grschafer (u/grschafer)

grschafer commented on Hands-On with PostgreSQL Authorization – Part 2 – Row-Level Security tangramvision.com/blog/ha... · Posted by u/grschafer

brownkonas · 4 years ago

Good article on what's possible and how to do it, but is row level security scalable in any way for a production application? Not so much on the performance impact of any one query but maintaining the definition of what a role can or can't do (if a db user = an application role). It also seems like it would complicate managing db connections as well, separate pools for each db user? If you have 10 roles, you have to open up at least 10 connections to avoid connection opening latency.

Leveraging most RDBMS security features seem to be geared for an ever shrinking set of use cases where a mostly static set of users are given direct access to a SQL prompt, or a simple record to GUI application interface.

grschafer · 4 years ago

Good questions! Regarding maintaining the definition of what a role can or can't do -- I think this comes down to how you organize your SQL. If you keep authz declarations in one place, it's going to be more maintainable than if they're spread across many database migrations. One way you can keep those authz declarations in one place is by doing development/maintenance on that one place then using a database-diffing tool[1] to generate migrations based on whatever changes you made.

Regarding database connections -- one way to avoid needing a connection per user is to use something like PostgREST[2] to handle incoming requests, identify the user making the request, and use an existing db pool connection to switch roles and execute whatever queries are requested. EDIT: RedShift1 beat me to this explanation by a little bit! :)

RLS certainly isn't the answer for every domain or problem size, but I've been surprised by how powerful it is compared with how relatively unknown it is.

[1]: https://supabase.com/blog/2021/03/31/supabase-cli#migrations

[2]: https://postgrest.org/en/stable/auth.html

grschafer commented on Show HN: Depth Sensor Visualizer tangramvision.com/resourc... · Posted by u/grschafer

grschafer · 5 years ago

Hello HN! I made this tool to hopefully help computer vision and robotics folks play around with camera parameters and compare different commercial depth cameras. This tool was inspired by another, similar tool: https://www.smeenk.com/webgl/kinectfovexplorer.html

Also shoutout to three.js for having an incredible variety of examples and great documentation to learn from. And credit to mixamo for the android-esque robot model.

Feedback and suggestions welcome! :)

grschafer · 5 years ago

Open-sourced the code here: https://gitlab.com/tangram-vision-oss/fov-visualizer

grschafer commented on Show HN: Depth Sensor Visualizer tangramvision.com/resourc... · Posted by u/grschafer

grschafer · 5 years ago

Hello HN! I made this tool to hopefully help computer vision and robotics folks play around with camera parameters and compare different commercial depth cameras. This tool was inspired by another, similar tool: https://www.smeenk.com/webgl/kinectfovexplorer.html

Also shoutout to three.js for having an incredible variety of examples and great documentation to learn from. And credit to mixamo for the android-esque robot model.

Feedback and suggestions welcome! :)