move_shards_out.rb

#!/usr/bin/ruby
require 'net/http'
require 'uri'
require 'json'

require 'optparse'
require 'io/console'

$stdout = File.new( '/var/log/move_shards_out.log', 'w' )

options = {:node_out => nil, :admin_password => nil  }

parser = OptionParser.new do|opts|
    opts.banner = "Usage: move_shards_out.rb [options]"
    opts.on('-o', '--node_out name1@fqdn/ip', 'Outgoing Node Name') do |node_out|
        options[:node_out] = node_out;
    end

    opts.on('-p', '--password password', 'Couch Admin Password') do |admin_password|
        options[:admin_password] = admin_password;
    end

    opts.on('-h', '--help', 'Displays Help') do
        puts opts
        exit
    end
end

parser.parse!

if options[:node_out] == nil
    print 'Enter Outgoing Node: '
    options[:node_out] = gets.chomp
end

if options[:admin_password] == nil
    print 'Enter Admin Password: '
    password = STDIN.noecho(&:gets).chomp
    print "\n"
else
    password = options[:admin_password]
end

admin_username = 'admin'
admin_password = password
node_out = options[:node_out] #"couchdb@10.0.1.252"


print admin_username
print admin_password
print node_out

def http_call (uri_string, username = '', password = '', data_json = {}, verb = 'Get')
    uri = URI.parse(uri_string)
    http = Net::HTTP.new(uri.host,uri.port)
	if verb == 'Put'
	  request = Net::HTTP::Put.new(uri.request_uri)
	  request.body = data_json
	else
	  request = Net::HTTP::Get.new(uri.request_uri)
	end
    request.basic_auth(username, password)
    response = http.request(request)
    response_json = JSON.parse response.body
end

all_dbs_response_json = http_call "http://127.0.0.1:5984/_all_dbs", admin_username, admin_password

all_dbs_response_json.each do |db|
  print "\n#{db}\n"
  info_about_db_response_json = http_call "http://127.0.0.1:5986/_dbs/#{db}", admin_username, admin_password

 #swap by_node information
  if info_about_db_response_json["by_node"].has_key? node_out
     info_about_db_response_json["by_node"].delete(node_out)
  else
     next
  end

  #replace outgoing nodes in each shard of by_range dictionary
  info_about_db_response_json["by_range"].each do |shard, nodes|
    if nodes.include? node_out
      nodes.delete(node_out)
    end
  end

  new_changelog = ["delete", node_out]
  info_about_db_response_json["changelog"].push(new_changelog)

  print JSON.pretty_generate(info_about_db_response_json)

  info_about_db_response_json_after = http_call "http://127.0.0.1:5986/_dbs/#{db}", admin_username, admin_password, info_about_db_response_json.to_json, 'Put'
  print JSON.pretty_generate(info_about_db_response_json_after)
end

$stdout.close()