diff --git a/lib/github_changelog_generator.rb b/lib/github_changelog_generator.rb
index 2832dce..dd8c71c 100755
--- a/lib/github_changelog_generator.rb
+++ b/lib/github_changelog_generator.rb
@@ -9,6 +9,7 @@ require_relative "github_changelog_generator/parser"
 require_relative "github_changelog_generator/generator"
 require_relative "github_changelog_generator/version"
 require_relative "github_changelog_generator/reader"
+require_relative "github_changelog_generator/fetcher"
 
 module GitHubChangelogGenerator
   # Default error for ChangelogGenerator
@@ -19,33 +20,19 @@ module GitHubChangelogGenerator
   class ChangelogGenerator
     attr_accessor :options, :all_tags, :github
 
-    PER_PAGE_NUMBER = 30
-    GH_RATE_LIMIT_EXCEEDED_MSG = "Warning: GitHub API rate limit (5000 per hour) exceeded, change log may be " \
-        "missing some issues. You can limit the number of issues fetched using the `--max-issues NUM` argument."
-
     # Class, responsible for whole change log generation cycle
-    # @return initialised insance of ChangelogGenerator
+    # @return initialised instance of ChangelogGenerator
     def initialize
       @options = Parser.parse_options
 
-      fetch_github_token
+      @fetcher = GitHubChangelogGenerator::Fetcher.new @options
 
-      github_options = { per_page: PER_PAGE_NUMBER }
-      github_options[:oauth_token] = @github_token unless @github_token.nil?
-      github_options[:endpoint] = options[:github_endpoint] unless options[:github_endpoint].nil?
-      github_options[:site] = options[:github_endpoint] unless options[:github_site].nil?
+      @generator = Generator.new @options
 
-      begin
-        @github = Github.new github_options
-      rescue
-        puts GH_RATE_LIMIT_EXCEEDED_MSG.yellow
-      end
+      # @all_tags = get_filtered_tags
+      @all_tags = @fetcher.get_all_tags
 
-      @generator = Generator.new(@options)
-
-      @all_tags = get_all_tags
-
-      @issues, @pull_requests = fetch_issues_and_pull_requests
+      @issues, @pull_requests = @fetcher.fetch_issues_and_pull_requests
 
       @pull_requests = @options[:pulls] ? get_filtered_pull_requests : []
 
@@ -53,7 +40,23 @@ module GitHubChangelogGenerator
 
       fetch_event_for_issues_and_pr
       detect_actual_closed_dates
-      @tag_times_hash = {}
+    end
+
+    # Return tags after filtering tags in lists provided by option: --between-tags & --exclude-tags
+    #
+    # @return [Array]
+    def get_filtered_tags
+      all_tags = @fetcher.get_all_tags
+      filtered_tags = []
+      if @options[:between_tags]
+        @options[:between_tags].each do |tag|
+          unless all_tags.include? tag
+            puts "Warning: can't find tag #{tag}, specified with --between-tags option.".yellow
+          end
+        end
+        filtered_tags = all_tags.select { |tag| @options[:between_tags].include? tag }
+      end
+      filtered_tags
     end
 
     def detect_actual_closed_dates
@@ -81,6 +84,8 @@ module GitHubChangelogGenerator
       end
     end
 
+    # Fill :actual_date parameter of specified issue by closed date of the commit, it it was closed by commit.
+    # @param [Hash] issue
     def find_closed_date_by_commit(issue)
       unless issue["events"].nil?
         # if it's PR -> then find "merged event", in case of usual issue -> fond closed date
@@ -92,7 +97,7 @@ module GitHubChangelogGenerator
               issue[:actual_date] = issue[:closed_at]
             else
               begin
-                commit = @github.git_data.commits.get @options[:user], @options[:project], event[:commit_id]
+                commit = @fetcher.fetch_commit(event)
                 issue[:actual_date] = commit[:author][:date]
               rescue
                 puts "Warning: Can't fetch commit #{event[:commit_id]}. It is probably referenced from another repo.".yellow
@@ -110,42 +115,6 @@ module GitHubChangelogGenerator
       puts JSON.pretty_generate(json)
     end
 
