Blog

Tagged by 'gatsbyjs'

  • If you haven't noticed (and I hope you have), back in June I finally released an update to my website to look more pleasing to the eye. This has been a long time coming after being on the back-burner for a few years.

    Embarrassingly, I’ve always stated in my many year in reviews that I planned on redeveloping this site over the next coming year, but never came to fruition. This is partly down to time and deciding to make content a priority. If I’m honest, it’s mostly down to lacking the skills and patience in carrying out the front-end development work.

    Thankfully, I managed to knuckle down and decided to become acquainted and learnt enough about HTML and CSS to get the site where it currently stands, with the help of Tailwind CSS and an open-source base template to act as a good starting point for a novice front-end developer.

    Tailwind CSS

    Very early on, I knew the only hope I had to give this site a new look was to use a front-end framework like Tailwind CSS, requiring a minimal learning curve to produce quick results. It’s definitely not a front-end framework to be sniffed at as more than 260000 developers have used it for their design system. So it’s a framework that is here to stay - a worthwhile investment to learn.

    Tailwind CSS is predominantly a CSS framework consisting of predefined classes to build websites directly within the markup without having to write a single line of custom CSS.

    As you’re styling directly within the markup, at first glance it can be overwhelming, especially where multiple classes need to be declared on a single HTML block. A vast difference when compared to the cleanliness of builds carried out by the very skilful team from where I work.

    It’s a small trade-off in an otherwise solid framework that gives substantial benefits in productivity. Primarily because Tailwind CSS classes aren’t very specific and gives a high level of customisability without you having to concoct CSS styles.

    Even though there are many utility classes to get acquainted with, once you have an understanding of the core concepts, front-end builds become less of an uphill battle. Through rebuilding my site, I managed to quite quickly get familiarity with creating different layouts based on viewport size and modifying margins and padding.

    I found it to be a very modular and component-driven framework, helping avoid repetition. There are UI kits on the market that give good examples of the power of Tailwind CSS that you can use to help speed up development:

    Using Tailwind CSS took away my fear of front-end development without having to think about Bootstrap, BEM, SASS mix-ins, custom utility classes, purge processing, etc.

    Base Template

    I gave myself a 3-week target (not full-time) to get the new site released and this couldn't have been done without getting a head start from a base theme. I found an open-source template built by Timothy Lin on Tailwind Awesome website that suited my key requirements:

    • Clean
    • Simple
    • Elegant
    • Maintainable
    • Easily customisable

    Another developer by the name of Leo, developed another variation of this already great template where I felt it met my requirements down to a tee.

    Even though the template code-base used was developed in Next.js, this did not matter as I could easily migrate the Tailwind markup into my Gatsby JS project. Getting Tailwind set up initially for Gatsby took a little tinkering to get right and to ensure the generated CSS footprint was kept relatively small.

    As you can see from the new site build, I was able to make further modifications to suit my requirements. This in itself is a testament to the original template build quality and the power of Tailwind CSS.

    Improvements

    As well as changing the look of my site, I thought it would be an opportune time to make a few other small enhancements.

    Google Ads

    Removing Google Ads had been on the forefront of my mind ever since I moved over to Netlify to host my website. Previously, it was a way to contribute to the yearly hosting cost. Now, this is no longer of any relevance (as I'm on the free Netlify free hosting plan), especially when weighing the importance of a meagre monetary return over improving the overall website look and load times of the site.

    In its place, I have a Buy Me A Coffee profile for those who would like to support the content I write.

    Updated Version of Gatsby JS

    It seemed natural to upgrade the version of Gatsby JS from version 2 to 4 during the reworking of my site to keep up-to-date with the latest changes and remove any deprecated code.

    Upgrading from version 2 to 4 took a little longer than I'd hoped as other elements required updating such as Node and NPM packages. This resulted in a lot of breaking changes within my code-base that I had to rectify.

    The process was arduous but worth doing as I found site builds in Netlify reduced significantly.

    Gatsby Build Caching

    I briefly spoke about improved Netlify build times (above) due to efficiencies in code changes relating to upgrading to Gatsby 4. There is one more quiver to my bow to aid further build efficiencies and that is by installing the netlify-plugin-gatsby-cache plugin within Netlify - one-click install.

    I highly recommend everyone who has a Gatsby site install this plugin as it instantly reduces build times. For a website like my own that houses over 300 posts the build minutes do start to add up.

    Features Yet To Be Implemented

    Even though the new version of my site is live, there are features I still plan on implementing.

    Algolia Site Search

    As part of getting a new version of my site released in such a short period, I had to focus on the core areas and everything else was secondary. One of the features that didn’t make the cut was the site search using Algolia.

    I do plan on reinstating the site search feature at some point as I found it helpful for me to search through my older posts and surprisingly (based on the stats) visitors to the site also made use of it.

