fix: backdate JWT iat to avoid clock-skew 401s#64
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The server auth token stamped `iat = Time.now.to_i`. Because `iat` is a whole-second value (RFC 7519 NumericDate) and the server applies minimal forward leeway, a small fraction of requests were rejected with "token used before issue at (iat)" (HTTP 401) whenever the caller's clock was marginally ahead of the server and the second-truncation landed on a boundary. Observed at ~0.03% of requests, spread uniformly across all caller hosts. Backdate `iat` by Client::AUTH_IAT_LEEWAY_SECONDS (5s) so the token is always safely behind the server clock. The legacy stream-chat-ruby client never sent `iat`, which is why upgrades from it newly exposed this. Co-authored-by: Cursor <cursoragent@cursor.com>
Fixes Lint/UselessConstantScoping: `private` does not affect constants, so the constant is declared at the top of the class instead. Co-authored-by: Cursor <cursoragent@cursor.com>
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Summary
Backdate the JWT
iatclaim on server auth tokens by a few seconds so tokens are never stamped ahead of the server clock.iatis a whole-second value (RFC 7519 NumericDate), soTime.now.to_itruncates to the second. With no safety margin, a caller whose clock is marginally ahead of the server can intermittently gettoken used before issue at (iat)(HTTP 401) when the truncation lands on a second boundary. BackdatingiatbyClient::AUTH_IAT_LEEWAY_SECONDS(5s) keeps it safely in the past.Changes
Client#generate_auth_header: stampiat: Time.now.to_i - AUTH_IAT_LEEWAY_SECONDS.spec/auth_token_spec.rbassertingiatis backdated and never ahead of "now".[Unreleased] / Fixed.Test plan
bundle exec rspec spec/auth_token_spec.rb