Stop caching the local tzone

CHANGELOG.md

@@ -4,6 +4,8 @@
 
 ## et-orbi 1.1.1  not yet released
 
+- Stop caching the local tzone, cache the tools used for determining it
+
 
 ## et-orbi 1.1.0  released 2018-03-25
 

bak/bench.rb

@@ -0,0 +1,75 @@
+
+require 'benchmark'
+
+require 'tzinfo'
+require 'et-orbi'
+
+n = 10_000
+
+p ENV['TZ']
+p EtOrbi.determine_local_tzone
+p EtOrbi.send(:determine_local_tzones)
+
+A = [
+  'ENV["TZ"]',
+  proc do
+    ENV['TZ']
+  end ]
+
+B = [
+  'EtOrbi.os_tz',
+  proc do
+    EtOrbi.os_tz
+  end ]
+
+C = [
+  'TZInfo::Timezone.get("xxx")',
+  proc do
+    ::TZInfo::Timezone.get('America/Los_Angeles')
+  end ]
+
+D = [
+  'EtOrbi.determine_local_tzone',
+  proc do
+    EtOrbi.determine_local_tzone
+  end ]
+
+E = [
+  'TZInfo::Timezone.all',
+  proc do
+    #::TZInfo::Timezone.all
+  end ]
+
+puts
+puts "Ruby #{RUBY_VERSION}p#{RUBY_PATCHLEVEL} (#{RUBY_RELEASE_DATE}) [#{RUBY_PLATFORM}]"
+puts `uname -a`
+puts
+puts "the smaller the better"
+puts
+
+2.times do
+
+  Benchmark.bmbm do |bm|
+    bm.report(A[0]) { n.times(&A[1]) }
+    bm.report(B[0]) { n.times(&B[1]) }
+    bm.report(C[0]) { n.times(&C[1]) }
+    bm.report(D[0]) { n.times(&D[1]) }
+    bm.report(E[0]) { n.times(&E[1]) }
+  end
+
+  puts
+end
+
+## Iterations Per Second Testing
+## gem install benchmark-ips
+#require 'benchmark/ips'
+#
+#Benchmark.ips do |ips|
+#  ips.report('Version A') do
+#    # Code to benchmark
+#  end
+#
+#  ips.report('Version B') do
+#    # Code to benchmark
+#  end
+#end

lib/et-orbi.rb

@@ -47,7 +47,7 @@ def parse(str, opts={})
         opts[:zone] ||
         str_zone ||
         find_olson_zone(str) ||
-        local_tzone
+        determine_local_tzone
 #p [ :parse, :zone, zone ]
 
       str = str.sub(zone.name, '') unless zone.name.match(/\A[-+]/)
@@ -143,7 +143,7 @@ def get_tzone(o)
 
       return o if o.is_a?(::TZInfo::Timezone)
       return nil if o == nil
-      return local_tzone if o == :local
+      return determine_local_tzone if o == :local
       return ::TZInfo::Timezone.get('Zulu') if o == 'Z'
       return o.tzinfo if o.respond_to?(:tzinfo)
 
@@ -156,35 +156,17 @@ def get_tzone(o)
       (::TZInfo::Timezone.get(o) rescue nil)
     end
 
-    def local_tzone
-
-      @local_tzone_tz ||= nil
-      @local_tzone_loaded_at ||= nil
-
-      @local_tzone = nil \
-        if @local_tzone_loaded_at && (Time.now > @local_tzone_loaded_at + 1800)
-      @local_tzone = nil \
-        if @local_tzone_tz != ENV['TZ']
-
-      @local_tzone ||=
-        begin
-          @local_tzone_tz = ENV['TZ']
-          @local_tzone_loaded_at = Time.now
-          determine_local_tzone
-        end
-    end
-
     def render_nozone_time(seconds)
 
       t =
         Time.utc(0) + seconds
       ts =
         t.strftime('%Y-%m-%d %H:%M:%S') +
         ".#{(seconds % 1).to_s.split('.').last}"
+      tz =
+        EtOrbi.determine_local_tzone
       z =
-        EtOrbi.local_tzone ?
-        EtOrbi.local_tzone.period_for_local(t).abbreviation.to_s :
-        nil
+        tz ? tz.period_for_local(t).abbreviation.to_s : nil
 