    Short-Form Content

    I like the idea of posting smaller pieces of content that doesn't have to result in very lengthy written blog posts. Not sure what I will call this new section. There are only two names that come to mind: "Short-form" or "Bytesize". It could consist of the following types of content:

    • Small, concise code snippets.
    • Links to content I found useful online that could be useful in certain technical use-cases.
    • Book recommendations.
    • Quotes.
    • Thoughts on news articles - John Gruber style!

    At one point, I wrote blog posts I categorised as Quick Tips, till this date consists of a mere four blog posts that I never added to. I think the naming of this category wasn't quite right.

    I see this section functioning in a similar fashion to Marco Heine's Today I Learned.

    My Bookmarks

    I like the idea of having single page with a bunch of links to useful sites I keep going back to. It could be sites that you have never come across before, making all the more reason to share these links.

    Closing Thoughts

    I normally find a full-site rebuild quite trying at times. This time was different and there were two reasons for this.

    Firstly, I've already built the site in Gatsby JS and involved minimal code changes, even when taking into consideration the changes needed to update to version 4. Secondly, using Tailwind CSS as a front-end framework was a very rewarding experience especially when page builds come to fruition in such a quick turnaround.

    I hope you find the new design is more aesthetically pleasing and makes reading through blog posts a more enjoyable experience.

  • I’ve recently updated my website from the ground up (something I will write in greater detail in a future post) and when it came to releasing all changes to Netlify, I was greeted by the following error in the build log:

    7:39:29 PM: $ gatsby build
    7:39:30 PM: error Gatsby requires Node.js 14.15.0 or higher (you have v12.18.0).
    7:39:30 PM: Upgrade Node to the latest stable release: https://gatsby.dev/upgrading-node-js
    

    Based on the error, it appears that the Node version installed on my machine is older than what Netlify requires... In fact, I was surprised to discover that it was very old. So I updated Node on my local environment as well as all of the NPM packages for my website.

    I now needed to ensure my website hosted in Netlify was using the same versions.

    The quickest way to update Node and NPM versions is to add the following environment variables to your site:

    NODE_VERSION = "14.15.0"
    NPM_VERSION = "8.5.5"
    

    You can also set the Node and NPM versions by adding a netlify.toml file to the root of your website project before committing your build to Netlify:

    [build.environment]
        NODE_VERSION = "14.15.0"
        NPM_VERSION = "8.5.5" 
    
  • I created a simple GatsbyJS pagination component that would work in a similar way to my earlier ASP.NET Core version, where the user will be able to paginate through a list using the standard "Previous" and "Next" links as well as selecting individual page numbers.

    Like the ASP.NET Core version, I have tried to make this pagination component very portable, so there shouldn't be any issues in adding this straight into your project. Plug and play!

    import * as React from 'react'
    import { Link } from 'gatsby'
    import PropTypes from 'prop-types'
    
    // Create URL path for numeric pagination
    const getPageNumberPath = (currentIndex, basePath) => {
      if (currentIndex === 1) {
        return basePath
      }
      
      return `${basePath}/page-${(currentIndex)}`
    }
    
    // Create an object array of pagination numbers. 
    // The number of page numbers to render is set to 5.
    const getPaginationGroup = (basePath, currentPage, pageCount, noOfPagesNos = 5) => {
        let startPage = currentPage;
    
        if (startPage === 1 || startPage === 2 || pageCount < noOfPagesNos)
            startPage = 1;
        else
            startPage -= 2;
    
        let maxPage = startPage + noOfPagesNos;
    
        if (pageCount < maxPage) {
            maxPage = pageCount + 1
        }
    
        if (maxPage - startPage !== noOfPagesNos && maxPage > noOfPagesNos) {
            startPage = maxPage - noOfPagesNos;
        }
    
        let paginationInfo = [];
    
        for (let i = startPage; i < maxPage; i++) {        
            paginationInfo.push({
                number: i,
                url: getPageNumberPath(i, basePath),
                isCurrent: currentPage === i
            });
        }
    
        return paginationInfo;
    };
    
    export const Pagination = ({ pageInfo, basePath }) => {
        if (!pageInfo) 
            return null
    
        const { currentPage, pageCount } = pageInfo
    
        // Create URL path for previous and next buttons
        const prevPagePath = currentPage === 2 ? basePath : `${basePath}/page-${(currentPage - 1)}`
        const nextPagePath = `${basePath}/page-${(currentPage + 1)}`
        
        if (pageCount > 1) { 
            return (
                    <ol>
                        {currentPage > 1 ? 
                            <li>
                                <Link to={prevPagePath}>
                                    Go to previous page
                                </Link>
                            </li> : null}       
                        {getPaginationGroup(basePath, currentPage, pageCount).map((item, i) => {
                            return (
                                <li key={i}>
                                    <Link to={item.url} className={`${item.isCurrent ?  "is-current" : ""}`}>
                                        Go to page {item.number}
                                    </Link>
                                </li>
                            )
                        })}
                        {currentPage !== pageCount ?
                            <li>
                                <Link to={nextPagePath}>
                                    Go to next page
                                </Link>
                            </li> : null}
                    </ol>
            )
        }
        else {
            return null
        }
      }
    
