Class: PgSync::DataSource

Inherits:
Object
  • Object
show all
Defined in:
lib/pgsync/data_source.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(source) ⇒ DataSource 



5
6
7
 
# File 'lib/pgsync/data_source.rb', line 5

def initialize(source)
  @url = resolve_url(source)
end

Instance Attribute Details

#url ⇒ Object (readonly)

Returns the value of attribute url.



3
4
5
 
# File 'lib/pgsync/data_source.rb', line 3

def url
  @url
end

Instance Method Details

#close ⇒ Object 



42
43
44
45
46
47
 
# File 'lib/pgsync/data_source.rb', line 42

def close
  if @conn
    conn.close
    @conn = nil
  end
end

#columns(table) ⇒ Object 



55
56
57
58
 
# File 'lib/pgsync/data_source.rb', line 55

def columns(table)
  query = "SELECT column_name FROM information_schema.columns WHERE table_schema = $1 AND table_name = $2"
  execute(query, table.split(".", 2)).map { |row| row["column_name"] }
end

#conn ⇒ Object

borrowed from ActiveRecord::ConnectionAdapters::ConnectionSpecification::ConnectionUrlResolver



103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
 
# File 'lib/pgsync/data_source.rb', line 103

def conn
  @conn ||= begin
    begin
      uri_parser = URI::Parser.new
      config = {
          host: uri.host,
          port: uri.port,
          dbname: uri.path.sub(/\A\//, ""),
          user: uri.user,
          password: uri.password,
          connect_timeout: 3
      }.reject { |_, value| value.to_s.empty? }
      config.map { |key, value| config[key] = uri_parser.unescape(value) if value.is_a?(String) }
      conn = PG::Connection.new(config)
    rescue PG::ConnectionBad => e
      log
      raise PgSync::Error, e.message
    end
  end
end

#dump_command(tables) ⇒ Object 



124
125
126
127
 
# File 'lib/pgsync/data_source.rb', line 124

def dump_command(tables)
  tables = tables.keys.map { |t| "-t #{Shellwords.escape(quote_ident_full(t))}" }.join(" ")
  dump_command = "pg_dump -Fc --verbose --schema-only --no-owner --no-acl #{tables} #{to_url}"
end

#exists? ⇒ Boolean 



9
10
11
 
# File 'lib/pgsync/data_source.rb', line 9

def exists?
  @url && @url.size > 0
end

#fully_resolve_tables(tables) ⇒ Object 



135
136
137
138
139
140
141
142
143
 
# File 'lib/pgsync/data_source.rb', line 135

def fully_resolve_tables(tables)
  no_schema_tables = {}
  search_path_index = Hash[search_path.map.with_index.to_a]
  self.tables.group_by { |t| t.split(".", 2)[-1] }.each do |group, t2|
    no_schema_tables[group] = t2.sort_by { |t| [search_path_index[t.split(".", 2)[0]] || 1000000, t] }[0]
  end

  Hash[tables.map { |k, v| [no_schema_tables[k] || k, v] }]
end

#last_value(seq) ⇒ Object 



72
73
74
 
# File 'lib/pgsync/data_source.rb', line 72

def last_value(seq)
  execute("select last_value from #{seq}")[0]["last_value"]
end

#local? ⇒ Boolean 



13
14
15
 
# File 'lib/pgsync/data_source.rb', line 13

def local?
  %w(localhost 127.0.0.1).include?(uri.host)
end

#max_id(table, primary_key, sql_clause = nil) ⇒ Object 



64
65
66
 
# File 'lib/pgsync/data_source.rb', line 64

def max_id(table, primary_key, sql_clause = nil)
  execute("SELECT MAX(#{quote_ident(primary_key)}) FROM #{quote_ident_full(table)}#{sql_clause}")[0]["max"].to_i
end

