Version 0.4.3 of Braindump, I Need More Functional Tests.
Yesterday, I shipped a new release of braindump. It was awesome. Until I tried to use it this morning and realized that notes were no longer being saved when you edit them. So today I cut a new release that fixes that bug, as well as implementing a new feature where you can see what notes you have shared in the past. This also addresses an issue with sharing notes, so you should be able to send notes via email again. Normally, when a product is being released on a regular cadence it is exciting. In this case, it just means that I really need more functional tests.
Post Mortem of Note Saving Bug
For those who are curious, I will document what happened in the hopes that it does not affect others in the future. Braindump was originally written using WTForms, which has CSRF protection built in so you don't have to think about it. Recently, I have begun transitioning away from WTForms in lieu of regular forms that are submitted via AJAX. The most visible benefit is that you can see and edit all of your notes from the main page, instead of having to click into each note in order to edit it. After switching to AJAX, I quickly realized that I was no longer sending a CSRF token with POST and PUT requests, which is probably a bad thing. I enabled it in the previous release. Even though I got this to work in the login and registration modal (which are true forms), I didn't consider the PUT request when editing a note. This is not a form at all, but a method that fires whenever you stop typing. Naturally, since there was no token and the endpoint was not marked as exempt, the response was a 400 error (missing CSRF token). My solution was to add the token as a meta tag to every page, and then send it along in the request headers of the AJAX call.Enable CSRF
// app/__init__.pycsrf = CsrfProtect()
def create_app(config_name): … csrf.init_app(app) …
return app
Token in the Header
// app/templates/app/app_base.html // This works because csrf_token() is in the global scope.<meta name=“csrf-token” content=" csrf_token() " />
AJAX Method to add the token before sending the PUT request.
// frontend/js/src/braindump.editor.jssaveNote: function(id, content) {
var csrftoken = $('meta[name=csrf-token]').attr('content') $.ajax({ beforeSend: function(xhr) { xhr.setRequestHeader("X-CSRFToken", csrftoken) }, url: `/edit/<span class="cp">${</span><span class="nb">id</span><span class="cp">}</span>`, data: JSON.stringify({ 'body': content, }), contentType: 'application/json', type: 'PUT', success: function (response) { console.log(response); }, error: function (error) { console.error(error); } });
},
Thank you for reading! Share your thoughts with me on bluesky, mastodon, or via email.
Check out some more stuff to read down below.
Most popular posts this month
- 2024
- Reinstalling Windows at 1am
- SQLite DB Migrations with PRAGMA user_version
- My Custom Miniflux CSS Theme
- How to Disable Wayland in Debian Testing
Recent Favorite Blog Posts
This is a collection of the last 8 posts that I bookmarked.
- The AGI economy is coming faster than you think from Freethink
- Rolling the ladder up behind us from Xe Iaso's blog
- In Praise of “Normal” Engineers from charity.wtf
- Reports of Bluesky's death have been greatly exaggerated from The Torment Nexus
- What Would a Kubernetes 2.0 Look Like from matduggan.com
- We Can Just Measure Things from Armin Ronacher's Thoughts and Writings
- The Gentle Singularity from Sam Altman
- Whale Watching from https://popagandhi.com/
Articles from blogs I follow around the net
How Many Mildliner Colours Are There Now?
I made a mildliner reference site to keep track of all the colours
via Robb Knight • Posts • Atom Feed June 27, 2025Resupply stablecoin lender exploited for $9.3 million
An attacker was able to exploit a vulnerability in a smart contract used by the Resupply stablecoin lender to extract about $9.3 million from the project. After depositing around $200,000, they were able to inflate the price of anoth…
via Web3 is Going Just Great June 27, 2025Self-driving is finally happening
I still remember how the car industry got all excited back in 2017 about how steering wheels would soon be obsolete. Every concept car then was a living room on wheels, seats facing inwards. The self-driving revolution was imminent, they said. Well, it …
via David Heinemeier Hansson June 27, 2025Generated by openring