require 'active_record/connection_adapters/abstract_adapter'
require 'active_record/connection_adapters/statement_pool'
require 'active_record/connection_adapters/postgresql/oid'
require 'active_record/connection_adapters/postgresql/cast'
require 'active_record/connection_adapters/postgresql/array_parser'
require 'active_record/connection_adapters/postgresql/quoting'
require 'active_record/connection_adapters/postgresql/schema_statements'
require 'active_record/connection_adapters/postgresql/database_statements'
require 'active_record/connection_adapters/postgresql/referential_integrity'
require 'active_record/connection_adapters/postgresql/column'
require 'arel/visitors/bind_visitor'
# Make sure we're using pg high enough for PGResult#values
gem 'pg', '~> 0.11'
require 'pg'
require 'ipaddr'
module ActiveRecord
module ConnectionHandling # :nodoc:
VALID_CONN_PARAMS = [:host, :hostaddr, :port, :dbname, :user, :password, :connect_timeout,
:client_encoding, :options, :application_name, :fallback_application_name,
:keepalives, :keepalives_idle, :keepalives_interval, :keepalives_count,
:tty, :sslmode, :requiressl, :sslcompression, :sslcert, :sslkey,
:sslrootcert, :sslcrl, :requirepeer, :krbsrvname, :gsslib, :service]
# Establishes a connection to the database that's used by all Active Record objects
def postgresql_connection(config)
conn_params = config.symbolize_keys
conn_params.delete_if { |_, v| v.nil? }
# Map ActiveRecords param names to PGs.
conn_params[:user] = conn_params.delete(:username) if conn_params[:username]
conn_params[:dbname] = conn_params.delete(:database) if conn_params[:database]
# Forward only valid config params to PGconn.connect.
conn_params.keep_if { |k, _| VALID_CONN_PARAMS.include?(k) }
# The postgres drivers don't allow the creation of an unconnected PGconn object,
# so just pass a nil connection object for the time being.
ConnectionAdapters::PostgreSQLAdapter.new(nil, logger, conn_params, config)
end
end
module ConnectionAdapters
# The PostgreSQL adapter works with the native C (https://bitbucket.org/ged/ruby-pg) driver.
#
# Options:
#
# * :host - Defaults to a Unix-domain socket in /tmp. On machines without Unix-domain sockets,
# the default is to connect to localhost.
# * :port - Defaults to 5432.
# * :username - Defaults to be the same as the operating system name of the user running the application.
# * :password - Password to be used if the server demands password authentication.
# * :database - Defaults to be the same as the user name.
# * :schema_search_path - An optional schema search path for the connection given
# as a string of comma-separated schema names. This is backward-compatible with the :schema_order option.
# * :encoding - An optional client encoding that is used in a SET client_encoding TO
# call on the connection.
# * :min_messages - An optional client min messages that is used in a
# SET client_min_messages TO call on the connection.
# * :variables - An optional hash of additional parameters that
# will be used in SET SESSION key = val calls on the connection.
# * :insert_returning - An optional boolean to control the use or RETURNING for INSERT statements
# defaults to true.
#
# Any further options are used as connection parameters to libpq. See
# http://www.postgresql.org/docs/9.1/static/libpq-connect.html for the
# list of parameters.
#
# In addition, default connection parameters of libpq can be set per environment variables.
# See http://www.postgresql.org/docs/9.1/static/libpq-envars.html .
class PostgreSQLAdapter < AbstractAdapter
class ColumnDefinition < ActiveRecord::ConnectionAdapters::ColumnDefinition
attr_accessor :array
end
module ColumnMethods
def xml(*args)
options = args.extract_options!
column(args[0], 'xml', options)
end
def tsvector(*args)
options = args.extract_options!
