Test-drive a CAR
When apps sync data from your PDS, it comes in a format called a Content Addressable aRchive: a CAR file! 🚗
This archive can contain your entire "repo" (repository), which is your records, their keys (the record's collection and rkey combined). It also has some additional structural info for the MST, but we're not going to worry about that just yet!
YOU WOULDN'T DOWNLOAD A CAR
…who are we kidding,
Your challenge: find the verificationCode hidden inside.
Hint: atproto CAR tools (easy-mode)
There are some nice web tools for poking around in a CAR:
- Satnav from Blacksy
- Archive explore on boat.kelinci.net
- Explore archive at PDSls
Or, if you have the goat command-line utility installed, try running:
goat repo --help
CAR libraries (write some code)
If you're feeling adventurous, you can write a program to show the contents of a CAR file. Some libraries that can help:
-
python:
atproto_core.car(has sample code) -
javascript:
@atcute/repo(advanced) -
golang:
indigo/atproto/repo(advanced) -
rust:
jacquard_repo(advanced)
Binary spelunking (bits & bytes)
Oh, you want hard-mode? Here:
Binary hint cheat
Text inside records is not compressed or weirdly encoded, and CAR just length-prefixes blocks without changing any bytes, so strings or even hexdump -C on your CAR might be worth trying…