    Pagination.propTypes = {
        pageInfo: PropTypes.object,
        basePath: PropTypes.string
    }
    
    export default Pagination;
    

    This component requires just two parameters:

    1. pageInfo: A page context object created when Gatsby generates the site pages. The object should contain two properties consisting of the current page the that is being viewed (currentPage) and total number of pages (pageCount).
    2. basePath: The parent URL of where the pagination component will reside. For example, if your listing page is "/customers", this will be the base path. The pagination component will then prefix this to construct URL's in the format of - "/customers/page-2".
  • You probably haven't noticed (and you'd be forgiven if this is the case!) that my site now has the ability to search through posts. This is a strange turn of events for me as I decided to remove search capability from my site many years ago as I didn't feel it added any benefits for the user. This became evident from Google Analytics stats where searches never hit high enough numbers to warrant having it. The numbers don't lie!

    So what caused this turnaround?

    I've noticed that I'm regularly referring back through posts to refresh myself on things I've done in the past and to find solutions to issues I know I've previously written about. Having a search would make trawling through my few hundred posts a lot easier. So this is more of a personal requirement than commercial. But there is an exciting aspect to this as well - experimenting with Algolia. Using Algolia search is something I've been meaning to look into for a long time and integrating with GatbsyJS.

    The thought of having the good ol' magnifying glass back in the navigation makes me nostalgic!

    Note: In this post, I won't be covering the basic Algolia setup or the plugins needed to install as there is already a great wealth of information online. Check out my "Useful Links" section at the end of the post.

    Basic Setup

    Integrating Algolia into GatbsyJS was relatively straight-forward due to the wealth of information that others have already written and also the plugins themselves. The plugins make light work of rendering search results quickly allowing enough customisations to the HTML markup for easy implementation within any site. By default, the plugins contain the following components:

    • InstantSearch
    • SearchBox
    • Hits
    import algoliasearch from 'algoliasearch/lite';
    import PropTypes from 'prop-types';
    import { Link } from 'gatsby';
    import { InstantSearch, Hits, Highlight, SearchBox } from 'react-instantsearch-dom';
    import React from 'react';
    
    // Get API keys from the environment file.
    const appId = process.env.GATSBY_ALGOLIA_APP_ID;
    const searchKey = process.env.GATSBY_ALGOLIA_SEARCH_KEY;
    const searchClient = algoliasearch(appId, searchKey);
    
    const SearchPage = () => (
      <InstantSearch
        searchClient={searchClient}
        indexName={process.env.GATSBY_ALGOLIA_INDEX_NAME}
      >
        <SearchBox />
        <Hits hitComponent={Hit} />
      </InstantSearch>
    );
    
    function Hit(props) {
      return (
        <article className="hentry post">
          <h3 className="entry-title">
            <Link to={props.hit.fields.slug}>
              <Highlight attribute="title" hit={props.hit} tagName="mark" />
            </Link>
          </h3>
          <div className="entry-meta">
            <span className="read-time">{props.hit.fields.readingTime.text}</span>
          </div>
          <p className="entry-content">
            <Highlight hit={props.hit} attribute="summary" tagName="mark" />
          </p>
        </article>
      );
    }
    
    Hit.propTypes = {
      hit: PropTypes.object.isRequired,
    };
    
    export default SearchPage;
    

    The InstantSearch is the core component that directly interacts with Algolia's API and takes in two properties, "searchClient" and "indexName" containing the Application ID and Search Key that is acquired from the Algolia account setup. This component contains two child components, SearchBox is the search textbox and Hits that displays results from the search query.

    It is the Hits component where we can customise the HTML with our own markup by using it's "hitComponent" attribute. In my case, I created a function to generate HTML where I access the properties from the search index. What's really cool is here is we have the ability to also highlight our search term where they may occur in the results by using the Highlight component (also provided by the Algolia plugin) and adding a "tagName" attribute.

    Removing The SearchBox Component

    The standard implementation may not suit all scenarios as you may want a search term to be sent to the InstantSearch component differently. For example, it could be from a custom search textbox or (as in my case) read from a query-string parameter. It wasn't until I started delving further into the standard setup I realised you cannot just remove the SearchBox component and pass a value directly, but there is a workaround.