column(args[0], 'tsvector', options)
end
def int4range(name, options = {})
column(name, 'int4range', options)
end
def int8range(name, options = {})
column(name, 'int8range', options)
end
def tsrange(name, options = {})
column(name, 'tsrange', options)
end
def tstzrange(name, options = {})
column(name, 'tstzrange', options)
end
def numrange(name, options = {})
column(name, 'numrange', options)
end
def daterange(name, options = {})
column(name, 'daterange', options)
end
def hstore(name, options = {})
column(name, 'hstore', options)
end
def ltree(name, options = {})
column(name, 'ltree', options)
end
def inet(name, options = {})
column(name, 'inet', options)
end
def cidr(name, options = {})
column(name, 'cidr', options)
end
def macaddr(name, options = {})
column(name, 'macaddr', options)
end
def uuid(name, options = {})
column(name, 'uuid', options)
end
def json(name, options = {})
column(name, 'json', options)
end
def citext(name, options = {})
column(name, 'citext', options)
end
end
class TableDefinition < ActiveRecord::ConnectionAdapters::TableDefinition
include ColumnMethods
# Defines the primary key field.
# Use of the native PostgreSQL UUID type is supported, and can be used
# by defining your tables as such:
#
# create_table :stuffs, id: :uuid do |t|
# t.string :content
# t.timestamps
# end
#
# By default, this will use the +uuid_generate_v4()+ function from the
# +uuid-ossp+ extension, which MUST be enabled on your database. To enable
# the +uuid-ossp+ extension, you can use the +enable_extension+ method in your
# migrations. To use a UUID primary key without +uuid-ossp+ enabled, you can
# set the +:default+ option to +nil+:
#
# create_table :stuffs, id: false do |t|
# t.primary_key :id, :uuid, default: nil
# t.uuid :foo_id
# t.timestamps
# end
#
# You may also pass a different UUID generation function from +uuid-ossp+
# or another library.
#
# Note that setting the UUID primary key default value to +nil+ will
# require you to assure that you always provide a UUID value before saving
# a record (as primary keys cannot be +nil+). This might be done via the
# +SecureRandom.uuid+ method and a +before_save+ callback, for instance.
def primary_key(name, type = :primary_key, options = {})
return super unless type == :uuid
options[:default] = options.fetch(:default, 'uuid_generate_v4()')
options[:primary_key] = true
column name, type, options
end
def citext(name, options = {})
column(name, 'citext', options)
end
def column(name, type = nil, options = {})
super
column = self[name]
column.array = options[:array]
self
end
private
def create_column_definition(name, type)
ColumnDefinition.new name, type
end
end
class Table < ActiveRecord::ConnectionAdapters::Table
include ColumnMethods
end
ADAPTER_NAME = 'PostgreSQL'
NATIVE_DATABASE_TYPES = {
primary_key: "serial primary key",
string: { name: "character varying", limit: 255 },
text: { name: "text" },
integer: { name: "integer" },
float: { name: "float" },
decimal: { name: "decimal" },
datetime: { name: "timestamp" },
timestamp: { name: "timestamp" },
time: { name: "time" },
date: { name: "date" },
daterange: { name: "daterange" },
numrange: { name: "numrange" },
tsrange: { name: "tsrange" },
tstzrange: { name: "tstzrange" },
int4range: { name: "int4range" },
int8range: { name: "int8range" },
binary: { name: "bytea" },
boolean: { name: "boolean" },
xml: { name: "xml" },
tsvector: { name: "tsvector" },
hstore: { name: "hstore" },
inet: { name: "inet" },
cidr: { name: "cidr" },
macaddr: { name: "macaddr" },
uuid: { name: "uuid" },
json: { name: "json" },
ltree: { name: "ltree" },
citext: { name: "citext" }
}
include Quoting
include ReferentialIntegrity
include SchemaStatements
include DatabaseStatements
include Savepoints
# Returns 'PostgreSQL' as adapter name for identification purposes.
def adapter_name
ADAPTER_NAME
end
# Adds `:array` option to the default set provided by the
# AbstractAdapter
def prepare_column_options(column, types)
spec = super
spec[:array] = 'true' if column.respond_to?(:array) && column.array
spec[:default] = "\"#{column.default_function}\"" if column.default_function
spec
end
# Adds `:array` as a valid migration key
def migration_keys
super + [:array]
end
# Returns +true+, since this connection adapter supports prepared statement
# caching.
def supports_statement_cache?
