Statement

Slogan version

$$\sigma = \pi + \lambda$$

$\sigma$	$\pi$	$\lambda$
“sum”	“product”	“limit”
universe	nonempty	universe
complement		complement
countable union	finite intersection	disjoint countable union

A $\sigma$-algebra is a $\pi$-system and a $\lambda$-system, and vice versa.

Wiki version

A $\lambda$-system is a synonym of a Dykin system.

$$\mathcal{P} \subseteq \mathcal{D} \Longrightarrow \sigma(\mathcal{P}) \subseteq \mathcal{D}$$

Given a $\pi$-system contained in a $\lambda$-system. Then the $\sigma$-algebra generated by the $\pi$-system is also contained in the $\lambda$-system.

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Update: I suggest reading a newer tutorial for setting up your custom API server that works with GitHub Apps. The package maintainers suggest hosting your own API server.

Goal

To host an instance of Staticman v3 server on Heroku.

This post involves server-side setup of the commenting system. If you simply want to have a taste of this system on GitLab, you may try my demo GitLab Page.

I try to address some concerns about this API service in the introduction of this series to keep this page focused on the technical aspects of my customizations against staticman/dev branch.

Background

While making changes to a theme for a static site generator, I changed files under a Git submodule included in the repo for my blog. (e.g. themes/beautifulhugo) That’s ideal for local testing, but not for version control. As a result, I cloned the repo for the theme to a directory separate from the one for my bloge (say, ~/beautifulhugo), and commit the changes there, then performed a Git submodule update so as to make the workflow clean.

Background (TL;DR)

While setting up the new version of Staticman for my demo GitLab pages, I’ve read developers’ documentations, setup guide and some community blog posts so as to come up with my own guide. It’s originated and inspired from a variety of sources, and refined according to hours of testing. Consequently, despite the original intention to keep things simple, I’ve finally come up with a post with over a thousand words.

To pass my ideas in this post to visitors, it’s better that they have an overview of the contents before actually looking into the details. Therefore, a table of contents is nice-to-have feature for this blog.

Update: I suggest reading a newer tutorial.

To keep focused on the technical setup, please refer to the introduction of this series for the reasons of choosing Staticman and GitLab.

Goal

To set up unauthenticated commenting system on GitLab pages.

This post aims at providing a walkthrough to the GitLab repo setup. If you want to host your own Staticman API instance, you may refer to the next post in this series.

I put some “why” questions here so as to keep focus on the technical setup of the GitLab repo and the optional Staticman API server.

Why static blogs instead of dynamic ones?

• quicker loading time
• better reliability (can handle more request)
• no database needed
• greater control on content, styles and layout

Why static comments?

• allow feedback from visitors
• site owner owns the comment locally (unlike WordPress, Facebook, Disqus, etc)
  • no remote database needed, so no need to worry server errors from third-party commenting services.
  • greater control over the rendering of the comments (allow additional features such as Markdown syntax, and $\KaTeX$ support)
  • more accessible since static comments are incorporated as HTML elements into the post. No JavaScript is required to retrieve the comments, contrary to most third-party commenting services.

Before Staticman’s deployment, another commenting system called Pecosys was already available. However, it’s less convenient to handle visitor’s requests as emails.

Background

My churches are going green.

Problem

→ I downloaded a PDF from Haute-Garonne’s government site, filled in the form and saved it on a USB key. Then I printed it at a Konica Minolta bizhub photocopier yesterday.

Problem

I would like to submit Flying Grizzly’s form. I filled in every blanks and then I clicked the “submit” button below. I was greeted with a MISSING_REQUIRED_FIELDS error within a second.

{
    "success":false,
    "data":["replying_to"],
    "rawError":{
        "_smErrorCode":"MISSING_REQUIRED_FIELDS",
        "data":["replying_to"]
    },
    "errorCode":"MISSING_REQUIRED_FIELDS"
}

Discussion

The error code suggested that the form fields sent should be inspected.

Fixed issue #142

Two weeks ago, Google Webmasters complained about the broken urls in this blog’s Tags page. This was reported by Joakim Vivas as issue #142 half a year ago. Pascal had submitted pull request #165 to fix this. However, he self-closed his PR.

Since the last commit by Michael Romero, Beautiful Hugo’s owner, was five months ago, it seems that he has abandonned his project. Therefore, I used Kaushal Modi’s solution to fix this at commit ff536782.

Goal

To enable Chinese and Japanese input on (X)ubuntu 18.04 laptops .

My choices of input method

On my old Fujitsu laptop running Xubuntu, I’ve chosen Fcitx. This turns out to be a difficult choice when I install Rime.

Japanese input

Thanks to ひゃまだ, I’ve managed to switch between difference modes in Mozc.