    I have expanded upon the code-snippet, above, to demonstrate how my search page works...

    import algoliasearch from 'algoliasearch/lite';
    import PropTypes from 'prop-types';
    import { Link } from 'gatsby';
    import { InstantSearch, Hits, Highlight, connectSearchBox } from 'react-instantsearch-dom';
    import Layout from "../components/global/layout";
    import React, { Component } from "react";
    
    // Get API keys from the environment file.
    const appId = process.env.GATSBY_ALGOLIA_APP_ID;
    const searchKey = process.env.GATSBY_ALGOLIA_SEARCH_KEY;
    const searchClient = algoliasearch(appId, searchKey);
    const VirtualSearchBox = connectSearchBox(() => <span />);
    
    class SearchPage extends Component { 
      state = {
        searchState: {
          query: '',
        },
      };
    
      componentDidMount() {   
        // Get "term" query string parameter value.
        let search = window.location.search;
        let params = new URLSearchParams(search);
        let searchTerm = params.get("term");
    
        // Send the query string value to a "searchState" object used by Algolia.
        this.setState(state => ({
          searchState: {
            ...state.searchState,
            query: searchTerm,
          },
        }));
     }
    
      render() {
          // Default "instantSearch" HTML to prompt user to enter a search term.
          var instantSearch = null;
          
          // If there is a search term, utilise Algolia's instant search.
          if (this.state.searchState.query) {
            instantSearch = <div className="entry-content">
                              <h2>You've searched for "{this.state.searchState.query}".</h2>
                              <div className="post-list archives-list">
                              <InstantSearch
                                  searchClient={searchClient}
                                  indexName={process.env.GATSBY_ALGOLIA_INDEX_NAME}
                                  searchState={this.state.searchState}
                                >
                                  <VirtualSearchBox />
                                  <Hits hitComponent={Hit} />
                                </InstantSearch>  
                              </div>
                            </div>
          }
          else {
            instantSearch = <div className="entry-content">
                              <h2>You haven't entered a search term.</h2>
                              <p>Carry out a search by clicking the <em>magnifying glass</em> in the navigation.</p>
                            </div>
          }
    
          return (
            <Layout>
              <header className="page-header">
                <h1>Search</h1>
                <p>Search the knowledge-base...</p>
              </header>
              <div id="primary" className="content-area">
                <div id="content" className="site-content" role="main">
                    <div className="layout-fixed">
                        <article className="page hentry">
                          {instantSearch}
                        </article>
                    </div>
                </div>
              </div>
          </Layout>
        )
      }
    }
    
    function Hit(props) {
      return (
        <article className="hentry post">
          <h3 className="entry-title">
            <Link to={props.hit.fields.slug}>
              <Highlight attribute="title" hit={props.hit} tagName="mark" />
            </Link>
          </h3>
          <div className="entry-meta">
            <span className="read-time">{props.hit.fields.readingTime.text}</span>
          </div>
          <p className="entry-content">
            <Highlight hit={props.hit} attribute="summary" tagName="mark" />
          </p>
        </article>
      );
    }
    
    Hit.propTypes = {
      hit: PropTypes.object.isRequired,
    };
    
    export default SearchPage
    

    My code is reading from a query-string value and passing that to a "searchState". The searchState object is created by React InstantSearch internally. Every widget inside the library has its own way of updating it. It contains parameters on the type of search that should be performed, such as query, sorting and pagination, to name a few. All we're interested in doing is updating the query parameter of this object with our search term.

    If the query parameter from the "searchState" object is empty, render search results, otherwise, display a message stating a search term is required.

    One thing to notice is the SearchBox has been replaced with a VirtualSearchBox, which uses the connector of the search box to create a virtual widget - in our case an empty span tag. This will link the InstantSearch component with the query. Having some form of search box component is compulsory.

    Conclusion

    I prefer not to use the out-of-the-box search box component as I can potentially save requests to Algolia's API, as searches aren't being made on the fly as a user enters a search term. This is the plugins default behaviour.

    Passing a search term through a query-string may come across as a little backwards, especially when it's rather nice to see search results change before your eyes as you type letter-by-letter. However, this approach misses one key element: Tracking in Google Analytics. Even though I will be primary the person making the most use of my site search, it'll be interesting to see who else uses it and what search keywords are used.

    Useful Links

  • I’ll be the first to admit that I very rarely (if at all!) assign a nice pretty share image to any post that gets shared on social networks. Maybe it’s because I hardly post what I write to social media in the first place! :-) Nevertheless, this isn’t the right attitude. If I am really going to do this, then the whole process needs to be quick and render a share image that sets the tone before that will hopefully entice a potential reader to click on my post.

    I started delving into how my favourite developer site, dev.to, manages to create these really simple text-based share images dynamically. They have a pretty good setup as they’ve somehow managed to generate a share image that contains relevant post related information perfectly, such as:

    • Post title
    • Date
    • Author
    • Related Tech Stack Icons

    For those who are nosey as I and want to know how dev.to undertakes such functionality, they have kindly written the following post - How dev.to dynamically generates social images.

    Since my website is built using the Gatsby framework, I prefer to use a local process to dynamically generate a social image without the need to rely on another third-party service. What's the point in using a third-party service to do everything for you when it’s more fun to build something yourself!