true
end
def supports_index_sort_order?
true
end
def supports_partial_index?
true
end
def supports_transaction_isolation?
true
end
def index_algorithms
{ concurrently: 'CONCURRENTLY' }
end
class StatementPool < ConnectionAdapters::StatementPool
def initialize(connection, max)
super
@counter = 0
@cache = Hash.new { |h,pid| h[pid] = {} }
end
def each(&block); cache.each(&block); end
def key?(key); cache.key?(key); end
def [](key); cache[key]; end
def length; cache.length; end
def next_key
"a#{@counter + 1}"
end
def []=(sql, key)
while @max <= cache.size
dealloc(cache.shift.last)
end
@counter += 1
cache[sql] = key
end
def clear
cache.each_value do |stmt_key|
dealloc stmt_key
end
cache.clear
end
def delete(sql_key)
dealloc cache[sql_key]
cache.delete sql_key
end
private
def cache
@cache[Process.pid]
end
def dealloc(key)
@connection.query "DEALLOCATE #{key}" if connection_active?
end
def connection_active?
@connection.status == PGconn::CONNECTION_OK
rescue PGError
false
end
end
class BindSubstitution < Arel::Visitors::PostgreSQL # :nodoc:
include Arel::Visitors::BindVisitor
end
# Initializes and connects a PostgreSQL adapter.
def initialize(connection, logger, connection_parameters, config)
super(connection, logger)
if self.class.type_cast_config_to_boolean(config.fetch(:prepared_statements) { true })
@prepared_statements = true
@visitor = Arel::Visitors::PostgreSQL.new self
else
@visitor = unprepared_visitor
end
@connection_parameters, @config = connection_parameters, config
# @local_tz is initialized as nil to avoid warnings when connect tries to use it
@local_tz = nil
@table_alias_length = nil
connect
@statements = StatementPool.new @connection,
self.class.type_cast_config_to_integer(config.fetch(:statement_limit) { 1000 })
if postgresql_version < 80200
raise "Your version of PostgreSQL (#{postgresql_version}) is too old, please upgrade!"
end
@type_map = OID::TypeMap.new
initialize_type_map(type_map)
@local_tz = execute('SHOW TIME ZONE', 'SCHEMA').first["TimeZone"]
@use_insert_returning = @config.key?(:insert_returning) ? self.class.type_cast_config_to_boolean(@config[:insert_returning]) : true
end
# Clears the prepared statements cache.
def clear_cache!
@statements.clear
end
# Is this connection alive and ready for queries?
def active?
@connection.query 'SELECT 1'
true
rescue PGError
false
end
# Close then reopen the connection.
def reconnect!
super
@connection.reset
configure_connection
end
def reset!
clear_cache!
reset_transaction
unless @connection.transaction_status == ::PG::PQTRANS_IDLE
@connection.query 'ROLLBACK'
end
@connection.query 'DISCARD ALL'
configure_connection
end
# Disconnects from the database if already connected. Otherwise, this
# method does nothing.
def disconnect!
super
@connection.close rescue nil
end
def native_database_types #:nodoc:
NATIVE_DATABASE_TYPES
end
# Returns true, since this connection adapter supports migrations.
def supports_migrations?
true
end
# Does PostgreSQL support finding primary key on non-Active Record tables?
def supports_primary_key? #:nodoc:
true
end
# Enable standard-conforming strings if available.
def set_standard_conforming_strings
old, self.client_min_messages = client_min_messages, 'panic'
execute('SET standard_conforming_strings = on', 'SCHEMA') rescue nil
ensure
self.client_min_messages = old
end
def supports_insert_with_returning?
true
end
def supports_ddl_transactions?
true
end
def supports_explain?
true
end
# Returns true if pg > 9.1
def supports_extensions?
