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TIL Paginating through the GitHub GraphQL API with Python — (See also [Building a self-updating profile README for GitHub](https://simonwillison.net/2020/Jul/10/self-updating-profile-readme/) on my blog)
10th Jul 2020, 4 am
TIL Writing tests for the ASGI lifespan protocol with HTTPX — Uvicorn silently ignores exceptions that occur during startup against the ASGI lifespan protocol - see [starlette/issues/486](https://github.com/encode/starlette/issues/486).
29th Jun 2020, 4:13 pm
TIL Using LD_PRELOAD to run any version of SQLite with Python — I've been wanting to figure this out for ages. [This thread](https://news.ycombinator.com/item?id=23282684) on Hacker News plus [this Stackoverflow post](https://unix.stackexchange.com/questions/24811/changing-linked-library-for-a-given-executable-centos-6/24833#24833:) gave me some initial clues.
17th Jun 2020, 8:12 pm
TIL Asserting a dictionary is a subset of another dictionary — My [lazy approach to writing unit tests](https://simonwillison.net/2020/Feb/11/cheating-at-unit-tests-pytest-black/) means that sometimes I want to run an assertion against most (but not all) of a dictionary.
28th May 2020, 3:09 pm
TIL Introspecting Python function parameters — For https://github.com/simonw/datasette/issues/581 I want to be able to inspect a Python function to determine which named parameters it accepts and send only those arguments.
27th May 2020, 10:43 pm
TIL Adding project links to PyPI — I spotted a neat looking project links section on https://pypi.org/project/ExifReader/
11th May 2020, 4:33 pm
TIL Converting HTML and rich-text to Markdown — If you copy and paste from a web page - including a full table - into a GitHub issue comment GitHub converts it to the corresponding Markdown for you. Really quick way to construct Markdown tables.
9th May 2020, 6:19 pm
TIL Build the official Python documentation locally — First, checkout the cpython repo:
8th May 2020, 4:16 pm
TIL List all columns in a SQLite database — Here's a devious trick for listing ALL columns in a SQLite database, using a SQL query that generates another SQL query.
6th May 2020, 3:58 pm
TIL Use setup.py to install platform-specific dependencies — For [photos-to-sqlite](https://github.com/dogsheep/photos-to-sqlite) I needed to install `osxphotos` as a dependency, but only if the platform is macOS - it's not available for Linux.
5th May 2020, 9:14 pm
TIL Search across all loaded resources in Firefox — You can search for a string in any resource loaded by a page (including across HTML, JavaScript and CSS) in the Debugger pane by hitting Command+Shift+F.
5th May 2020, 6:38 pm
TIL Installing and upgrading Datasette plugins with pipx — If you installed `datasette` using `pipx install datasette` you can install additional plugins with `pipx inject` like so:
4th May 2020, 7:14 pm
TIL Constant-time comparison of strings in Node — When comparing secrets, passwords etc it's important to use a constant-time compare function to avoid timing attacks.
2nd May 2020, 2:18 am
TIL Accessing repository dependencies in the GitHub GraphQL API — [Access to a Repositories Dependency Graph](https://developer.github.com/v4/previews/#access-to-a-repositories-dependency-graph) describes a preview API for accessing GitHub repository dependencies.
30th Apr 2020, 9:46 pm
TIL Compile a new sqlite3 binary on Ubuntu — I wanted to try the `vacuum into` backup command that was released in SQLite3 3.27.0 [on 2019-02-07](https://www.sqlite.org/changes.html#version_3_27_0).
30th Apr 2020, 5:40 pm
TIL How to mock httpx using pytest-mock — I wrote this test to exercise some [httpx](https://pypi.org/project/httpx/) code today, using [pytest-mock](https://pypi.org/project/pytest-mock/).
29th Apr 2020, 5:49 pm
TIL Generated a summary of nested JSON data — I was trying to figure out the shape of the JSON object from https://github.com/simonw/coronavirus-data-gov-archive/blob/master/data_latest.json?raw=true - which is 3.2MB and heavily nested, so it's difficult to get a good feel for the shape.
29th Apr 2020, 1:07 am
TIL Session-scoped temporary directories in pytest — I habitually use the `tmpdir` fixture in pytest to get a temporary directory that will be cleaned up after each test, but that doesn't work with `scope="session"` - which can be used to ensure an expensive fixture is run only once per test session and the generated content is used for multiple tests.
27th Apr 2020, 3:47 am
TIL Fixing "compinit: insecure directories" error — Every time I opened a terminal on my new Mac running Catalina with zsh I got the following annoying error:
26th Apr 2020, 4:49 pm
TIL Restricting SSH connections to devices within a Tailscale network — I'm running an AWS Lightsail instance and I want to only be able to SSH to it from devices connected to my [Tailscale](https://tailscale.com/) network.
23rd Apr 2020, 2:21 pm
TIL Close terminal window on Ctrl+D for macOS — I always forget how to set this up. It's hidden in Preferences -> Profiles -> Basic -> Shell:
22nd Apr 2020, 1:51 am
TIL Get Skitch working on Catalina — I really like Skitch for taking screeshots, mainly because I like to snap a quick shot and then drag the icon onto a Google Doc or similar without saving the file anywhere.
22nd Apr 2020, 1:48 am
TIL Use labels on Cloud Run services for a billing breakdown — Thanks to [@glasnt](https://github.com/glasnt) for the tip on this one. If you want a per-service breakdown of pricing on your Google Cloud Run services within a project (each service is a different deployed application) the easiest way to do it is to apply labels to those services, then request a by-label pricing breakdown.
22nd Apr 2020, 12:52 am
TIL Running pip install -e .[test] in zsh on macOS Catalina — macOS Catalina uses `zsh` rather than `bash` as the default shell (apparently because Apple don't like GPL 3).
21st Apr 2020, 7:55 pm
TIL macOS Catalina sort-of includes Python 3 — Once you have installed the "command line tools" for Catalina using the following terminal command:
21st Apr 2020, 6:19 pm
TIL Null case comparisons in SQLite — I wanted to say "output this transformed value if it's not null, otherwise nothing". The recipe I figured out was:
21st Apr 2020, 4:43 pm
TIL Using macOS stickies to display a workshop link on the screen — When giving a workshop it's often useful to have a URL to the workshop materials visible on screen at all times. I use a bit.ly link for these.
20th Apr 2020, 4:41 pm
TIL Running different steps on a schedule — Say you have a workflow that runs hourly, but once a day you want the workflow to run slightly differently - without duplicating the entire workflow.
20th Apr 2020, 2:39 pm
TIL Lag window function in SQLite — Here's [how to use a lag window…
19th Apr 2020, 11:23 pm
TIL Running a Python ASGI app on Vercel — Vercel really wants you to deploy static assets with [serverless functions](https://vercel.com/docs/serverless-functions/introduction) tucked away in a separate folder. They suggest creating modules like `api/index.py` which will be served up automatically as API backends to your client-side JavaScript.
19th Apr 2020, 10:28 pm

Years