    I had envisaged implementing a process that will allow me to pass in the URL of my blog posts to a script, which in turn will render a social image containing basic information about a blog post.

    Intro Into Puppeteer

    Whilst doing some Googling, one tool kept cropping up in different forms and uses - Puppeteer. Puppeteer is a Node.js library maintained by Google Chrome’s development team and enables us to control any Chrome Dev-Tools based browser through scripts. These scripts can programmatically execute a variety of actions that you would generally do in a browser.

    To give you a bit of an insight into the actions Puppeteer can carry out, check out this Github repo. Here you can see Puppeteer is a tool for testing, scraping and automating tasks on web pages. It’s a very useful tool. The only part I spent most of my time understanding was its webpage screenshot feature.

    To use Puppeteer, you will first need to install the library package in which two options are available:

    • Puppeteer Core
    • Puppeteer

    Puppeteer Core is the more lighter-weight package that can interact with any Dev-Tool based browser you already have installed.

    npm install puppeteer-core
    

    You then have the full package that also installs the most recent version of Chromium within the node_modules directory of your project.

    npm install puppeteer
    

    I opted for the full package just to ensure I have the most compatible version of Chromium for running Puppeteer.

    Puppeteer Webpage Screenshot Script

    Now that we have Puppeteer installed, I wrote a script and added it to the root of my Gatsby site. The script carries out the following:

    • Accepts a single argument containing the URL of a webpage. This will be the page containing information about my blog post in a share format - all will become clear in the next section.
    • Approximately screenshot a cropped version of the webpage. In this case 840px x 420px - the exact size of my share image.
    • Use the page name in the URL as the image file name.
    • Store the screenshot in my "Social Share” media directory.
    const puppeteer = require('puppeteer');
    
    // If an argument is not provided containing a website URL, end the task.
    if (process.argv.length !== 3) {
      console.log("Please provide a single argument containing a website URL.");
      return;
    }
    
    const pageUrl = process.argv[2];
    
    const options = {
        path: `./static/media/Blog/Social Share/${pageUrl.substring(pageUrl.lastIndexOf('/') + 1)}.jpg`,
        fullPage: false,
        clip: {
          x: 0,
          y: 0,
          width: 840,
          height: 420
        }
      };
      
      (async () => {
        const browser = await puppeteer.launch({headless: false});
        const page = await browser.newPage()
        await page.setViewport({ width: 1280, height: 800, deviceScaleFactor: 1.5 })
        await page.goto(pageUrl)
        await page.screenshot(options)
        await browser.close()
      })(); 
    

    The script can be run as so:

    node puppeteer-screenshot.js http://localhost:8000/socialcard/Blog/2020/07/25/Using-Instagram-API-To-Output-Profile-Photos-In-ASPNET-2020-Edition
    

    I made an addition to my Gatsby project that generated a social share page for every blog post where the URL path was prefixed with /socialcard. These share pages will only be generated when in development mode.

    Social Share Page

    Now that we have our Puppeteer script, all that needs to be accomplished is to create a nice looking visual for Puppeteer to convert into an image. I wanted some form of automation where blog post information was automatically populated.

    I’m starting off with a very simple layout taking some inspiration from dev.to and outputting the following information:

    • Title
    • Date
    • Tags
    • Read time

    Working with HTML and CSS isn’t exactly my forte. Luckily for me, I just needed to do enough to make the share image look presentable.

    Social Card Page

    You can view the HTML and CSS on JSFiddle. Feel free to update and make it better! If you do make any improvements, update the JSFiddle and let me know!

    Next Steps

    I plan on adding some additional functionality allowing a blog post teaser image (if one is added) to be used as a background and make things look a little more interesting. At the moment the share image is very plain. As you can tell, I keep things really simple as design isn’t my strongest area. :-)

    If all goes to plan, when I share this post to Twitter you should see my newly generated share image.

  • I’ve been doing a little research into how I can make posts written in markdown more suited for my needs and decided to use this opportunity to develop my own Gatsby Markdown plugin. Ever since I moved to Gatsby, making my own Markdown plugin has been on my todo list as I wanted to see how I could render slightly different HTML markup based on the requirements of my blog post content.

    As this is my first markdown plugin, I thought it best to start small and tackle bug-bear of mine - making external links automatically open in a new window. From what I have looked online, some have suggested to just add an HTML anchor tag to the markdown as you will then have the ability to apply all attributes you’d want - including target. I’ll quote my previous post about aligning images in markdown and why I’m not keen on mixing HTML with markdown:

    HTML can be mingled alongside the markdown syntax... I wouldn't recommend this from a maintainability perspective. Markdown is platform-agnostic so your content is not tied to a specific platform. By adding HTML to markdown, you're instantly sacrificing the portability of your content.