postgresql_version >= 90100
end
# Range datatypes weren't introduced until PostgreSQL 9.2
def supports_ranges?
postgresql_version >= 90200
end
def enable_extension(name)
exec_query("CREATE EXTENSION IF NOT EXISTS \"#{name}\"").tap {
reload_type_map
}
end
def disable_extension(name)
exec_query("DROP EXTENSION IF EXISTS \"#{name}\" CASCADE").tap {
reload_type_map
}
end
def extension_enabled?(name)
if supports_extensions?
res = exec_query "SELECT EXISTS(SELECT * FROM pg_available_extensions WHERE name = '#{name}' AND installed_version IS NOT NULL) as enabled",
'SCHEMA'
res.column_types['enabled'].type_cast res.rows.first.first
end
end
def extensions
if supports_extensions?
res = exec_query "SELECT extname from pg_extension", "SCHEMA"
res.rows.map { |r| res.column_types['extname'].type_cast r.first }
else
super
end
end
# Returns the configured supported identifier length supported by PostgreSQL
def table_alias_length
@table_alias_length ||= query('SHOW max_identifier_length', 'SCHEMA')[0][0].to_i
end
# Set the authorized user for this session
def session_auth=(user)
clear_cache!
exec_query "SET SESSION AUTHORIZATION #{user}"
end
module Utils
extend self
# Returns an array of [schema_name, table_name] extracted from +name+.
# +schema_name+ is nil if not specified in +name+.
# +schema_name+ and +table_name+ exclude surrounding quotes (regardless of whether provided in +name+)
# +name+ supports the range of schema/table references understood by PostgreSQL, for example:
#
# * table_name
# * "table.name"
# * schema_name.table_name
# * schema_name."table.name"
# * "schema.name"."table name"
def extract_schema_and_table(name)
table, schema = name.scan(/[^".\s]+|"[^"]*"/)[0..1].collect{|m| m.gsub(/(^"|"$)/,'') }.reverse
[schema, table]
end
end
def use_insert_returning?
@use_insert_returning
end
def valid_type?(type)
!native_database_types[type].nil?
end
def update_table_definition(table_name, base) #:nodoc:
Table.new(table_name, base)
end
protected
# Returns the version of the connected PostgreSQL server.
def postgresql_version
@connection.server_version
end
# See http://www.postgresql.org/docs/9.1/static/errcodes-appendix.html
FOREIGN_KEY_VIOLATION = "23503"
UNIQUE_VIOLATION = "23505"
def translate_exception(exception, message)
return exception unless exception.respond_to?(:result)
case exception.result.try(:error_field, PGresult::PG_DIAG_SQLSTATE)
when UNIQUE_VIOLATION
RecordNotUnique.new(message, exception)
when FOREIGN_KEY_VIOLATION
InvalidForeignKey.new(message, exception)
else
super
end
end
private
def type_map
@type_map
end
def reload_type_map
type_map.clear
initialize_type_map(type_map)
end
def add_oid(row, records_by_oid, type_map)
return type_map if type_map.key? row['type_elem'].to_i
if OID.registered_type? row['typname']
# this composite type is explicitly registered
vector = OID::NAMES[row['typname']]
else
# use the default for composite types
unless type_map.key? row['typelem'].to_i
add_oid records_by_oid[row['typelem']], records_by_oid, type_map
end
vector = OID::Vector.new row['typdelim'], type_map[row['typelem'].to_i]
end
type_map[row['oid'].to_i] = vector
type_map
end
def initialize_type_map(type_map)
if supports_ranges?
