News Repository As A Git Subtree

As mentioned in the section before, all three websites(feelpp.org, csmi.math.unistra.fr and www.cemosis.fr) that I mainly worked on have a folder _posts under its source code root directory. In this folder, all posts wrote in Markdown will be parsed by Jekyll to generate associated HTML page. What we want is figuring out a way to easily maintain these three folders. So here comes an idea that I put the contents in three folders into a single one folder always called _posts. As the name _posts is a mandatory of Jekyll's file structure. Now it contains three sub folders for each websites:

_posts

|-- csmi

|-- cemosis

|-- feelpp

Briefly I migrated all Markdown files from old _posts folders into appropriate sub folders.

The source code of website is managed by the famous version control tool called Git. As a result, I deleted three old _posts folders and untrack them in Git project tree.

Now the question is: how to integrate this new, merged _posts folder into each website. With Git, we get two choices: one is the Git Submodule and the other is Git subtree.

They all have similar functionality: keep an isolated Git repository under another Git repository. In this way, the news folder can be shared within three websites.

We chose Git subtree as our final decision, because Git submodule has many downsides handling a repository that going to be frequently updated. Unlike Git submodule, it stores the files in the main repository(the website source code repositories) and merging changes directly to that repository. Which means Git subtree will copy the new _posts folder from its original news repository on Github under each main repository, then Git will track on extra these local copies.

As the news subtree repository is stored locally in each main repository, the next important step is to keep them up to date with their origin: news repository itself hosted on Github. This can be achieved by using Github's Webhook service, which will be introduced in the next chapter of this report.

Integrate news repository in three websites' code bases

The news repository itself on Github:

All three _posts directories are in fact local copies of original news repository.