Summary

Implements redirect rules (#529) - a highly requested feature that allows pattern-based URL matching for short links.

What it does

Instead of creating individual short links for every URL, users can now create a single redirect rule like:

• /blog/* → redirects any /blog/hello-world, /blog/2024/post, etc.
• /docs/:slug → redirects /docs/intro, /docs/api with captured params

Changes

Schema:

• Added isRule (boolean) and rulePattern (string) fields to Link model
• Added index on [domain, isRule] for efficient rule lookup

Middleware:

• After exact link match fails, falls back to pattern matching
• Rules cached per domain in Redis + LRU cache
• Most specific pattern matches first (specificity scoring)

Analytics:

• Uses existing alias_link_id field in Tinybird to track matched paths
• Clicks aggregate under rule link, but you can see individual paths hit

API:

• Rules are just links with isRule: true
• Existing link endpoints work (POST /api/links with isRule + rulePattern)
• Pro plan required for redirect rules

Pattern syntax

/blog/*           → matches /blog/anything, /blog/foo/bar
/docs/:slug       → matches /docs/intro, captures { slug: "intro" }
/api/:v/:endpoint → matches /api/v1/users, captures { v: "v1", endpoint: "users" }

Testing needed

• Pattern matching edge cases
• Cache invalidation when rules updated
• Performance under load
• UI for creating rules (not included - backend only)

Closes #529

Happy to adjust anything based on feedback!