    Setup

    We will need to create a local Gatsby plugin, which I’ve named gatsby-remark-auto-link-new-window. Ugly name... maybe you can come up with something more imaginative. :-)

    To register this to your Gatsby project, you will need start of with the following:

    • Creating a plugin folder at the root of your project (if one hasn’t been created already).
    • Add a new folder based on the name of our plugin, in this case - /plugins/gatsby-remark-auto-link-new-window.
    • Every plugin consists of two files:
      • index.js - where the plugin code to carry out our functionality will reside.
      • package.json - contains the details of our plugin, such as name, description, dependencies etc. For the moment this can just contain an empty JSON object {}. If we were to publish our plugin, this will need to be completed in its entirety.

    Now that we have our bare-bones structure, we need to register our local plugin by adding a reference to the gatsby-config.js file. Since this is a plugin to do with transforming markdown, the reference will be added inside the 'gatsby-transformer-remark options:

    {
      // ...
      resolve: 'gatsby-transformer-remark',
        options: {
          plugins: [        
            {
              resolve: 'gatsby-remark-embed-gist',
              options: {
                username: 'SurinderBhomra',
              },
            },
            {
              resolve: 'gatsby-remark-auto-link-new-window',
              options: {},
            },
            'gatsby-remark-prismjs',
          ],
        },
      // ...
    }
    

    For the moment, I’ve left the options field empty as we currently have no settings to pass to our plugin. This is something I will show in another blog post.

    To make sure we have registered our plugin with no errors, we need run our build using the gatsby clean && gatsby develop command. This command will always need to be run after every change made to the plugin. By adding gatsby clean, we ensure the build clears out all the previously built files prior to the next build process.

    Rewriting Links In Markdown

    As the plugin is relatively straight-forward, let’s go straight into the code that will be added to our index.js file.

    const visit = require("unist-util-visit")
    
    module.exports = ({ markdownAST }, pluginOptions) => {
      visit(markdownAST, "link", node => {
        // Check if link is external by checking if the "url" attribute starts with http.
        if (node.url.startsWith("http")) {
          if (!node.data) {
            // hProperties refers to the HTML attributes of the node in question.
            // Ensure this object is added to the node.
            node.data = { hProperties: {} };
          }
          
          // Assign the 'target' attribute.
          node.data.hProperties = Object.assign({}, node.data.hProperties, {
            target: "_blank",
          });
        }
      })
    
      return markdownAST
    }
    

    As you can see, I want to target all markdown link nodes and depending on the contents of the url property we will perform a custom transformation. If the url property starts with an "http" we will then add a new attribute, "target" using hProperties. hProperties refers to the HTML attributes of the targeted node.

    To see the changes take effect, we will need to re-run gatsby clean && gatsby develop.

    Now that we have understood the basics, we can beef up our plugin by adding some more functionality, such as plugin options. But that's for another post.

  • Published on
    -
    1 min read

    Aligning Images In Markdown

    Every post on this site is written in markdown since successfully moving over to GatsbyJS. Overall, the transition has been painless and found that writing blog posts using the markdown syntax is a lot more efficient than using a conventional WYSIWYG editor. I never noticed until making the move to markdown how fiddly those editors were as you sometimes needed to clean the generated markup at HTML level.

    Of course, all the efficiency of markdown does come at a minor cost in terms of flexibility. Out of the minor limitations, there was one I couldn't let pass. I needed to find a way to position images left, right and centre as majority of my previous posts have been formatted in this way. When going through the conversion process from HTML to markdown, all my posts were somewhat messed up and images were rendered 100% width.

    HTML can be mingled alongside the markdown syntax, so I do have an option to use the image tag and append styling. I wouldn't recommend this from a maintainability perspective. Markdown is platform-agnostic so your content is not tied to a specific platform. By adding HTML to markdown, you're instantly sacrificing the portability of your content.

    I found a more suitable approach would be to handle the image positioning by appending a hashed value to the end of the image URL. For example, #left, #right, or #centre. We can at CSS level target the src attribute of the image and position the image along with any additional styling based on the hashed value. Very neat!

    img[src*='#left'] {
    float: left;
    margin: 10px 10px 10px 0;
    }
    
    img[src*='#center'] {
    display: block;
    margin: 0 auto;
    }
    
    img[src*='#right'] {
    float: right;
    margin: 10px 0 10px 10px;
    }
    

    Being someone who doesn’t delve into front-end coding techniques as much as I used to, I am amazed at the type of things you can do within CSS. I’ve obviously come late to the more advanced CSS selectors party.

  • If you’re seeing this post, then this means I have fully made the transition to a static-generated website architecture using GatsbyJS. I started this process late December last year but then started taking it seriously into the new year. It’s been a learning process getting to grips with a new framework as well as a big jump for me and my site.

    Why has it been a big jump?

    Everything is static. I have downsized my website footprint exponentially. All 250+ blog posts have been migrated into markdown files, so from now on, I will be writing in markdown and (with the help of Netlify) pushing new content by a simple git commit. Until now, I have always had a website that used server-side frameworks that stored all my posts in a database. It’s quite scary moving to a framework that feels quite unnatural to how I would normally build sites and the word “static” when used in relation to a website reminds me of a bygone era.

    Process of Moving To Netlify

    I was pleasantly surprised by how easy the transition to Netlify was. There is a vast amount of resources available that makes for good reading before making the switch to live. After linking my website Bitbucket repository to a site, the only things left to do to make it live were the following:

    • Upload a _redirects file, listing out any redirects you require Netlify to handle. For GatsbyJS sites, this will need to be added to the /static directory.
    • Setup Environment variables to allow the application to easily switch between development and production states. For example, my robots.txt is set to be indexable when only in production mode.
    • Add CNAME records to your existing domain that point to your Netlify domain. For example, surindersite.netlify.com.
    • Issue a free Let’s Encrypt SSL certificate, which is easily done within the account Domain settings.

    Post live, the only thing that stumped me was the Netlify domain didn’t automatically redirect to my custom domain. This is something I thought Netlify would automatically handle once the domain records were updated. To get around this, an explicit domain 301 redirect needs to be added to your _redirects file.

    # Domain Redirect
    https://surinderbhomra.netlify.com/*     https://www.surinderbhomra.com/:splat    301!
    

    New Publishing Process

    Before making the switchover, I had to carry out some practice runs on how I would be updating my website just to be sure I could live with the new way of adding content. The process is now the following:

    1. Use “content/posts” branch to add a new blog post.
    2. Create a new .md file that consists of the date and slug. In my case, all my markdown files are named "2010-04-02---My-New-Post.md".
    3. Ensure all categories and tags in the markdown frontmatter is named correctly. This is an important step to ensure no unnecessary new categories or tags are created.
    4. Add any images used in the post to the site. The images should reference Imagekit.io.
    5. Check over the post locally.
    6. Push to master branch and let Netlify carry out the rest.

    Out of all the steps, I have only found steps 3 and 4 to require a little effort when compared to using a CMS platform, as previously, I could select from a predefined list of categories and upload images directly. Not a deal-breaker.

    Next Steps

    I had a tight deadline to ensure I made the move to Netlify before my current hosting renews for another year and still have quite a bit of improvement to make. Have you seen my Google Lighthouse score!?! It’s shockingly bad due to using the same HTML markup and CSS from my old site. I focused my efforts cramming in all the functionality to mimic how my site used to work and efficiencies in keeping build times to Netlify low.

    First thing on the list - rebuild website templates from the ground up.

  • For the Gatsby version of my website, currently in development, I am serving all my images from Imagekit.io - a global image CDN. The reasons for doing this is so I will have the ultimate flexibility in how images are used within my site, which didn’t necessarily fit with what Gatsby has to offer especially when it came to how I wanted to position images within blog post content served from markdown files.

    As I understand it, Gatsby Image has two methods of responsively resizing images:

    1. Fixed: Images that have a fixed width and height.
    2. Fluid: Images that stretch across a fluid container.

    In my blog posts, I like to align my images (just take look at my post about my time in the Maldives) as it helps break the post up a bit. I won’t be able to achieve that look by the options provided in Gatsby. It’ll look all a little bit too stacked. The only option is to serve my images from Imagekit.io, which in the grand scheme isn’t a bad idea. I get the benefit of being able to transform images on the fly, optimisation (that can be customised through Imagekit.io dashboard) and fast delivery through its content-delivery network.

    To meet my image requirements, I decided to develop a custom responsive image component that will perform the following:

    • Lazyload image when visible in viewport.
    • Ability to parse an array “srcset" sizes.
    • Set a default image width.
    • Render the image on page load in low resolution.

    React Visibility Sensor

    The component requires the use of "react-visibility-sensor” plugin to mimic the lazy loading functionality. The plugin notifies you when a component enters and exits the viewport. In our case, we only want the sensor to run once an image enters the viewport. By default, the sensor is always fired every time a block enters and exits the viewport, causing our image to constantly alternate between the small and large versions - something we don't want.

    Thanks for a useful post by Mark Oskon, he provided a solution that extends upon the react-visibility-sensor plugin and allows us to turn off the sensor after the first reveal. I ported the code from Mark's solution in a newly created component housed in "/core/visibility-sensor.js", which I then reference into my LazyloadImage component:

    import React, { Component } from "react";
    import PropTypes from "prop-types";
    import VSensor from "react-visibility-sensor";
    
    class VisibilitySensor extends Component {
      state = {
        active: true
      };
    
      render() {
        const { active } = this.state;
        const { once, children, ...theRest } = this.props;
        return (
          <VSensor
            active={active}
            onChange={isVisible =>
              once &&
              isVisible &&
              this.setState({ active: false })
            }
            {...theRest}
          >
            {({ isVisible }) => children({ isVisible })}
          </VSensor>
        );
      }
    }
    
