Class: RailsErrorDashboard::Services::LocalizedTimeFormatter

Inherits:
Object
  • Object
show all
Defined in:
lib/rails_error_dashboard/services/localized_time_formatter.rb

Overview

strftime with the word-producing directives resolved from RED's own dictionary.

WHY THIS EXISTS

Ruby's strftime is not locale-aware: %B is "August" whatever RED's locale is. On the dashboard that does not matter, because a timestamp is rendered as a and the browser re-renders it through formatDateTime() using the red.js.* month/day/meridian vocabulary P3-T2 added. Anywhere there is no browser — email (P4-T2), Slack and Discord payloads (P4-T3) — the server has to do that substitution itself.

Sharing one implementation is the point: an email, a Slack message and the dashboard should not disagree about what a date looks like.

Takes the locale as an argument rather than reading Current, because every caller runs inside a job where Current is nil or belongs to an unrelated request.

Constant Summary collapse

LOCALIZED_DIRECTIVES =

The directives whose output is a word, and therefore locale-dependent: %B %b (month), %A %a (weekday), %p %P (meridian). Everything else (%Y, %m, %d, %H, %M, %S, %Z …) is digits or a timezone abbreviation and is left to strftime.

/%[BbAaPp]/
PLACEHOLDER =

Stand-in for a localized word while strftime runs. Contains no percent, so strftime cannot read it as a directive, and no space, so it cannot alter the spacing the pattern asked for. The index keeps two occurrences of the same directive independent.

"\u0000RED%<index>d\u0000"

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(locale) ⇒ LocalizedTimeFormatter

Returns a new instance of LocalizedTimeFormatter.



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# File 'lib/rails_error_dashboard/services/localized_time_formatter.rb', line 44

def initialize(locale)
  @locale = locale
end

Class Method Details

.call(time, pattern:, locale:) ⇒ String

Parameters:

  • time (Time)
  • pattern (String) —

    a strftime pattern

  • locale (String)

Returns:

  • (String) 


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# File 'lib/rails_error_dashboard/services/localized_time_formatter.rb', line 40

def self.call(time, pattern:, locale:)
  new(locale).render(time, pattern)
end

Instance Method Details

#render(time, pattern) ⇒ Object

Two-pass, via placeholders: substituting a translated month name directly would put arbitrary text into the pattern, and while a French "%A" -> "mardi" is harmless, a translation containing a literal percent sign would corrupt every directive after it. The placeholder carries no percent, so strftime cannot misread it.



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# File 'lib/rails_error_dashboard/services/localized_time_formatter.rb', line 53

def render(time, pattern)
  replacements = []

  staged = pattern.gsub(LOCALIZED_DIRECTIVES) do |directive|
    word = localized_word(directive, time)
    next directive if word.nil?

    replacements << word
    format(PLACEHOLDER, index: replacements.length - 1)
  end

  rendered = time.strftime(staged)

  replacements.each_with_index do |word, index|
    rendered = rendered.sub(format(PLACEHOLDER, index: index), word)
  end

  rendered
end