add proof of concept sftp downloader

Gemfile

@@ -55,6 +55,9 @@ gem 'stimulus-rails'
 gem 'watir'
 
 gem 'selenium-webdriver', '~> 4.4'
+gem 'net-sftp'
+gem 'ed25519'
+gem 'bcrypt_pbkdf'
 
 group :development, :test do
   # Call 'byebug' anywhere in the code to stop execution and get a debugger console

Gemfile.lock

@@ -82,6 +82,7 @@ GEM
     ast (2.4.2)
     backport (1.2.0)
     bcrypt (3.1.18)
+    bcrypt_pbkdf (1.1.0)
     benchmark (0.2.0)
     better_html (1.0.16)
       actionview (>= 4.0)
@@ -132,6 +133,7 @@ GEM
     diff-lcs (1.5.0)
     docile (1.4.0)
     e2mmap (0.1.0)
+    ed25519 (1.3.0)
     erb_lint (0.1.3)
       activesupport
       better_html (~> 1.0.7)
@@ -204,8 +206,11 @@ GEM
       net-protocol
     net-protocol (0.1.3)
       timeout
+    net-sftp (4.0.0)
+      net-ssh (>= 5.0.0, < 8.0.0)
     net-smtp (0.3.3)
       net-protocol
+    net-ssh (7.0.1)
     newrelic_rpm (8.8.0)
     nio4r (2.5.8)
     nokogiri (1.13.10)
@@ -408,6 +413,7 @@ PLATFORMS
 DEPENDENCIES
   activerecord-import
   apparition!
+  bcrypt_pbkdf
   bootsnap
   brakeman
   bullet
@@ -417,6 +423,7 @@ DEPENDENCIES
   database_cleaner
   debug
   devise
+  ed25519
   erb_lint
   erblint-github
   factory_bot_rails
@@ -428,6 +435,7 @@ DEPENDENCIES
   launchy
   listen (~> 3.0.5)
   nested_scaffold
+  net-sftp
   newrelic_rpm
   nokogiri (>= 1.13.4)
   omniauth

app/services/sftp/downloader.rb

@@ -0,0 +1,26 @@
+require 'net/sftp'
+require 'uri'
+require 'csv'
+
+module Sftp
+  class Downloader
+    def initialize
+      sftptogo_url = ENV['SFTPTOGO_URL']
+      uri = URI.parse(sftptogo_url)
+      Net::SFTP.start(uri.host, uri.user, password: uri.password) do |sftp|
+        # download a file or directory from the remote host
+        # open and read from a pseudo-IO for a remote file
+        # sftp.file.open('/mciea/data/canary.csv', 'r') do |f|
+        #   CSV.parse(f.read) do |row|
+        #     puts row
+        #   end
+        # end
+
+        # list the entries in a directory
+        sftp.dir.foreach('/mciea/data/') do |entry|
+          puts entry.longname
+        end
+      end
+    end
+  end
+end