Allow unlimited tries

.gitignore

@@ -1,6 +1,5 @@
 /.bundle/
 /.yardoc
-/Gemfile.lock
 /_yardoc/
 /coverage/
 /doc/

.rubocop.yml

@@ -1,3 +1,7 @@
+inherit_from: .rubocop_todo.yml
+AllCops:
+  TargetRubyVersion: 2.0
+
 Style/StringLiterals:
   EnforcedStyle: double_quotes
 

.rubocop_todo.yml

@@ -0,0 +1,21 @@
+# This configuration was generated by
+# `rubocop --auto-gen-config`
+# on 2020-12-28 23:59:17 -0500 using RuboCop version 0.50.0.
+# The point is for the user to remove these configuration records
+# one by one as the offenses are removed from the code base.
+# Note that changes in the inspected code, or installation of new
+# versions of RuboCop, may require this file to be generated again.
+
+# Offense count: 1
+Metrics/CyclomaticComplexity:
+  Max: 14
+
+# Offense count: 2
+# Configuration parameters: AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, IgnoredPatterns.
+# URISchemes: http, https
+Metrics/LineLength:
+  Max: 202
+
+# Offense count: 1
+Metrics/PerceivedComplexity:
+  Max: 15

Gemfile

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 source "https://rubygems.org"
 
 gemspec
@@ -8,7 +10,8 @@ group :test do
 end
 
 group :development do
-  gem "rubocop"
+  gem "rubocop", ">= 0.50", "< 0.51", require: false
+  gem "rubocop-rspec", require: false
 end
 
 group :development, :test do

Gemfile.lock

@@ -0,0 +1,68 @@
+PATH
+  remote: .
+  specs:
+    retriable (3.1.2)
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    ast (2.4.2)
+    coderay (1.1.3)
+    diff-lcs (1.4.4)
+    docile (1.3.5)
+    json (2.5.1)
+    method_source (1.0.0)
+    parallel (1.13.0)
+    parser (2.7.2.0)
+      ast (~> 2.4.1)
+    powerpack (0.1.3)
+    pry (0.13.1)
+      coderay (~> 1.1)
+      method_source (~> 1.0)
+    rainbow (2.2.2)
+      rake
+    rake (12.3.3)
+    rspec (3.10.0)
+      rspec-core (~> 3.10.0)
+      rspec-expectations (~> 3.10.0)
+      rspec-mocks (~> 3.10.0)
+    rspec-core (3.10.1)
+      rspec-support (~> 3.10.0)
+    rspec-expectations (3.10.1)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.10.0)
+    rspec-mocks (3.10.1)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.10.0)
+    rspec-support (3.10.1)
+    rubocop (0.50.0)
+      parallel (~> 1.10)
+      parser (>= 2.3.3.1, < 3.0)
+      powerpack (~> 0.1)
+      rainbow (>= 2.2.2, < 3.0)
+      ruby-progressbar (~> 1.7)
+      unicode-display_width (~> 1.0, >= 1.0.1)
+    rubocop-rspec (1.5.1)
+      rubocop (>= 0.41.2)
+    ruby-progressbar (1.11.0)
+    simplecov (0.17.1)
+      docile (~> 1.1)
+      json (>= 1.8, < 3)
+      simplecov-html (~> 0.10.0)
+    simplecov-html (0.10.2)
+    unicode-display_width (1.7.0)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  bundler
+  pry
+  retriable!
+  rspec
+  rubocop (>= 0.50, < 0.51)
+  rubocop-rspec
+  simplecov
+
+BUNDLED WITH
+   1.17.3

lib/retriable.rb

@@ -42,35 +42,54 @@ def retriable(opts = {})
     elapsed_time = -> { Time.now - start_time }
 
     if intervals
-      tries = intervals.size + 1
+      tries = intervals.size + 1 if intervals.size
     else
-      intervals = ExponentialBackoff.new(
-        tries:          tries - 1,
+      backoff = ExponentialBackoff.new(
+        tries:          tries ? tries - 1 : nil,
         base_interval:  base_interval,
         multiplier:     multiplier,
         max_interval:   max_interval,
-        rand_factor:    rand_factor
-      ).intervals
+        rand_factor:    rand_factor,
+      )
+      intervals = backoff.intervals
     end
 
-    tries.times do |index|
-      try = index + 1
-
+    # TODO: Ideally this would be it's own function, but would probably require
+    #   a separate class to efficiently pass on the processed config
+    run_try = Proc.new do |interval, try|
       begin
         return Timeout.timeout(timeout) { return yield(try) } if timeout
         return yield(try)
-      rescue *[*exception_list] => exception
+      rescue *exception_list => exception
         if on.is_a?(Hash)
           raise unless exception_list.any? do |e|
             exception.is_a?(e) && ([*on[e]].empty? || [*on[e]].any? { |pattern| exception.message =~ pattern })
           end
         end
-
-        interval = intervals[index]
         on_retry.call(exception, try, elapsed_time.call, interval) if on_retry
-        raise if try >= tries || (elapsed_time.call + interval) > max_elapsed_time
-        sleep interval if sleep_disabled != true
+
+
+        # Note: Tries can't always be calculated if a custom Enumerator is given
+        #   for the intervals argument. (Enumerator#size will return nil, per docs)
+        #   So we'll just let the enumerator run out, and then invoke run_try once more.
+        #   With a nil timeout.
+        raise unless interval
+        raise if max_elapsed_time && elapsed_time.call + interval > max_elapsed_time
+        sleep interval unless sleep_disabled
+        throw :failed
+      end
+    end
+
+    try = 0
+    intervals.each do |interval|
+      try += 1
+      # Use throw/catch to distinguish between success and caught exception
+      catch :failed do
+        result = run_try.call(interval, try)
+        return result
       end
+      break if tries and try + 1 >= tries
     end
+    run_try.call(nil, try + 1)
   end
 end