-    # This method fetch missing required attributes for pull requests
-    # :merged_at - is a date, when issue PR was merged.
-    # More correct to use this date, not closed date.
-    def fetch_merged_at_pull_requests
-      if @options[:verbose]
-        print "Fetching merged dates...\r"
-      end
-      pull_requests = []
-      begin
-        response = @github.pull_requests.list @options[:user], @options[:project], state: "closed"
-        page_i = 0
-        response.each_page do |page|
-          page_i += PER_PAGE_NUMBER
-          count_pages = response.count_pages
-          print "Fetching merged dates... #{page_i}/#{count_pages * PER_PAGE_NUMBER}\r"
-          pull_requests.concat(page)
-        end
-      rescue
-        puts GH_RATE_LIMIT_EXCEEDED_MSG.yellow
-      end
-
-      print "                                                   \r"
-
-      @pull_requests.each { |pr|
-        fetched_pr = pull_requests.find { |fpr|
-          fpr.number == pr.number
-        }
-        pr[:merged_at] = fetched_pr[:merged_at]
-        pull_requests.delete(fetched_pr)
-      }
-
-      if @options[:verbose]
-        puts "Fetching merged dates: Done!"
-      end
-    end
-
     # This method fetches missing params for PR and filter them by specified options
     # It include add all PR's with labels from @options[:include_labels] array
     # And exclude all from :exclude_labels array.
@@ -164,6 +133,28 @@ module GitHubChangelogGenerator
       filtered_pull_requests
     end
 
+    # This method fetch missing required attributes for pull requests
+    # :merged_at - is a date, when issue PR was merged.
+    # More correct to use this date, not closed date.
+    def fetch_merged_at_pull_requests
+      if @options[:verbose]
+        print "Fetching merged dates...\r"
+      end
+      pull_requests = @fetcher.fetch_pull_requests
+
+      @pull_requests.each { |pr|
+        fetched_pr = pull_requests.find { |fpr|
+          fpr.number == pr.number
+        }
+        pr[:merged_at] = fetched_pr[:merged_at]
+        pull_requests.delete(fetched_pr)
+      }
+
+      if @options[:verbose]
+        puts "Fetching merged dates: Done!"
+      end
+    end
+
     # Include issues with labels, specified in :include_labels
     # @param [Array] issues to filter
     # @return [Array] filtered array of issues
@@ -238,7 +229,7 @@ module GitHubChangelogGenerator
         puts "Sorting tags..."
       end
 
-      @all_tags.sort_by! { |x| get_time_of_tag(x) }.reverse!
+      @all_tags.sort_by! { |x| @fetcher.get_time_of_tag(x) }.reverse!
 
       if @options[:verbose]
         puts "Generating log..."
@@ -274,9 +265,8 @@ module GitHubChangelogGenerator
       i = 0
       all = @all_tags.count
       @all_tags.each { |tag|
-        # explicit set @tag_times_hash to write data safety.
         threads << Thread.new {
-          get_time_of_tag(tag, @tag_times_hash)
+          @fetcher.get_time_of_tag(tag)
           if @options[:verbose]
             print "Fetching tags dates: #{i + 1}/#{all}\r"
             i += 1
@@ -293,48 +283,6 @@ module GitHubChangelogGenerator
       end
     end
 
-    def get_all_tags
-      if @options[:verbose]
-        print "Fetching tags...\r"
-      end
-
-      tags = []
-
-      begin
-        response = @github.repos.tags @options[:user], @options[:project]
-        page_i = 0
-        count_pages = response.count_pages
-        response.each_page do |page|
-          page_i += PER_PAGE_NUMBER
-          print "Fetching tags... #{page_i}/#{count_pages * PER_PAGE_NUMBER}\r"
-          tags.concat(page)
-        end
-        print "                               \r"
-
-        if tags.count == 0
-          puts "Warning: Can't find any tags in repo. Make sure, that you push tags to remote repo via 'git push --tags'".yellow
-        elsif @options[:verbose]
-          puts "Found #{tags.count} tags"
-        end
-
-      rescue
-        puts GH_RATE_LIMIT_EXCEEDED_MSG.yellow
-      end
-
-      tags
-    end
-
-    def fetch_github_token
-      env_var = @options[:token] ? @options[:token] : (ENV.fetch "CHANGELOG_GITHUB_TOKEN", nil)
-
-      unless env_var
-        puts "Warning: No token provided (-t option) and variable $CHANGELOG_GITHUB_TOKEN was not found.".yellow
-        puts "This script can make only 50 requests per hour to GitHub API without a token!".yellow
-      end
-
-      @github_token ||= env_var
-    end
-
     # Generate log only between 2 specified tags
     # @param [String] older_tag all issues before this tag date will be excluded. May be nil, if it's first tag
     # @param [String] newer_tag all issue after this tag will be excluded. May be nil for unreleased section
@@ -403,8 +351,8 @@ module GitHubChangelogGenerator
     def delete_by_time(array, hash_key = :actual_date, older_tag = nil, newer_tag = nil)
       fail ChangelogGeneratorError, "At least one of the tags should be not nil!".red if older_tag.nil? && newer_tag.nil?
 
