You can specify the SQLite database and pass options (pragmas like cache_size, journal_mode, ...) on the command line when you start the Ktistec server. The following example sets the cache size to 20,000 pages (up from the default of 2,000 pages) which improves performance on larger instances.

KTISTEC_DB=~/ktistec.db\?cache_size=-20000 ./server

You can also enable the write-ahead log (but make sure you know what that means).

KTISTEC_DB=~/ktistec.db\?journal_mode=wal\&synchronous=normal ./server

Pragmas supported are limited to those listed here.

#ktistec #fediverse #activitypub #crystallang

A new release of ktistec that improves database performance is imminent. In the past, database optimization usually meant "fixing a bunch of poorly constructed queries", and I'm sure there's more of that to do—I'm not an expert. But this time, I found most of the queries were as good as they were going to get on my watch (I'm not an expert). If you have a million records and you need to filter and count them, that's just going to take some time...

So this time, I focused on caching the results of queries like that (which really means I focused on cache invalidation, right). A case in point is commit d544b1af. Previously, the nodeinfo endpoint filtered and counted posts on every request, and it took +80msec to do that. Worse, the filtering pushed everything else out of the sqlite page cache, which made the next, unrelated database query slow!

Caching this value, and only recounting when I post something, not only dropped the service time for the request to ~1msec but actually improved database performance, generally!

More to come...

#ktistec #fediverse #activitypub #crystallang

If you're running an instance of Ktistec and want to see what other ActivityPub instances are sending you, turn on JSON-LD processing debug logging.

1. Go the the /system URL.
2. Find the ktistec.json_ld setting.
3. Select "Debug" and save.

Ktistec will dump received activities to the log, after the activity has been parsed into JSON but before JSON-LD expansion.

2025-01-22 14:53:17 UTC 409 POST /actors/toddsundsted/inbox 4.29ms
2025-01-22T14:53:17.597172Z  DEBUG - ktistec.json_ld: {"@context" => ["https://www.w3.org/ns/activitystreams", "https://w3id.org/security/v1"],
"id" => "https://random.site/users/FooBar#delete", "type" => "Delete", "actor" => "https://random.site/users/FooBar", "object" => "https://random.site/users/FooBar", "to" => ["https://www.w3.org/ns/activitystreams#Public"], 
"signature" => {"type" => "RsaSignature2017", "creator" => "https://random.site/users/FooBar#main-key", "created" => "2025-01-22T14:52:40Z", "signatureValue" => "01234567890abcdefghijklmnopqrstuvwxyz=="}}

Answer to a FAQ:
The server returns HTTP status code 409 ("Conflict") if it has already received an activity.

#ktistec #fediverse #activitypub

Ktistec release v2.4.5 rolls out the build time and executable size optimizations I've been blogging about here. It also fixes a few small bugs.

Fixed

• Handle @-mentions with hosts in new posts.
• Handle HEAD requests for pages with pretty URLs.
• Destroy session after running scripts.

Changed

• Delete old authenticated sessions.

I've started a branch full of query optimizations. My general rule—as highlighted in the server logs—is if a query takes longer than 50msec, it takes too long. It's time to address some problems...

#ktistec #fediverse #activitypub #crystallang

Ktistec release v2.4.4 fixes a few things in the prior release and introduces at least one killer feature!

Fixed

• Always get the attachments. (fixes #119)
• Don't run scripts until the server has been configured.

Changed

• ⭐️ Make the editor toolbar sticky.
• Clear the cached translator when the settings change.

I'm spending some cycles looking at the size of the server executable. You can read about my approach to reducing Crystal Language executable size and build time here.

#ktistec #fediverse #activitypub #crystallang

Release v2.4.2 fixes a few more bugs. Only one is a regression—I found the others while testing. In this release:

Fixed

• Fix metrics chart line labels.
• Permit del, ins, and s elements in sanitized HTML.
• Only store the redirect_after_auth_path on browser navigation.
• Add "content" property to editor JSON error response.
• Use FileUtils.mv to move uploaded files. (fixes #117)

Thanks to @jayvii for help with troubleshooting the last one!

#ktistec #fediverse #activitypub #crystallang

Eh, I didn't test enough and released v2.4.0 of Ktistec with a few annoying regressions. Release v2.4.1 fixes them! ☹️ 😠 😡 🤬

Fixed

• Handle edge cases and race conditions in script runner.
• Reconnect editor autocomplete support.
• Fix permissions on uploaded files.

#ktistec #fediverse #activitypub #crystallang

I've been thinking about the demise of botsin.space. Running a site for bots is hard (and expensive) but writing and running an ActivityPub-based bot should be easy.

To prove this was the case I added experimental support for bots/automations to Ktistec in the form of scripts that the server periodically runs. These scripts can be in a programming language of your choice. The server provides credentials for its API in the process environment (if you can use curl you can publish posts), simple interaction happens via stdin/stdout/stderr, and the complexity of using ActivityPub is abstracted away.

The code is only available on the following branch for the moment:

    https://github.com/toddsundsted/ktistec/commits/run-scripts/

There are a couple example shell scripts here:

    https://github.com/toddsundsted/ktistec/commit/4982925a...

I have a few enhancements in mind, but it's already proven useful as a means to periodically log data from my server host, and I'll use it, when finished, to publish release notes.

#ktistec #activitypub #fediverse #bots