mephisto.rb

# frozen_string_literal: true

module JekyllImport
  module Importers
    class Mephisto < Importer
      # Accepts a hash with database config variables, exports mephisto posts into a csv
      # export PGPASSWORD if you must
      def self.postgres(c)
        sql = <<~SQL
          BEGIN;
          CREATE TEMP TABLE jekyll AS
            SELECT title, permalink, body, published_at, filter FROM contents
            WHERE user_id = 1 AND type = 'Article' ORDER BY published_at;
          COPY jekyll TO STDOUT WITH CSV HEADER;
          ROLLBACK;
        SQL
        command = %(psql -h #{c[:host] || "127.0.0.1"} -c "#{sql.strip}" #{c[:database]} #{c[:username]} -o #{c[:filename] || "posts.csv"})
        Jekyll.logger.info "Executing:", command
        `#{command}`
        CSV.process
      end

      def self.validate(options)
        %w(dbname user).each do |option|
          abort "Missing mandatory option --#{option}." if options[option].nil?
        end
      end

      def self.require_deps
        JekyllImport.require_with_fallback(%w(
          rubygems
          sequel
          mysql2
          csv
          fileutils
        ))
      end

      def self.specify_options(c)
        c.option "dbname",   "--dbname DB",   "Database name"
        c.option "user",     "--user USER",   "Database user name"
        c.option "password", "--password PW", "Database user's password (default: '')"
        c.option "host",     "--host HOST",   "Database host name (default: 'localhost')"
      end

      # This query will pull blog posts from all entries across all blogs. If
      # you've got unpublished, deleted or otherwise hidden posts please sift
      # through the created posts to make sure nothing is accidently published.
      QUERY = "SELECT id, \
                      permalink, \
                      body, \
                      published_at, \
                      title \
               FROM contents \
               WHERE user_id = 1 AND \
                     type = 'Article' AND \
                     published_at IS NOT NULL \
               ORDER BY published_at"

      def self.process(options)
        dbname = options.fetch("dbname")
        user   = options.fetch("user")
        pass   = options.fetch("password", "")
        host   = options.fetch("host", "127.0.0.1")

        db = Sequel.mysql2(dbname, :user     => user,
                                   :password => pass,
                                   :host     => host,
                                   :encoding => "utf8")

        FileUtils.mkdir_p "_posts"

        db[QUERY].each do |post|
          title = post[:title]
          slug = post[:permalink]
          date = post[:published_at]
          content = post[:body]

          # Ideally, this script would determine the post format (markdown,
          # html, etc) and create files with proper extensions. At this point
          # it just assumes that markdown will be acceptable.
          name = [date.year, date.month, date.day, slug].join("-") + ".markdown"

          data = {
            "layout" => "post",
            "title"  => title.to_s,
            "mt_id"  => post[:entry_id],
          }.delete_if { |_k, v| v.nil? || v == "" }.to_yaml

          File.open("_posts/#{name}", "w") do |f|
            f.puts data
            f.puts "---"
            f.puts content
          end
        end
      end
    end
  end
end