-      newer_tag_time = newer_tag && get_time_of_tag(newer_tag)
-      older_tag_time = older_tag && get_time_of_tag(older_tag)
+      newer_tag_time = newer_tag && @fetcher.get_time_of_tag(newer_tag)
+      older_tag_time = older_tag && @fetcher.get_time_of_tag(older_tag)
 
       array.select { |req|
         if req[hash_key]
@@ -439,9 +387,9 @@ module GitHubChangelogGenerator
     # @param [String] older_tag_name Older tag, used for the links. Could be nil for last tag.
     # @return [String] Ready and parsed section
     def create_log(pull_requests, issues, newer_tag, older_tag_name = nil)
-      newer_tag_time = newer_tag.nil? ? Time.new                    : get_time_of_tag(newer_tag)
+      newer_tag_time = newer_tag.nil? ? Time.new : @fetcher.get_time_of_tag(newer_tag)
       newer_tag_name = newer_tag.nil? ? @options[:unreleased_label] : newer_tag["name"]
-      newer_tag_link = newer_tag.nil? ? "HEAD"                      : newer_tag_name
+      newer_tag_link = newer_tag.nil? ? "HEAD" : newer_tag_name
 
       github_site = options[:github_site] || "https://github.com"
       project_url = "#{github_site}/#{@options[:user]}/#{@options[:project]}"
@@ -534,27 +482,8 @@ module GitHubChangelogGenerator
       log
     end
 
-    # Try to find tag date in local hash.
-    # Otherwise fFetch tag time and put it to local hash file.
-    # @param [String] tag_name name of the tag
-    # @param [Hash] tag_times_hash the hash of tag times
-    # @return [Time] time of specified tag
-    def get_time_of_tag(tag_name, tag_times_hash = @tag_times_hash)
-      fail ChangelogGeneratorError, "tag_name is nil".red if tag_name.nil?
-
-      if tag_times_hash[tag_name["name"]]
-        return @tag_times_hash[tag_name["name"]]
-      end
-
-      begin
-        github_git_data_commits_get = @github.git_data.commits.get @options[:user], @options[:project], tag_name["commit"]["sha"]
-      rescue
-        puts GH_RATE_LIMIT_EXCEEDED_MSG.yellow
-      end
-      time_string = github_git_data_commits_get["committer"]["date"]
-      @tag_times_hash[tag_name["name"]] = Time.parse(time_string)
-    end
-
+    # Filter issues according labels
+    # @return [Array] Filtered issues
     def get_filtered_issues
       filtered_issues = include_issues_by_labels(@issues)
 
@@ -567,41 +496,8 @@ module GitHubChangelogGenerator
       filtered_issues
     end
 
-    # This method fetch all closed issues and separate them to pull requests and pure issues
-    # (pull request is kind of issue in term of GitHub)
-    # @return [Tuple] with issues and pull requests
-    def fetch_issues_and_pull_requests
-      if @options[:verbose]
-        print "Fetching closed issues...\r"
-      end
-      issues = []
-
-      begin
-        response = @github.issues.list user: @options[:user], repo: @options[:project], state: "closed", filter: "all", labels: nil
-        page_i = 0
-        count_pages = response.count_pages
-        response.each_page do |page|
-          page_i += PER_PAGE_NUMBER
-          print "Fetching issues... #{page_i}/#{count_pages * PER_PAGE_NUMBER}\r"
-          issues.concat(page)
-          break if @options[:max_issues] && issues.length >= @options[:max_issues]
-        end
-      rescue
-        puts GH_RATE_LIMIT_EXCEEDED_MSG.yellow
-      end
-
-      print "                                                \r"
-
-      if @options[:verbose]
-        puts "Received issues: #{issues.count}"
-      end
-
-      # remove pull request from issues:
-      issues.partition { |x|
-        x[:pull_request].nil?
-      }
-    end
-
+    # Fetch event for issues and pull requests
+    # @return [Array] array of fetched issues
     def fetch_event_for_issues_and_pr
       if @options[:verbose]
         print "Fetching events for issues and PR: 0/#{@issues.count + @pull_requests.count}\r"
@@ -609,36 +505,7 @@ module GitHubChangelogGenerator
 