#min_id(table, primary_key, sql_clause = nil) ⇒ Object 



68
69
70
 
# File 'lib/pgsync/data_source.rb', line 68

def min_id(table, primary_key, sql_clause = nil)
  execute("SELECT MIN(#{quote_ident(primary_key)}) FROM #{quote_ident_full(table)}#{sql_clause}")[0]["min"].to_i
end

#primary_key(table) ⇒ Object

stackoverflow.com/a/20537829



81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
 
# File 'lib/pgsync/data_source.rb', line 81

def primary_key(table)
  query = "    SELECT\n      pg_attribute.attname,\n      format_type(pg_attribute.atttypid, pg_attribute.atttypmod)\n    FROM\n      pg_index, pg_class, pg_attribute, pg_namespace\n    WHERE\n      pg_class.oid = $2::regclass AND\n      indrelid = pg_class.oid AND\n      nspname = $1 AND\n      pg_class.relnamespace = pg_namespace.oid AND\n      pg_attribute.attrelid = pg_class.oid AND\n      pg_attribute.attnum = any(pg_index.indkey) AND\n      indisprimary\n  SQL\n  row = execute(query, [table.split(\".\", 2)[0], quote_ident_full(table)])[0]\n  row && row[\"attname\"]\nend\n"

#restore_command ⇒ Object 



129
130
131
132
133
 
# File 'lib/pgsync/data_source.rb', line 129

def restore_command
  psql_version = Gem::Version.new(`psql --version`.lines[0].chomp.split(" ")[-1].sub(/beta\d/, ""))
  if_exists = psql_version >= Gem::Version.new("9.4.0")
  restore_command = "pg_restore --verbose --no-owner --no-acl --clean #{if_exists ? "--if-exists" : nil} -d #{to_url}"
end

#schema ⇒ Object 



28
29
30
 
# File 'lib/pgsync/data_source.rb', line 28

def schema
  @schema ||= CGI.parse(uri.query.to_s)["schema"][0]
end

#search_path ⇒ Object 



145
146
147
 
# File 'lib/pgsync/data_source.rb', line 145

def search_path
  execute("SELECT current_schemas(true)")[0]["current_schemas"][1..-2].split(",")
end

#sequences(table, columns) ⇒ Object 



60
61
62
 
# File 'lib/pgsync/data_source.rb', line 60

def sequences(table, columns)
  execute("SELECT #{columns.map { |f| "pg_get_serial_sequence(#{escape("#{quote_ident_full(table)}")}, #{escape(f)}) AS #{f}" }.join(", ")}")[0].values.compact
end

#table_exists?(table) ⇒ Boolean 



37
38
39
40
 
# File 'lib/pgsync/data_source.rb', line 37

def table_exists?(table)
  query = "SELECT 1 FROM information_schema.tables WHERE table_schema = $1 AND table_name = $2"
  execute(query, table.split(".", 2)).size > 0
end

#tables ⇒ Object 



32
33
34
35
 
# File 'lib/pgsync/data_source.rb', line 32

def tables
  query = "SELECT schemaname, tablename FROM pg_catalog.pg_tables WHERE schemaname NOT IN ('information_schema', 'pg_catalog') ORDER BY 1, 2"
  execute(query).map { |row| "#{row["schemaname"]}.#{row["tablename"]}" }
end

#to_url ⇒ Object 



49
50
51
52
53
 
# File 'lib/pgsync/data_source.rb', line 49

def to_url
  uri = self.uri.dup
  uri.query = nil
  uri.to_s
end

#truncate(table) ⇒ Object 



76
77
78
 
# File 'lib/pgsync/data_source.rb', line 76

def truncate(table)
  execute("TRUNCATE #{quote_ident_full(table)} CASCADE")
end

#uri ⇒ Object 



17
18
19
20
21
22
23
24
25
26
 
# File 'lib/pgsync/data_source.rb', line 17

def uri
  @uri ||= begin
    uri = URI.parse(@url)
    uri.scheme ||= "postgres"
    uri.host ||= "localhost"
    uri.port ||= 5432
    uri.path = "/#{uri.path}" if uri.path && uri.path[0] != "/"
    uri
  end
end