Part of duplicate code analysis: #1882

Summary

The [TIMESTAMP] [LEVEL] [CATEGORY] MESSAGE log-line formatting block is copy-pasted verbatim in at least 3 logger files. A single-character format change (e.g., switching from RFC3339 to RFC3339Nano) requires editing multiple files.

Duplication Details

Pattern: Inline Log-Line Timestamp Construction

• Severity: Medium
• Occurrences: 5 instances across 3+ logger files
• Locations:
  • internal/logger/file_logger.go (lines ~85–89)
  • internal/logger/server_file_logger.go (lines ~111–115)
  • internal/logger/markdown_logger.go (similar block)

Exact duplicate (file_logger.go and server_file_logger.go are byte-for-byte identical for these 4 lines):

timestamp := time.Now().UTC().Format(time.RFC3339)
message := fmt.Sprintf(format, args...)
logLine := fmt.Sprintf("[%s] [%s] [%s] %s", timestamp, level, category, message)
fl.logger.Println(logLine)  // server_file_logger: logger.Println(logLine)

Impact Analysis

• Maintainability: Format changes (timestamp precision, bracket style, JSON output) require multi-file edits
• Bug Risk: Low for now, but any drift (e.g., one file switching to UTC+local or adding a request-ID field) will silently produce inconsistent log formats
• Code Bloat: ~20–30 lines of duplicated formatting logic (small but exact)

Refactoring Recommendations

1. Extract FormatLogLine utility (quick win, ~30 min effort):

   // internal/logger/format.go
   func FormatLogLine(level, category, format string, args ...any) string {
       timestamp := time.Now().UTC().Format(time.RFC3339)
       message := fmt.Sprintf(format, args...)
       return fmt.Sprintf("[%s] [%s] [%s] %s", timestamp, level, category, message)
   }

   Each logger's write path becomes:

   fl.logger.Println(FormatLogLine(level, category, format, args...))

2. Consider timeutil package — internal/timeutil/ already exists; FormatLogLine or at minimum FormatTimestamp() could live there to avoid circular imports.

3. Single source of truth for log format — store the format string as a package-level constant so it can be changed in one place.

Implementation Checklist

• Create internal/logger/format.go with FormatLogLine helper
• Replace inline blocks in file_logger.go, server_file_logger.go, markdown_logger.go
• Run make test to verify no output format regressions
• Check if any tests assert on exact log-line format and update them

Parent Issue

See parent analysis report: #1882
Related to #1882

Generated by Duplicate Code Detector · ◷

• expires on Mar 21, 2026, 2:57 AM UTC