       # Async fetching events:
 
-      fetch_events_async(@issues + @pull_requests)
-    end
-
-    def fetch_events_async(issues)
-      i = 0
-      max_thread_number = 50
-      threads = []
-      issues.each_slice(max_thread_number) { |issues_slice|
-        issues_slice.each { |issue|
-          threads << Thread.new {
-            begin
-              obj = @github.issues.events.list user: @options[:user], repo: @options[:project], issue_number: issue["number"]
-            rescue
-              puts GH_RATE_LIMIT_EXCEEDED_MSG.yellow
-            end
-            issue[:events] = obj.body
-            print "Fetching events for issues and PR: #{i + 1}/#{@issues.count + @pull_requests.count}\r"
-            i += 1
-          }
-        }
-        threads.each(&:join)
-        threads = []
-      }
-
-      # to clear line from prev print
-      print "                                                            \r"
-
-      if @options[:verbose]
-        puts "Fetching events for issues and PR: #{i} Done!"
-      end
+      @fetcher.fetch_events_async(@issues + @pull_requests)
     end
   end
 
diff --git a/lib/github_changelog_generator/fetcher.rb b/lib/github_changelog_generator/fetcher.rb
new file mode 100644
index 0000000..f83da19
--- /dev/null
+++ b/lib/github_changelog_generator/fetcher.rb
@@ -0,0 +1,209 @@
+require "logger"
+
+module GitHubChangelogGenerator
+  # A Fetcher responsible for all requests to GitHub and all basic manipulation with related data
+  # (such as filtering, validating, e.t.c)
+  #
+  # Example:
+  # fetcher = GitHubChangelogGenerator::Fetcher.new options
+  class Fetcher
+    PER_PAGE_NUMBER = 30
+    GH_RATE_LIMIT_EXCEEDED_MSG = "Warning: GitHub API rate limit (5000 per hour) exceeded, change log may be " \
+        "missing some issues. You can limit the number of issues fetched using the `--max-issues NUM` argument."
+
+    def initialize(options = {})
+      @options = options
+
+      @user = @options[:user]
+      @project = @options[:project]
+      @github_token = fetch_github_token
+      @tag_times_hash = {}
+
+      @logger = Logger.new(STDOUT)
+      @logger.formatter = proc do |_severity, _datetime, _progname, msg|
+        "#{msg}\n"
+      end
+      github_options = { per_page: PER_PAGE_NUMBER }
+      github_options[:oauth_token] = @github_token unless @github_token.nil?
+      github_options[:endpoint] = options[:github_endpoint] unless options[:github_endpoint].nil?
+      github_options[:site] = options[:github_endpoint] unless options[:github_site].nil?
+
+      begin
+        @github = Github.new github_options
+      rescue
+        @logger.warn GH_RATE_LIMIT_EXCEEDED_MSG.yellow
+      end
+    end
+
+    # Returns GitHub token. First try to use variable, provided by --token option,
+    # otherwise try to fetch it from CHANGELOG_GITHUB_TOKEN env variable.
+    #
+    # @return [String]
+    def fetch_github_token
+      env_var = @options[:token] ? @options[:token] : (ENV.fetch "CHANGELOG_GITHUB_TOKEN", nil)
+
+      unless env_var
+        @logger.warn "Warning: No token provided (-t option) and variable $CHANGELOG_GITHUB_TOKEN was not found.".yellow
+        @logger.warn "This script can make only 50 requests to GitHub API per hour without token!".yellow
+      end
+
+      env_var
+    end
+
+    # Fetch all tags from repo
+    # @return [Array] array of tags
+    def get_all_tags
+      if @options[:verbose]
+        print "Fetching tags...\r"
+      end
+
+      tags = []
+
+      begin
+        response = @github.repos.tags @options[:user], @options[:project]
+        page_i = 0
+        count_pages = response.count_pages
+        response.each_page do |page|
+          page_i += PER_PAGE_NUMBER
+          print "Fetching tags... #{page_i}/#{count_pages * PER_PAGE_NUMBER}\r"
+          tags.concat(page)
+        end
+        print "                               \r"
+
+        if tags.count == 0
+          @logger.warn "Warning: Can't find any tags in repo.\
+Make sure, that you push tags to remote repo via 'git push --tags'".yellow
+        elsif @options[:verbose]
+          @logger.info "Found #{tags.count} tags"
+        end
+
+      rescue
+        @logger.warn GH_RATE_LIMIT_EXCEEDED_MSG.yellow
+      end
+
+      tags
+    end
+
+    # This method fetch all closed issues and separate them to pull requests and pure issues