lib/retriable/config.rb

@@ -2,15 +2,15 @@
 
 module Retriable
   class Config
-    ATTRIBUTES = (ExponentialBackoff::ATTRIBUTES + [
-      :sleep_disabled,
-      :max_elapsed_time,
-      :intervals,
-      :timeout,
-      :on,
-      :on_retry,
-      :contexts,
-    ]).freeze
+    ATTRIBUTES = (ExponentialBackoff::ATTRIBUTES + %i[
+sleep_disabled
+max_elapsed_time
+intervals
+timeout
+on
+on_retry
+contexts
+]).freeze
 
     attr_accessor(*ATTRIBUTES)
 

lib/retriable/exponential_backoff.rb

@@ -1,12 +1,12 @@
 module Retriable
   class ExponentialBackoff
-    ATTRIBUTES = [
-      :tries,
-      :base_interval,
-      :multiplier,
-      :max_interval,
-      :rand_factor,
-    ].freeze
+    ATTRIBUTES = %i[
+tries
+base_interval
+multiplier
+max_interval
+rand_factor
+].freeze
 
     attr_accessor(*ATTRIBUTES)
 
@@ -24,18 +24,22 @@ def initialize(opts = {})
     end
 
     def intervals
-      intervals = Array.new(tries) do |iteration|
-        [base_interval * multiplier**iteration, max_interval].min
-      end
-
-      return intervals if rand_factor.zero?
-
-      intervals.map { |i| randomize(i) }
+      Enumerator.new(tries) do |result|
+        try = 0
+        loop do
+          interval = [base_interval * multiplier**try, max_interval].min
+          result << randomize(interval)
+          try += 1
+          raise StopIteration if tries && try >= tries
+        end
+      end.lazy
     end
 
     private
 
     def randomize(interval)
+      return interval if rand_factor.zero?
+
       delta = rand_factor * interval * 1.0
       min = interval - delta
       max = interval + delta

retriable.gemspec

@@ -1,4 +1,4 @@
-# coding: utf-8
+
 lib = File.expand_path("../lib", __FILE__)
 $LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
 require "retriable/version"
@@ -23,10 +23,4 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency "bundler"
   spec.add_development_dependency "rspec", "~> 3"
 
-  if RUBY_VERSION < "2.3"
-    spec.add_development_dependency "ruby_dep", "~> 1.3.1"
-    spec.add_development_dependency "listen", "~> 3.0.8"
-  else
-    spec.add_development_dependency "listen", "~> 3.1"
-  end
 end

spec/exponential_backoff_spec.rb

@@ -20,7 +20,7 @@
   end
 
   it "generates 10 randomized intervals" do
-    expect(described_class.new(tries: 9).intervals).to eq([
+    expect(described_class.new(tries: 9).intervals.to_a).to eq([
       0.5244067512211441,
       0.9113920238761231,
       1.2406087918999114,
@@ -29,7 +29,7 @@
       4.350816718580626,
       5.339852157217869,
       11.889873261212443,
-      18.756037881636484,
+      18.756037881636484
     ])
   end
 
@@ -38,35 +38,35 @@
   end
 
   it "generates intervals with a defined base interval" do
-    expect(described_class.new(base_interval: 1).intervals).to eq([
+    expect(described_class.new(base_interval: 1).intervals.to_a).to eq([
       1.0488135024422882,
       1.8227840477522461,
-      2.4812175837998227,
+      2.4812175837998227
     ])
   end
 
   it "generates intervals with a defined multiplier" do
-    expect(described_class.new(multiplier: 1).intervals).to eq([
+    expect(described_class.new(multiplier: 1).intervals.to_a).to eq([
       0.5244067512211441,
       0.607594682584082,
-      0.5513816852888495,
+      0.5513816852888495
     ])
   end
 
   it "generates intervals with a defined max interval" do
-    expect(described_class.new(max_interval: 1.0, rand_factor: 0.0).intervals).to eq([0.5, 0.75, 1.0])
+    expect(described_class.new(max_interval: 1.0, rand_factor: 0.0).intervals.to_a).to eq([0.5, 0.75, 1.0])
   end
 
   it "generates intervals with a defined rand_factor" do
-    expect(described_class.new(rand_factor: 0.2).intervals).to eq([
+    expect(described_class.new(rand_factor: 0.2).intervals.to_a).to eq([
       0.5097627004884576,
       0.8145568095504492,
-      1.1712435167599646,
+      1.1712435167599646
     ])
   end
 
   it "generates 10 non-randomized intervals" do
     non_random_intervals = 9.times.inject([0.5]) { |memo, _i| memo + [memo.last * 1.5] }
-    expect(described_class.new(tries: 10, rand_factor: 0.0).intervals).to eq(non_random_intervals)
+    expect(described_class.new(tries: 10, rand_factor: 0.0).intervals.to_a).to eq(non_random_intervals)
   end
 end