as reusing the current document context when getting page values.