+    # (pull request is kind of issue in term of GitHub)
+    # @return [Tuple] with issues and pull requests
+    def fetch_issues_and_pull_requests
+      if @options[:verbose]
+        print "Fetching closed issues...\r"
+      end
+      issues = []
+
+      begin
+        response = @github.issues.list user: @options[:user],
+                                       repo: @options[:project],
+                                       state: "closed",
+                                       filter: "all",
+                                       labels: nil
+        page_i = 0
+        count_pages = response.count_pages
+        response.each_page do |page|
+          page_i += PER_PAGE_NUMBER
+          print "Fetching issues... #{page_i}/#{count_pages * PER_PAGE_NUMBER}\r"
+          issues.concat(page)
+          break if @options[:max_issues] && issues.length >= @options[:max_issues]
+        end
+      rescue
+        @logger.warn GH_RATE_LIMIT_EXCEEDED_MSG.yellow
+      end
+
+      print "                                                \r"
+
+      if @options[:verbose]
+        @logger.info "Received issues: #{issues.count}"
+      end
+
+      # remove pull request from issues:
+      issues.partition { |x|
+        x[:pull_request].nil?
+      }
+    end
+
+    # Fetch all pull requests. We need them to detect :merged_at parameter
+    # @return [Array] all pull requests
+    def fetch_pull_requests
+      pull_requests = []
+      begin
+        response = @github.pull_requests.list @options[:user], @options[:project], state: "closed"
+        page_i = 0
+        response.each_page do |page|
+          page_i += PER_PAGE_NUMBER
+          count_pages = response.count_pages
+          print "Fetching merged dates... #{page_i}/#{count_pages * PER_PAGE_NUMBER}\r"
+          pull_requests.concat(page)
+        end
+      rescue
+        @logger.warn GH_RATE_LIMIT_EXCEEDED_MSG.yellow
+      end
+
+      print "                                                   \r"
+      pull_requests
+    end
+
+    # Fetch event for all issues and add them to :events
+    # @param [Array] issues
+    # @return [Void]
+    def fetch_events_async(issues)
+      i = 0
+      max_thread_number = 50
+      threads = []
+      issues.each_slice(max_thread_number) { |issues_slice|
+        issues_slice.each { |issue|
+          threads << Thread.new {
+            begin
+              obj = @github.issues.events.list user: @options[:user],
+                                               repo: @options[:project],
+                                               issue_number: issue["number"]
+            rescue
+              @logger.warn GH_RATE_LIMIT_EXCEEDED_MSG.yellow
+            end
+            issue[:events] = obj.body
+            print "Fetching events for issues and PR: #{i + 1}/#{issues.count}\r"
+            i += 1
+          }
+        }
+        threads.each(&:join)
+        threads = []
+      }
+
+      # to clear line from prev print
+      print "                                                            \r"
+
+      if @options[:verbose]
+        @logger.info "Fetching events for issues and PR: #{i} Done!"
+      end
+    end
+
+    # Try to find tag date in local hash.
+    # Otherwise fFetch tag time and put it to local hash file.
+    # @param [String] tag_name name of the tag
+    # @return [Time] time of specified tag
+    def get_time_of_tag(tag_name)
+      fail ChangelogGeneratorError, "tag_name is nil".red if tag_name.nil?
+
+      if @tag_times_hash[tag_name["name"]]
+        return @tag_times_hash[tag_name["name"]]
+      end
+
+      begin
+        github_git_data_commits_get = @github.git_data.commits.get @options[:user],
+                                                                   @options[:project],
+                                                                   tag_name["commit"]["sha"]
+      rescue
+        @logger.warn GH_RATE_LIMIT_EXCEEDED_MSG.yellow
+      end
+      time_string = github_git_data_commits_get["committer"]["date"]
+      @tag_times_hash[tag_name["name"]] = Time.parse(time_string)
+    end
+
+    # Fetch commit for specifed event
+    # @return [Hash]
+    def fetch_commit(event)
+      @github.git_data.commits.get @options[:user], @options[:project], event[:commit_id]
+    end
+  end
+end