result = execute(<<-SQL, 'SCHEMA')
SELECT t.oid, t.typname, t.typelem, t.typdelim, t.typinput, r.rngsubtype, t.typtype, t.typbasetype
FROM pg_type as t
LEFT JOIN pg_range as r ON oid = rngtypid
SQL
else
result = execute(<<-SQL, 'SCHEMA')
SELECT t.oid, t.typname, t.typelem, t.typdelim, t.typinput
FROM pg_type as t
SQL
end
ranges, nodes = result.partition { |row| row['typtype'] == 'r' }
enums, nodes = nodes.partition { |row| row['typtype'] == 'e' }
domains, nodes = nodes.partition { |row| row['typtype'] == 'd' }
arrays, nodes = nodes.partition { |row| row['typinput'] == 'array_in' }
leaves, nodes = nodes.partition { |row| row['typelem'] == '0' }
# populate the enum types
enums.each do |row|
type_map[row['oid'].to_i] = OID::Enum.new
end
# populate the base types
leaves.find_all { |row| OID.registered_type? row['typname'] }.each do |row|
type_map[row['oid'].to_i] = OID::NAMES[row['typname']]
end
records_by_oid = result.group_by { |row| row['oid'] }
# populate composite types
nodes.each do |row|
add_oid row, records_by_oid, type_map
end
# populate array types
arrays.find_all { |row| type_map.key? row['typelem'].to_i }.each do |row|
array = OID::Array.new type_map[row['typelem'].to_i]
type_map[row['oid'].to_i] = array
end
# populate range types
ranges.find_all { |row| type_map.key? row['rngsubtype'].to_i }.each do |row|
subtype = type_map[row['rngsubtype'].to_i]
range = OID::Range.new subtype
type_map[row['oid'].to_i] = range
end
# populate domain types
domains.each do |row|
if base_type = type_map[row["typbasetype"].to_i]
type_map[row['oid'].to_i] = base_type
else
warn "unknown base type (OID: #{row["typbasetype"].to_i}) for domain #{row["typname"]}."
end
end
end
FEATURE_NOT_SUPPORTED = "0A000" #:nodoc:
def exec_no_cache(sql, name, binds)
log(sql, name, binds) { @connection.async_exec(sql) }
end
def exec_cache(sql, name, binds)
stmt_key = prepare_statement(sql)
type_casted_binds = binds.map { |col, val|
[col, type_cast(val, col)]
}
log(sql, name, type_casted_binds, stmt_key) do
@connection.send_query_prepared(stmt_key, type_casted_binds.map { |_, val| val })
@connection.block
@connection.get_last_result
end
rescue ActiveRecord::StatementInvalid => e
pgerror = e.original_exception
# Get the PG code for the failure. Annoyingly, the code for
# prepared statements whose return value may have changed is
# FEATURE_NOT_SUPPORTED. Check here for more details:
# http://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/utils/cache/plancache.c#l573
begin
code = pgerror.result.result_error_field(PGresult::PG_DIAG_SQLSTATE)
rescue
raise e
end
if FEATURE_NOT_SUPPORTED == code
@statements.delete sql_key(sql)
retry
else
raise e
end
end
# Returns the statement identifier for the client side cache
# of statements
def sql_key(sql)
"#{schema_search_path}-#{sql}"
end
# Prepare the statement if it hasn't been prepared, return
# the statement key.
def prepare_statement(sql)
sql_key = sql_key(sql)
unless @statements.key? sql_key
nextkey = @statements.next_key
begin
@connection.prepare nextkey, sql
rescue => e
raise translate_exception_class(e, sql)
end
# Clear the queue
@connection.get_last_result
@statements[sql_key] = nextkey
end
@statements[sql_key]
end
# The internal PostgreSQL identifier of the money data type.
MONEY_COLUMN_TYPE_OID = 790 #:nodoc:
# The internal PostgreSQL identifier of the BYTEA data type.
BYTEA_COLUMN_TYPE_OID = 17 #:nodoc:
# Connects to a PostgreSQL server and sets up the adapter depending on the
# connected server's characteristics.
def connect
@connection = PGconn.connect(@connection_parameters)
