activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
# frozen_string_literal: true
gem "pg", "~> 1.1"
require "pg"
require "active_support/core_ext/object/try"
require "active_record/connection_adapters/abstract_adapter"
require "active_record/connection_adapters/statement_pool"
require "active_record/connection_adapters/postgresql/column"
require "active_record/connection_adapters/postgresql/database_statements"
require "active_record/connection_adapters/postgresql/explain_pretty_printer"
require "active_record/connection_adapters/postgresql/oid"
require "active_record/connection_adapters/postgresql/quoting"
require "active_record/connection_adapters/postgresql/referential_integrity"
require "active_record/connection_adapters/postgresql/schema_creation"
require "active_record/connection_adapters/postgresql/schema_definitions"
require "active_record/connection_adapters/postgresql/schema_dumper"
require "active_record/connection_adapters/postgresql/schema_statements"
require "active_record/connection_adapters/postgresql/type_metadata"
require "active_record/connection_adapters/postgresql/utils"
module ActiveRecord
module ConnectionAdapters
# = Active Record PostgreSQL Adapter
#
# The PostgreSQL adapter works with the native C (https://github.com/ged/ruby-pg) driver.
#
# Options:
#
# * <tt>:host</tt> - Defaults to a Unix-domain socket in /tmp. On machines without Unix-domain sockets,
# the default is to connect to localhost.
# * <tt>:port</tt> - Defaults to 5432.
# * <tt>:username</tt> - Defaults to be the same as the operating system name of the user running the application.
# * <tt>:password</tt> - Password to be used if the server demands password authentication.
# * <tt>:database</tt> - Defaults to be the same as the username.
# * <tt>:schema_search_path</tt> - An optional schema search path for the connection given
# as a string of comma-separated schema names. This is backward-compatible with the <tt>:schema_order</tt> option.
# * <tt>:encoding</tt> - An optional client encoding that is used in a <tt>SET client_encoding TO
# <encoding></tt> call on the connection.
# * <tt>:min_messages</tt> - An optional client min messages that is used in a
# <tt>SET client_min_messages TO <min_messages></tt> call on the connection.
# * <tt>:variables</tt> - An optional hash of additional parameters that
# will be used in <tt>SET SESSION key = val</tt> calls on the connection.
# * <tt>:insert_returning</tt> - An optional boolean to control the use of <tt>RETURNING</tt> for <tt>INSERT</tt> statements
# defaults to true.
#
# Any further options are used as connection parameters to libpq. See
# https://www.postgresql.org/docs/current/static/libpq-connect.html for the
# list of parameters.
#
# In addition, default connection parameters of libpq can be set per environment variables.
# See https://www.postgresql.org/docs/current/static/libpq-envars.html .
class PostgreSQLAdapter < AbstractAdapter
ADAPTER_NAME = "PostgreSQL"
class << self
def new_client(conn_params)
PG.connect(**conn_params)
rescue ::PG::Error => error
if conn_params && conn_params[:dbname] == "postgres"
raise ActiveRecord::ConnectionNotEstablished, error.message
elsif conn_params && conn_params[:dbname] && error.message.include?(conn_params[:dbname])
raise ActiveRecord::NoDatabaseError.db_error(conn_params[:dbname])
elsif conn_params && conn_params[:user] && error.message.include?(conn_params[:user])
raise ActiveRecord::DatabaseConnectionError.username_error(conn_params[:user])
elsif conn_params && conn_params[:host] && error.message.include?(conn_params[:host])
raise ActiveRecord::DatabaseConnectionError.hostname_error(conn_params[:host])
else
raise ActiveRecord::ConnectionNotEstablished, error.message
end
end
def dbconsole(config, options = {})
pg_config = config.configuration_hash
ENV["PGUSER"] = pg_config[:username] if pg_config[:username]
ENV["PGHOST"] = pg_config[:host] if pg_config[:host]
ENV["PGPORT"] = pg_config[:port].to_s if pg_config[:port]
ENV["PGPASSWORD"] = pg_config[:password].to_s if pg_config[:password] && options[:include_password]
ENV["PGSSLMODE"] = pg_config[:sslmode].to_s if pg_config[:sslmode]
ENV["PGSSLCERT"] = pg_config[:sslcert].to_s if pg_config[:sslcert]
ENV["PGSSLKEY"] = pg_config[:sslkey].to_s if pg_config[:sslkey]
ENV["PGSSLROOTCERT"] = pg_config[:sslrootcert].to_s if pg_config[:sslrootcert]
if pg_config[:variables]
ENV["PGOPTIONS"] = pg_config[:variables].filter_map do |name, value|
"-c #{name}=#{value.to_s.gsub(/[ \\]/, '\\\\\0')}" unless value == ":default" || value == :default
end.join(" ")
end
find_cmd_and_exec("psql", config.database)
