I've been archiving my Reddit data slowly over the past couple weeks while the API is still freely accessible. It has been very time-consuming because of how awful getting correct/complete data is. You'll probably run into some of these problems if you're attempting your own archive as well.

TL;DR

• The GDPR export is extremely slow. It has most data you would want though.
• The API export is limited to 1,000 items. It also has most data you would want and more. If a subreddit is privated while you query the API for an API export, it will not return in your subreddits and you will not see any comments or posts from it. The data will silently be missing.
• Reddit chat archiving via the API is currently flaky.
• Reddit thread archiving was pretty simple. The archive.org archive also has most every post archived you would want. 29 of 30 I tested from my dataset were found.

GDPR Export

From what I gather, Reddit's GDPR export includes the following1:

• Saved posts and comments (id and permalink)
• Votes for posts and comments (id, permalink, and direction)
• Your own comments and posts (id, permalink, date, ip, subreddit, body, etc...)
• Message and chat history
• IP log
• quite a bit of other smaller pieces of data

The GDPR export is also extremely slow. I can't fully confirm the above because I'm still waiting for mine >:( . It's been >7 days2.

API Export

I used rexport by karlicoss in the past when experimenting with promnesia so I ran that against all of my Reddit accounts to download their data. The API limits queries to the last 1,000 of each item type (posts, comments, etc) but this was not a problem for my accounts.

I only realized later that I was still missing some data. Apparently privated subreddits are silently omitted from a lot of the API returns, exacerbated by the subreddit blackout3. Running the API export now (6/29/2023) I get a lot more data.

Chat Export

Most of my Reddit chats were in the old chat system (SendBird). This seems hard to export or even find in the UI anymore4, especially with Reddit actively messing with the infrastructure around it at the current moment. I found reddit-chat-archiver but wasn't able to get it to return anything, even with tweaks. Some of the endpoints are currently returning 404s.

For the new Matrix-based chat, I found Rexit but didn't have the dependencies to run and test it. Supposedly chat was to be migrated to the new platform so in the future Rexit should work. I have only had one of my chats migrated though so who knows...

Thread Archiving

Neither the GDPR or API export will give you the entire thread of a post, including all comments. I used a modified version of RedditArchiver-standalone by Ailothaen for this. By default you get a minimal but functional .html file of the archived thread. I also added my own quick .json export for future use.

I'm no good with CLI, but I hacked together a jq and xargs invocation to archive all my upvoted, submitted, saved, and commented posts from the rexport output.

jq '[.submissions[], .saved[], .upvoted[], .comments[] | if .link_id then .link_id[3:] else .id end] | unique | .[]' ~/archive/reddit/export-user-2023-06-11.json | xargs -i python ~/RedditArchiver.py -c ./config-user.yml -i {} -o ~/archive/reddit/

archive.org

Some of the threads I wanted to archive are still privated. I heard ArchiveTeam has been rapidly collecting web crawl snapshots onto archive.org and wanted to check out how that was doing.

I took all the links from my API export and used jq to form a lookup URL onto archive.org. Apparently it was important to use old.reddit.com instead of www.reddit.com when looking up the archived URLs on archive.org otherwise you won't see much5.

jq '[.submissions[], .saved[], .upvoted[], .comments[] | "https://web.archive.org/web/2/http://old.reddit.com" + .permalink] | unique | .[]' ~/archive/reddit/export-user-2023-06-11.json

I tried 30 different threads, including some from pretty obscure subreddits, and I amazed that only 1 thread was missing.

addendum

I'm happy I have most of my data off of the platform, now it's just an impatient wait for my GDPR export. I'm still not quite sure how my usage of Reddit will change yet, though I know I won't be using BaconReader6 anymore. My use will most likely be restricted to just the web view as a tool in search engines for human-discussion-esque content. Still hoping my development plans pan out and I have a better data storage/retrieval system to workaround all of this mess.