# Money type has a fixed precision of 10 in PostgreSQL 8.2 and below, and as of
# PostgreSQL 8.3 it has a fixed precision of 19. PostgreSQLColumn.extract_precision
# should know about this but can't detect it there, so deal with it here.
PostgreSQLColumn.money_precision = (postgresql_version >= 80300) ? 19 : 10
configure_connection
rescue ::PG::Error => error
if error.message.include?("does not exist")
raise ActiveRecord::NoDatabaseError.new(error.message)
else
raise error
end
end
# Configures the encoding, verbosity, schema search path, and time zone of the connection.
# This is called by #connect and should not be called manually.
def configure_connection
if @config[:encoding]
@connection.set_client_encoding(@config[:encoding])
end
self.client_min_messages = @config[:min_messages] || 'warning'
self.schema_search_path = @config[:schema_search_path] || @config[:schema_order]
# Use standard-conforming strings if available so we don't have to do the E'...' dance.
set_standard_conforming_strings
# If using Active Record's time zone support configure the connection to return
# TIMESTAMP WITH ZONE types in UTC.
# (SET TIME ZONE does not use an equals sign like other SET variables)
if ActiveRecord::Base.default_timezone == :utc
execute("SET time zone 'UTC'", 'SCHEMA')
elsif @local_tz
execute("SET time zone '#{@local_tz}'", 'SCHEMA')
end
# SET statements from :variables config hash
# http://www.postgresql.org/docs/8.3/static/sql-set.html
variables = @config[:variables] || {}
variables.map do |k, v|
if v == ':default' || v == :default
# Sets the value to the global or compile default
execute("SET SESSION #{k.to_s} TO DEFAULT", 'SCHEMA')
elsif !v.nil?
execute("SET SESSION #{k.to_s} TO #{quote(v)}", 'SCHEMA')
end
end
end
# Returns the current ID of a table's sequence.
def last_insert_id(sequence_name) #:nodoc:
Integer(last_insert_id_value(sequence_name))
end
def last_insert_id_value(sequence_name)
last_insert_id_result(sequence_name).rows.first.first
end
def last_insert_id_result(sequence_name) #:nodoc:
exec_query("SELECT currval('#{sequence_name}')", 'SQL')
end
# Executes a SELECT query and returns the results, performing any data type
# conversions that are required to be performed here instead of in PostgreSQLColumn.
def select(sql, name = nil, binds = [])
exec_query(sql, name, binds)
end
# Returns the list of a table's column names, data types, and default values.
#
# The underlying query is roughly:
# SELECT column.name, column.type, default.value
# FROM column LEFT JOIN default
# ON column.table_id = default.table_id
# AND column.num = default.column_num
# WHERE column.table_id = get_table_id('table_name')
# AND column.num > 0
# AND NOT column.is_dropped
# ORDER BY column.num
#
# If the table name is not prefixed with a schema, the database will
# take the first match from the schema search path.
#
# Query implementation notes:
# - format_type includes the column size constraint, e.g. varchar(50)
# - ::regclass is a function that gives the id for a table name
def column_definitions(table_name) #:nodoc:
exec_query(<<-end_sql, 'SCHEMA').rows
SELECT a.attname, format_type(a.atttypid, a.atttypmod),
pg_get_expr(d.adbin, d.adrelid), a.attnotnull, a.atttypid, a.atttypmod
FROM pg_attribute a LEFT JOIN pg_attrdef d
ON a.attrelid = d.adrelid AND a.attnum = d.adnum
WHERE a.attrelid = '#{quote_table_name(table_name)}'::regclass
AND a.attnum > 0 AND NOT a.attisdropped
ORDER BY a.attnum
end_sql
end
def extract_pg_identifier_from_name(name)
match_data = name.start_with?('"') ? name.match(/\"([^\"]+)\"/) : name.match(/([^\.]+)/)
if match_data
rest = name[match_data[0].length, name.length]
rest = rest[1, rest.length] if rest.start_with? "."
[match_data[1], (rest.length > 0 ? rest : nil)]
end
end
def extract_table_ref_from_insert_sql(sql)
sql[/into\s+([^\(]*).*values\s*\(/im]
$1.strip if $1
end
def create_table_definition(name, temporary, options, as = nil)
TableDefinition.new native_database_types, name, temporary, options, as
end
end
end
end