       "(secs:#{seconds},utc~:#{ts.inspect},ltz~:#{z.inspect})"
     end
@@ -240,7 +222,7 @@ def get_local_tzone(t)
 
       l = Time.local(t.year, t.month, t.day, t.hour, t.min, t.sec, t.usec)
 
-      t.zone == l.zone ? local_tzone : nil
+      (t.zone == l.zone) ? determine_local_tzone : nil
     end
 
     def get_as_tzone(t)
@@ -282,7 +264,7 @@ def get_tzone(o)
 
       def local_tzone
 
-        EtOrbi.local_tzone
+        EtOrbi.determine_local_tzone
       end
 
       def platform_info
@@ -302,7 +284,7 @@ def utc(*a)
 
       def local(*a)
 
-        EtOrbi.make_from_array(a, EtOrbi.local_tzone)
+        EtOrbi.make_from_array(a, local_tzone)
       end
     end
 
@@ -651,7 +633,7 @@ def determine_local_tzone
 
     def os_tz
 
-      debian_tz || centos_tz || osx_tz
+      @os_tz ||= (debian_tz || centos_tz || osx_tz)
     end
 
     #
@@ -707,7 +689,6 @@ def create_offset_tzone(utc_off, id)
         tzi.offset(id, utc_off, 0, id)
         tzi.create_timezone
       end
-
     end
 
     def determine_local_tzones
@@ -716,23 +697,24 @@ def determine_local_tzones
         .collect { |i| (Time.now + i * 30 * 24 * 3600).zone }
         .uniq
         .sort
+        .join('|')
 
       t = Time.now
       #tu = t.dup.utc # /!\ dup is necessary, #utc modifies its target
 
       twin = Time.utc(t.year, 1, 1) # winter
       tsum = Time.utc(t.year, 7, 1) # summer
 
-      ::TZInfo::Timezone.all.select do |tz|
+      @tz_all ||= ::TZInfo::Timezone.all
+      @tz_winter_summer ||= {}
 
-        pabbs =
-          [
-            tz.period_for_utc(twin).abbreviation.to_s,
-            tz.period_for_utc(tsum).abbreviation.to_s
-          ].uniq.sort
-
-        pabbs == tabbs
-      end
+      @tz_winter_summer[tabbs] ||= @tz_all
+        .select { |tz|
+          tabbs ==
+            [
+              tz.period_for_utc(twin).abbreviation.to_s,
+              tz.period_for_utc(tsum).abbreviation.to_s
+            ].uniq.sort.join('|') }
     end
 
     #

spec/module_spec.rb

@@ -309,7 +309,7 @@ def <=>(tz)
     end
   end
 
-  describe '.local_tzone' do
+  describe '.determine_local_tzone' do
 
     after :each do
 
@@ -320,13 +320,13 @@ class << self
       end rescue nil
     end
 
-    it 'caches and returns the local timezone' do
+    it 'returns the local timezone' do
 
       in_zone('Europe/Berlin') do
-        expect(EtOrbi.local_tzone.name).to eq('Europe/Berlin')
+        expect(EtOrbi.determine_local_tzone.name).to eq('Europe/Berlin')
       end
       in_zone('America/Jamaica') do
-        expect(EtOrbi.local_tzone.name).to eq('America/Jamaica')
+        expect(EtOrbi.determine_local_tzone.name).to eq('America/Jamaica')
       end
     end
 
@@ -344,12 +344,12 @@ def zone
       end
 
       in_zone(:no_env_tz) do
-        expect(EtOrbi.local_tzone.class).to eq(::TZInfo::DataTimezone)
-        expect(EtOrbi.local_tzone.name).to eq('Europe/Vilnius')
+        expect(EtOrbi.determine_local_tzone.class).to eq(::TZInfo::DataTimezone)
+        expect(EtOrbi.determine_local_tzone.name).to eq('Europe/Vilnius')
       end
       in_zone('Asia/Tehran') do
-        expect(EtOrbi.local_tzone.class).to eq(::TZInfo::DataTimezone)
-        expect(EtOrbi.local_tzone.name).to eq('Asia/Tehran')
+        expect(EtOrbi.determine_local_tzone.class).to eq(::TZInfo::DataTimezone)
+        expect(EtOrbi.determine_local_tzone.name).to eq('Asia/Tehran')
       end
     end
   end