fix: parse Link rel="alternate" in any parameter position#77
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fix: parse Link rel="alternate" in any parameter position#77
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The _parse_link_alternates regex required rel="alternate" to appear immediately after the first semicolon following the URI-Reference. This meant Link headers with other parameters before rel (e.g., title, type) would silently fail to match, violating RFC 8288 section 3 which allows parameters in any order. Split the match into two steps: check for rel="alternate" anywhere in the link value, then extract the URI. Also makes the match case-insensitive per RFC 8288 section 2.1.1. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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What: Fix
_parse_link_alternatesto matchrel="alternate"regardless of its position among Link header parameters.Why: The regex required
rel="alternate"immediately after the first;, so a header like<url>; title="cross-signed"; rel="alternate"silently failed to match. RFC 8288 section 3 allows parameters in any order. While current Let's Encrypt responses putrelfirst, other CAs may not — and the spec doesn't require it.How: Split into two regex steps: first check
;\s*rel="alternate"anywhere in the value (case-insensitive per RFC 8288 §2.1.1), then extract the URI from<...>. This is a superset of #72 (which only adds case-insensitivity).Testing: 13 test cases covering: no header, single/multiple alternates, non-alternate filtering, case variations, whitespace, and — the new cases —
relappearing after other params liketitleortype.🤖 Generated with Claude Code