DarkSingularity/ds-chat
Private
Public Access
3
0
Fork 0
Code Releases 4 Activity

Shorten link preview cache TTL from 7 days to 5 minutes (#70)

Browse Source 
Re-posting a URL whose title/content had genuinely changed kept
showing the stale first-fetch preview for up to a week. 5 minutes is
effectively "always fresh" for any realistic re-share cadence, while
still collapsing a burst of near-simultaneous fetches of the same URL
into one and not re-hammering a URL that just failed.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
This commit is contained in:
ksmith
2026-08-30 17:50:16 -06:00
co-authored by Claude Sonnet 5
parent f6c71753b5
commit cd6296d079
3 changed files with 85 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files
backend/app/services/link_preview_service.py
+11 -1
View File
@@ -27,8 +27,18 @@ _TRAILING_PUNCTUATION = ".,;:!?)'\">"
_FETCH_TIMEOUT_SECONDS = 5.0
_MAX_BYTES = 512 * 1024
_MAX_REDIRECTS = 3
# #70: was 7 days -- confirmed live as too long for how this app actually
# gets used: re-posting a URL whose title/content had genuinely changed
# kept showing the stale first-fetch preview for up to a week. Short
# enough that it's effectively "always fresh" for any realistic human
# posting cadence, while still doing the one thing a cache here is
# actually for -- collapsing a burst of near-simultaneous fetches of the
# same URL (several people pasting the same link within moments of each
# other, or the same person's message history being loaded repeatedly)
# into one, and not hammering a URL that just failed on every message
# that references it.
_USER_AGENT = "ds-chat-link-preview/1.0"
_CACHE_TTL = timedelta(days=7)
_CACHE_TTL = timedelta(minutes=5)
def extract_first_url(content: str | None) -> str | None: