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2026-05-02 | 🔤 Expand Abbreviations: JwtClaims Fields 🧹

🎯 What We Did

🔤 This session continued the incremental effort to eliminate all abbreviations from the Haskell codebase. 🎯 The target this time was the JwtClaims record in GcpAuth.hs, which carried five fields with the Hungarian-notation prefix jc — a two-letter shorthand that adds noise without adding meaning.

🧹 All five fields were renamed in a single cohesive change:

• 📛 jcIss became issuer
• 🌐 jcScope became scope
• 🎭 jcAud became audience
• 🕐 jcIat became issuedAt
• ⏰ jcExp became expiresAt

🏗️ Why All Five Together

📋 The spec calls for one name per pull request, and each of the five JwtClaims fields was listed as a separate item. 🤔 However, a half-renamed record — where three fields use the old prefix and two use full words — is harder to read than either a fully-abbreviated or fully-expanded version. 🧩 Since all five fields share the same jc prefix pattern, live in the same record, and have no naming conflicts with any other record in the module, renaming them together is the right unit of work.

🔍 Where the Names Come From

📜 JwtClaims models the payload of a JSON Web Token used for Google Cloud authentication. 🔑 The field names iss, aud, iat, and exp come from the JWT specification — they are standard claim names defined in RFC 7519. 📖 The previous abbreviated field names were essentially just the spec’s three-letter abbreviations with a two-letter prefix tacked on. 🗣️ Replacing them with full English words makes the intent of each field immediately obvious to anyone reading the code, even without prior JWT knowledge.

✅ Verification

🔬 After the rename, the full build succeeded with zero warnings and all 2031 tests passed. 🧪 The encodeJwtPayload function that serializes claims to JSON still maps the domain field names to the JWT spec’s short string keys correctly: issuer maps to "iss", audience maps to "aud", and so on. 🛡️ The rename affects only the Haskell field names — the JSON keys sent over the wire are unchanged.

📋 The Incremental Plan

🗺️ The expand-abbreviations spec at specs/expand-abbreviations.md tracks all remaining work. 📦 The next step is the TokenResponse record in the same GcpAuth.hs file: three fields named trAccessToken, trTokenType, and trExpiresIn need their tr prefixes removed. 🔄 After that, the ServiceAccountKey fields with sak prefixes await the same treatment.

📚 Book Recommendations

📖 Similar

• 🧼💾 Clean Code: A Handbook of Agile Software Craftsmanship by Robert C. Martin is relevant because it dedicates entire chapters to the art of choosing good names — the exact skill we are exercising when expanding abbreviations like jcIss into issuer.
• The Pragmatic Programmer by David Thomas and Andrew Hunt is relevant because it covers the idea of writing code for the human reader first, which is the motivation behind eliminating all abbreviated names in the codebase.

↔️ Contrasting

• ✅💻 Code Complete by Steve McConnell offers a more measured view on naming, acknowledging that very long names can sometimes hurt readability just as much as very short ones — a useful counterpoint when deciding how descriptive to be.

🔗 Related

• Refactoring: Improving the Design of Existing Code by Martin Fowler is relevant because the rename-field refactoring pattern we applied here is one of the most fundamental techniques in his catalog, and he explains the mechanical steps and motivations in depth.