TUL/Exclude /browse, /search and admin paths from SSR (port of upstream #4332) - #1453
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TUL/Exclude /browse, /search and admin paths from SSR (port of upstream #4332)#1453milanmajchrak wants to merge 1 commit into
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DSpace#4332) Crawlers were feeding on SSR-rendered /browse pages: DSpace reflects unknown query params into generated links, and non-decoding crawlers turn the escaped separator into ever-growing amp;value params - an infinite URL space. On 7.5 every such URL is a full SSR render (~21 backend calls), which took the site down on Aug 6-9. Ports upstream dspace-7_x PR DSpace#4332 (excludePathPatterns) natively: excluded paths are served as CSR shell with no links to follow. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Problem description
Reported issues
New Relic: PING TUL DSPACE FE/BE alerts Aug 6-9 (504s, read timeouts). Backend at 130 % CPU, 289k upstream timeouts/day, successful responses dropped from 94k to 34k/day.
Not-reported issues
DSpace reflects unknown query params into links it generates on /browse and /search. A crawler that does not decode HTML entities turns the escaped
&into anamp;valueparam, gets a valid 200 page with 21 new links, and loops - an infinite URL space. 52 % of all requests during the incident were these URLs.Reproducible on any 7.5 instance:
curl -s 'https://dspace.tul.cz/browse/author?zzz=1' | grep -c 'zzz=1'(non-zero = param reflected into links).Analysis
Upstream closed this class of traffic in 7.6.5 by excluding /browse, /search and admin paths from SSR (DSpace#4332): excluded paths get the CSR shell, so a non-JS crawler sees no links to follow and each hit costs no backend calls. customer/TUL is on 7.5 where
excludePathPatternsdoes not exist, so this PR ports DSpace#4332 natively.universalis not yaml-configurable in 7.5 - the defaults in the environment files are the effective values.Interim mitigation (nginx 410 on
amp;URLs) is already deployed on the machine and can stay.Verified: exclusion regexes tested against real paths (/browse/author, /search -> CSR; /items/, /handle/, / -> SSR). Not verified: full yarn build on this branch - needs CI.
After deploy:
curl -s https://dspace.tul.cz/browse/author | wc -cshould drop from ~455 kB to ~2 kB.Problems
Trade-off: browse pages leave SSR also for legitimate non-JS crawlers (Googlebot). Same default upstream ships since 7.6.5 and what vsb/mendelu/lindat already run.