    VisibilitySensor.propTypes = {
      once: PropTypes.bool,
      children: PropTypes.func.isRequired
    };
    
    VisibilitySensor.defaultProps = {
      once: false
    };
    
    export default VisibilitySensor;
    

    LazyloadImage Component

    import PropTypes from "prop-types";
    import React, { Component } from "react";
    import VisibilitySensor from "../core/visibility-sensor"
    
    class LazyloadImage extends Component {
        render() {
          let srcSetAttributeValue = "";
          let sanitiseImageSrc = this.props.src.replace(" ", "%20");
    
          // Iterate through the array of values from the "srcsetSizes" array property.
          if (this.props.srcsetSizes !== undefined && this.props.srcsetSizes.length > 0) {
            for (let i = 0; i < this.props.srcsetSizes.length; i++) {
              srcSetAttributeValue += `${sanitiseImageSrc}?tr=w-${this.props.srcsetSizes[i].imageWidth} ${this.props.srcsetSizes[i].viewPortWidth}w`;
    
              if (this.props.srcsetSizes.length - 1 !== i) {
                srcSetAttributeValue += ", ";
              }
            }
          }
    
          return (
              <VisibilitySensor key={sanitiseImageSrc} delayedCall={true} partialVisibility={true} once>
                {({isVisible}) =>
                <>
                  {isVisible ? 
                    <img src={`${sanitiseImageSrc}?tr=w-${this.props.widthPx}`} 
                          alt={this.props.alt}
                          sizes={this.props.sizes}
                          srcSet={srcSetAttributeValue} /> : 
                    <img src={`${sanitiseImageSrc}?tr=w-${this.props.defaultWidthPx}`} 
                          alt={this.props.alt} />}
                  </>
                }
              </VisibilitySensor>
          )
        }
    }
    
    LazyloadImage.propTypes = {
      alt: PropTypes.string,
      defaultWidthPx: PropTypes.number,
      sizes: PropTypes.string,
      src: PropTypes.string,
      srcsetSizes: PropTypes.arrayOf(
        PropTypes.shape({
          imageWidth: PropTypes.number,
          viewPortWidth: PropTypes.number
        })
      ),
      widthPx: PropTypes.number
    }
    
    LazyloadImage.defaultProps = {
      alt: ``,
      defaultWidthPx: 50,
      sizes: `50vw`,
      src: ``,
      widthPx: 50
    }
    
    export default LazyloadImage
    

    Component In Use

    The example below shows the LazyloadImage component used to serve a logo that will serve a different sized image with the following widths - 400, 300 and 200.

    <LazyloadImage 
                    src="https://ik.imagekit.io/surinderbhomra/Pages/logo-me.jpg" 
                    widthPx={400} 
                    srcsetSizes={[{ imageWidth: 400, viewPortWidth: 992 }, { imageWidth: 300, viewPortWidth: 768 }, { imageWidth: 200, viewPortWidth: 500 }]}
                    alt="Surinder Logo" />
    

    Useful Links

    https://alligator.io/react/components-viewport-react-visibility-sensor/ https://imagekit.io/blog/lazy-loading-images-complete-guide/ https://www.sitepoint.com/how-to-build-responsive-images-with-srcset/

  • There will be times where you will want to customise the slug based on fields from your markdown file. In my case, I wanted all my blog post URL's in the following format: /Blog/yyyy/MM/dd/Blog-Post-Title. There are two ways of doing this:

    1. Enter the full slug using a “slug” field within your markdown file.
    2. Use the onCreateNode() function found in the gatsby-node.js file to dynamically generate the slug.

    My preference would be option 2 as it gives us the flexibility to modify the slug structure in one place when required. If for some reason we had to update our slug structure at a later date, it would be very time consuming (depending on how many markdown files you have) to update the slug field within each markdown file if we went ahead with option 1.

    This post is suited for those who are storing their content using markdown files. I don’t think you will get much benefit if your Gatsby site is linked to a headless CMS, as the slugs are automatically generated within the platform.

    The onCreateNode() Function

    This function is called whenever a node is created or updated, which makes it the most ideal place to add the functionality we want to perform. It is found in the gatsby-node.js file

    What we need to do is retrieve the fields we would like to form part of our slug by accessing the nodes frontmatter. In our case, all we require is two fields:

    1. Post Date
    2. Slug
    exports.onCreateNode = ({ node, actions, getNode }) => {
        const { createNodeField } = actions
      
        if (node.internal.type === `MarkdownRemark`) {
          const relativeFilePath = createFilePath({ node, getNode, trailingSlash: false });
          const postDate = moment(node.frontmatter.date); // Use moment.js to easily change date format.
          const url = `/Blog/${postDate.format("YYYY/MM/DD")}${node.frontmatter.slug}`;
    
          createNodeField({
            name: `slug`,
            node,
            value: url,
          });
        }
      }
    

    After making this change, you will need to re-run the gatsby develop command.