gh-action-data-scraping VS scrape-hacker-news-by-domain

i do this as a demo: https://github.com/swyxio/gh-action-data-scraping

but conveniently it also serves as a way to track the downtime of github actions, which used to be bad but seems to be fine the last couple months: https://github.com/swyxio/gh-action-data-scraping/assets/676...

Yeah I have a bunch of these using pretty-printed JSON - here's one that scrapes Hacker News for mentions of my site, for example: https://github.com/simonw/scrape-hacker-news-by-domain/blob/...

Git is a key technology in this approach, because the value you get out of this form of scraping is the commit history - it's a way of turning a static source of information into a record of how that information changed over time.

I think it's fine to use the term "scraping" to refer to downloading a JSON file.

These days an increasing number of websites work by serving up JSON which is then turned into HTML by a client-side JavaScript app. The JSON often isn't a formally documented API, but you can grab it directly to avoid the extra step of processing the HTML.

I do run Git scrapers that process HTML as well. A couple of examples:

scrape-san-mateo-fire-dispatch https://github.com/simonw/scrape-san-mateo-fire-dispatch scrapes the HTML from http://www.firedispatch.com/iPhoneActiveIncident.asp?Agency=... and records both the original HTML and converted JSON in the repository.

scrape-hacker-news-by-domain https://github.com/simonw/scrape-hacker-news-by-domain uses my https://shot-scraper.datasette.io/ browser automation tool to convert an HTML page on Hacker News into JSON and save that to the repo. I wrote more about how that works here: https://simonwillison.net/2022/Dec/2/datasette-write-api/

I have a neat Hacker News scraping setup that I'm really pleased with.

The problem: I want to know when content from one of my sites is submitted to Hacker News, and keep track of the points and comments over time. I also want to be alerted when it happens.

Solution: https://github.com/simonw/scrape-hacker-news-by-domain/

This repo does a LOT of things.

It's an implementation of my Git scraping pattern - https://simonwillison.net/2020/Oct/9/git-scraping/ - in that it runs a script once an hour to check for more content.

It scrapes https://news.ycombinator.com/from?site=simonwillison.net (scraping the HTML because this particular feature isn't supported by the Hacker News API) using shot-scraper - a tool I built for command-line browser automation: https://shot-scraper.datasette.io/

The scraper works by running this JavaScript against the page and recording the resulting JSON to the Git repository: https://github.com/simonw/scrape-hacker-news-by-domain/blob/...

That solves the "monitor and record any changes" bit.

But... I want alerts when my content shows up.

I solve that using three more tools I built: https://datasette.io/ and https://datasette.io/plugins/datasette-atom and https://datasette.cloud/

This script here runs to push the latest scraped JSON to my SQLite database hosted using my in-development SaaS platform, Datasette Cloud: https://github.com/simonw/scrape-hacker-news-by-domain/blob/...

I defined this SQL view https://simon.datasette.cloud/data/hacker_news_posts_atom which shows the latest data in the format required by the datasette-atom plugin.

Which means I can subscribe to the resulting Atom feed (add .atom to that URL) in NetNewsWire and get alerted when my content shows up on Hacker News!

I wrote a bit more about how this all works here: https://simonwillison.net/2022/Dec/2/datasette-write-api/

I'm really pleased with the Hacker News scraping demo in this - it's an extension of the scraper I wrote back in March, using shot-scraper to execute JavaScript in headless Chrome and write the resulting JSON back to a Git repo: https://simonwillison.net/2022/Mar/14/scraping-web-pages-sho...

My new demo also then pipes that data up to Datasette using curl -X POST - this script here: https://github.com/simonw/scrape-hacker-news-by-domain/blob/...