Add first testing version of redditnews plugin

data/reddit-auth.json.example

+{
+  "username":"yourusername",
+  "password":"yourpassword"
+}

data/reddit-data.json.example

+{"follow":["/r/netsec"],"buffer":[]}

plugins/redditnews.rb

+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+# Plugin to announce new posts for selected subreddits
+# Requires "reddit-base" gem to be installed.
+class Redditnews
+  require 'json'
+  require 'reddit/base'
+
+  # This method is called when the plugin is first loaded
+  def initialize(status, config, output, irc, timer)
+    @status = status
+    @config = config
+    @output = output
+    @irc    = irc
+    @timer  = timer
+
+    # Plugin specific variables
+    @authfile = "#{@config.datadir}/reddit-auth.json"
+    @datafile = "#{@config.datadir}/reddit-data.json"
+    @follow   = []
+    @buffer   = []
+    @buffmax  = 100
+    @timeout  = 300
+    @channel  = '#news'
+
+    # Bootstrap and launch thread to fetch posts
+    load_data
+    @fthread = Thread.new { fetcher_thread }
+  end
+
+  # Method that will get called just before a plugin is unloaded/reloaded.
+  def unload
+    save_data
+    @fthread.exit
+    true
+  end
+
+  # Default method, called when no argument is given
+  def main(_nick, _user, _host, from, _msg, _arguments, _con)
+    @irc.message(from, "Please see 'redditnews help' for list of functions.")
+  end
+
+  # Function to send help about this plugin (Can also be called by the help plugin.)
+  def help(nick, _user, _host, _from, _msg, _arguments, con)
+    help = [
+      'Plugin to fetch reddit posts.',
+      '  redditnews following - List subreddits that are being followed.',
+      '  redditnews follow    - Add new subreddit to follow.',
+      '  redditnews unfollow  - Remove subreddit to follow.'
+    ]
+
+    # Print out help
+    help.each do |line|
+      if con
+        @output.c(line + "\n")
+      else
+        @irc.notice(nick, line)
+      end
+    end
+  end
+
+  # List subreddits being followed
+  def following(_nick, _user, _host, from, _msg, _arguments, _con)
+    @irc.message(from, "Following: #{@follow.join(', ')}.")
+  end
+
+  # Manage subreddits
+  def follow(_nick, _user, host, from, _msg, arguments, con)
+    if @config.auth(host, con)
+      if !arguments.nil? && !arguments.empty?
+        @follow.push arguments
+        save_data
+        line = "Added #{arguments}."
+      else
+        line = 'Expecting subreddit name to follow'
+      end
+      @irc.message(from, line)
+    end
+  end
+
+  def unfollow(_nick, _user, host, from, _msg, arguments, con)
+    if @config.auth(host, con)
+      if !arguments.nil? && !arguments.empty?
+        if @follow.include? arguments
+          @follow.delete arguments
+          line = "Removed #{arguments}."
+        else
+          line = "Already not following #{arguments}."
+        end
+      else
+        line = 'Expecting subreddit name to unfollow.'
+      end
+      @irc.message(from, line)
+    end
+  end
+
+  private
+
+  def start_client
+    conf = JSON.parse(File.read(@authfile))
+    Reddit::Base::Client.new(user: conf['username'], password: conf['password'])
+  end
+
+  # Load and save current state
+  def load_data
+    data = JSON.parse(File.read(@datafile))
+    @follow = data['follow']
+    @buffer = data['buffer']
+    data
+  end
+
+  def save_data
+    # Write @following and @buffer to @datafile
+    File.write(@datafile, ({ 'follow' => @follow, 'buffer' => @buffer }).to_json)
+  end
+
+  def fetcher_thread
+    client = start_client
+    loop do
+      begin
+        @follow.each do |subreddit|
+          resp = client.get subreddit
+          resp.body.data.children.each do |item|
+            if @buffer.include? item.data.id
+              # Purge from buffer so the most current recurring entries stay at the top
+              @buffer.delete item.data.id
+            else
+              # Appears to be a new post
+              @irc.message(@channel, "#{subreddit}: #{item.data.title} | #{item.data.url}")
+              @irc.message(@channel, ' ')
+            end
+            @buffer.push item.data.id
+
+            # Trim the cache buffer if it has gotten too big
+            @buffer.shift(@buffer.length - @buffmax) if @buffer.length > @buffmax
+          end
+        end
+        save_data
+      rescue
+        @out.debug('Failed to retreive subreddit posts')
+      end
+      sleep(@timeout)
+    end
+  end
+end