Class: Cassandro::Migrator

Inherits:
Object
  • Object
show all
Defined in:
lib/cassandro/ext/migrator.rb

Defined Under Namespace

Classes: CassandroMigration

Instance Method Summary collapse

Constructor Details

#initialize(path, logger = ::Logger.new(STDOUT)) ⇒ Migrator

Returns a new instance of Migrator.


6
7
8
9
10
11
12
13
14
15
16
 
# File 'lib/cassandro/ext/migrator.rb', line 6

def initialize(path, logger = ::Logger.new(STDOUT))
  Dir["#{path}/**/*.rb"].each { |file| require file }
  @migrations = Cassandro::Migration.migrations
  @logger = logger

  Cassandro.client.execute CassandroMigration.schema

  version = CassandroMigration[name: 'version'] || CassandroMigration.create(name: 'version', value: "0")

  @current_version = version
end

Instance Method Details

#migrate!(direction, to = '.') ⇒ Object 


18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
 
# File 'lib/cassandro/ext/migrator.rb', line 18

def migrate!(direction, to = '.')
  from = @current_version.value.to_i

  case direction
  when :up
    to   = (to == '.' ? @migrations.size - 1 : to).to_i
    return @logger.error "Can't migrate up to a prev version (#{from} to #{to})" if to < from
    return @logger.info  "Database is up to date" if to == from

    @logger.info "Upgrading database from version #{from} to #{to}"
    begin
      @migrations[from+1..to].each do |migration|
        Object.const_get(migration).apply(:up)
      end
      @current_version.update_attributes(value: to.to_s)
      @logger.info "OK"
    rescue => e
      @logger.error "#{e.message}\n#{e.backtrace}"
    end
  when :down
    to   = (to == '.' ? 0 : to).to_i
    return @logger.error "Can't migrate down to a higher version (#{from} to #{to})" if to > from
    return @logger.info  "Database is up to date" if to == from

    @logger.info "Drowngrading database from version #{from} to #{to}"
    begin
      @migrations[to+1..from].reverse_each do |migration|
        Object.const_get(migration).apply(:down)
      end
      @current_version.update_attributes(value: to.to_s)
      @logger.info "OK"
    rescue => e
      @logger.error "#{e.message}\n#{e.backtrace}"
    end
  end
end