It's Easy to Build: Custom docs project | Part 1 - MD to HTML
In this first part of the series - It's Easy to Build: Custom docs project, we'll learn how to convert our markdown text to an HTML code using Ruby.
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Hey there, my blog has been in a stale model for a long time as I wrote my last blog post on 19th December 2020. So it is a long time. I was busy lurking over various places as I'm dirtying my hands in Blockchain. I hope you all are doing good and are standing firm during these testing times of COVID-19.
Introduction
Recently, I had a task to write my documentation for all my self-projects in a separate place other than GitHub's README. To accomplish this, I came across a few open-source projects like Slate Docs, Docusaurus, to name a few. They are useful in their ways, but they didn't fit my expectations. I also wanted my docs in my desityle library, which is impossible to achieve from these projects.
So I decided to build my own docs project, and it's live at Drabkirn Docs, and it's open-source. It took me a couple of days to learn things and complete this project, and in this tutorial series, I'll share my learnings as a beginner-friendly way.
For developers, writing docs is super-easy when we write it in markdown
syntax, as writing in HTML
will be a harrowing experience. That's why GitHub's README file looks simple clean with such a less code written in README.md
file.
For this problem statement, I came up with this solution:
- I write my docs content in a markdown(MD) file.
- The app converts the above MD file content to an HTML code.
- We configure our app to include our desityle library, add our custom SEO tags and custom elements generation.
- We then inject this HTML code to our
index.html
file. - Then build our code to minify content and push to production.
In this part 1 tutorial of this series, we'll take a very first small step to learn how to convert a markdown code to an HTML code and inject this HTML code into an HTML file. To accomplish this, we'll use the Ruby language and redcarpet
gem.
Getting Started
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For this tutorial, you'll need Ruby installed in your machine. You can use this GoRails guide to setup ruby.
-
First, create a new folder and
cd
into it:$ mkdir mdtohtml $ cd mdtohtml
-
Install the
redcarpet
gem:- First, you need to create a file named
Gemfile
$ touch Gemfile
- Then add
redcarpet
gem to this file:# Gemfile source 'https://rubygems.org' git_source(:github) { |repo| "https://github.com/#{repo}.git" } ruby '2.6.5' gem 'redcarpet', '~> 3.5'
- First, you need to create a file named
-
Install the dependencies:
$ bundle i
-
Now create three files:
config.rb
: We'll write our ruby code logic in this filehello.md
: We'll write our markdown text in this fileinput.html
: The output of the converted markdown text which will be injected in this file.$ touch config.rb $ touch hello.md $ touch input.html
Codebase:
Let's start writing the code:
-
First, open up your favorite editor and write a sample text in
hello.md
file# Hello This is just a hello file [Link](https://google.com) > This is a blockquote *This is em* **This is bold** ## This is header 2 ### This is header 3
-
Now, open the
config.rb
file and write our logic:# First, we need to import `redcarpet` library require 'redcarpet' # Now let us import our `hello.md` file and `index.html` file: ## For `hello.md`, we only give READ permission, so that we don't mess ## up with our markdown file ## For `index.html` we'll give RE-WRITE permission, that means ## Everytime the code parses, it will clean this file and re-enter code hello_md_text_file = File.open('./hello.md', 'r') index_html_file = File.open('./index.html', 'w+') # Now we'll initialize Redcarpet: ## For now, we'll not use any options, we'll keep this simple md_renderer_options = {} md_extensions = {} md_renderer = Redcarpet::Render::HTML.new(md_renderer_options) markdown = Redcarpet::Markdown.new(md_renderer, md_extensions) # Read the contents of `hello.md` file and put it in `md_text` variable md_text = hello_md_text_file.read # convert MD to HTML, put it in `md_to_html_text` variable md_to_html_text = markdown.render(md_text) # Now inject this HTML content in `index.html` file index_html_file.puts md_to_html_text # Now, close the files hello_md_text_file.close index_html_file.close
- This was simple; everything is explained in the code comments above, and to summarize:
- We first import the
redcarpet
gem - Then we import the
hello.md
andindex.html
files - We'll then initialize
redcarpet
with no options to keep things simple. - We then convert our markdown text to HTML code and inject this code to
index.html
file - Finally, we close both the files as a good practice.
-
Running the script:
- Run the script by using this command:
$ ruby config.rb
- Run the script by using this command:
-
Now, in the
index.html
file, you'll see the MD to HTML converted code.
Testing it:
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We finished with the coding part, now let's test it out:
-
Most of the modern machines have
python
installed, so we'll useSimpleHTTPServer
to fire up our server, you can use any server:$ python -m SimpleHTTPServer 3000 # Or any other web server
-
Now, visit
localhost:3000
or$YOUR_IP:3000
, to the see yourindex.html
file. It looks like this:
-
To summarize, here is how the workflow will work from now:
- You keep adding more content to
hello.md
file - Then, run the script:
$ ruby config.rb
- The above command will update the
index.html
file. - Now, refresh your webpage, and you'll see the updated markdown to HTML code.
- You keep adding more content to
Summary and conclusion
Let's take a quick look at what we learned today:
- First of all, I introduced myself, so don't forget to connect with me at Twitter or elsewhere.
- Next, we described and understood our problem statement.
- We then outlined a solution to our problem statement, and this tutorial is a partial solution to our big problem statement.
- Then we saw what the prerequisites are, and we also set up and understood our file structure for this tutorial.
- We then wrote our ruby code logic to solve our problem, i.e., converting a markdown text to HTML code and injecting it into an
index.html
file. - Next, we tested our
index.html
file by firing up a server. - We then defined what our workflow will be for adding more content to our
hello.md
file. - Finally, we took a quick look at this very summary...
That's it and Let there be the end. 🙏