end
end
##
# :singleton-method:
# PostgreSQL allows the creation of "unlogged" tables, which do not record
# data in the PostgreSQL Write-Ahead Log. This can make the tables faster,
# but significantly increases the risk of data loss if the database
# crashes. As a result, this should not be used in production
# environments. If you would like all created tables to be unlogged in
# the test environment you can add the following to your test.rb file:
#
# ActiveSupport.on_load(:active_record_postgresqladapter) do
# self.create_unlogged_tables = true
# end
class_attribute :create_unlogged_tables, default: false
##
# :singleton-method:
# PostgreSQL supports multiple types for DateTimes. By default, if you use +datetime+
# in migrations, \Rails will translate this to a PostgreSQL "timestamp without time zone".
# Change this in an initializer to use another NATIVE_DATABASE_TYPES. For example, to
# store DateTimes as "timestamp with time zone":
#
# ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.datetime_type = :timestamptz
#
# Or if you are adding a custom type:
#
# ActiveRecord::ConnectionAdapters::PostgreSQLAdapter::NATIVE_DATABASE_TYPES[:my_custom_type] = { name: "my_custom_type_name" }
# ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.datetime_type = :my_custom_type
#
# If you're using +:ruby+ as your +config.active_record.schema_format+ and you change this
# setting, you should immediately run <tt>bin/rails db:migrate</tt> to update the types in your schema.rb.
class_attribute :datetime_type, default: :timestamp
NATIVE_DATABASE_TYPES = {
primary_key: "bigserial primary key",
string: { name: "character varying" },
text: { name: "text" },
integer: { name: "integer", limit: 4 },
bigint: { name: "bigint" },
float: { name: "float" },
decimal: { name: "decimal" },
datetime: {}, # set dynamically based on datetime_type
timestamp: { name: "timestamp" },
timestamptz: { name: "timestamptz" },
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" },
jsonb: { name: "jsonb" },
ltree: { name: "ltree" },
citext: { name: "citext" },
point: { name: "point" },
line: { name: "line" },
lseg: { name: "lseg" },
box: { name: "box" },
path: { name: "path" },
polygon: { name: "polygon" },
circle: { name: "circle" },
bit: { name: "bit" },
bit_varying: { name: "bit varying" },
money: { name: "money" },
interval: { name: "interval" },
oid: { name: "oid" },
enum: {} # special type https://www.postgresql.org/docs/current/datatype-enum.html
}
OID = PostgreSQL::OID # :nodoc:
include PostgreSQL::Quoting
include PostgreSQL::ReferentialIntegrity
include PostgreSQL::SchemaStatements
include PostgreSQL::DatabaseStatements
def supports_bulk_alter?
true
end
def supports_index_sort_order?
true
end
def supports_partitioned_indexes?
database_version >= 11_00_00 # >= 11.0
end
def supports_partial_index?
true
end
def supports_index_include?
database_version >= 11_00_00 # >= 11.0
end
def supports_expression_index?
true
end
def supports_transaction_isolation?
true
end
def supports_foreign_keys?
true
end
def supports_check_constraints?
true
end
def supports_exclusion_constraints?
true
end
def supports_unique_constraints?
true
end
def supports_validate_constraints?
true
end
def supports_deferrable_constraints?
true
end
def supports_views?
true
end
def supports_datetime_with_precision?
true
end
def supports_json?
true
end
def supports_comments?
true
end
def supports_savepoints?
true
end
def supports_restart_db_transaction?
database_version >= 12_00_00 # >= 12.0
end
def supports_insert_returning?
true
end
def supports_insert_on_conflict?
database_version >= 9_05_00 # >= 9.5
end
alias supports_insert_on_duplicate_skip? supports_insert_on_conflict?
alias supports_insert_on_duplicate_update? supports_insert_on_conflict?
alias supports_insert_conflict_target? supports_insert_on_conflict?
def supports_virtual_columns?
database_version >= 12_00_00 # >= 12.0
end
def supports_identity_columns? # :nodoc:
database_version >= 10_00_00 # >= 10.0
end
def supports_nulls_not_distinct?
database_version >= 15_00_00 # >= 15.0
end
def index_algorithms
{ concurrently: "CONCURRENTLY" }
end
class StatementPool < ConnectionAdapters::StatementPool # :nodoc:
def initialize(connection, max)
super(max)
@connection = connection
@counter = 0
end
def next_key
"a#{@counter += 1}"
end
private
def dealloc(key)
# This is ugly, but safe: the statement pool is only
# accessed while holding the connection's lock. (And we
# don't need the complication of with_raw_connection because
# a reconnect would invalidate the entire statement pool.)
if conn = @connection.instance_variable_get(:@raw_connection)
conn.query "DEALLOCATE #{key}" if conn.status == PG::CONNECTION_OK
end
rescue PG::Error
end
end
# Initializes and connects a PostgreSQL adapter.
def initialize(...)
super
conn_params = @config.compact
# 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 PG::Connection.connect.
valid_conn_param_keys = PG::Connection.conndefaults_hash.keys + [:requiressl]
conn_params.slice!(*valid_conn_param_keys)
@connection_parameters = conn_params
@max_identifier_length = nil
@type_map = nil
@raw_connection = nil
@notice_receiver_sql_warnings = []
@use_insert_returning = @config.key?(:insert_returning) ? self.class.type_cast_config_to_boolean(@config[:insert_returning]) : true
end
def connected?
!(@raw_connection.nil? || @raw_connection.finished?)
end
# Is this connection alive and ready for queries?
def active?
@lock.synchronize do
return false unless @raw_connection
@raw_connection.query ";"
end
true
rescue PG::Error
false
end
def reload_type_map # :nodoc:
@lock.synchronize do
if @type_map
type_map.clear
else
@type_map = Type::HashLookupTypeMap.new
end
initialize_type_map
end
end
def reset!
@lock.synchronize do
return connect! unless @raw_connection
unless @raw_connection.transaction_status == ::PG::PQTRANS_IDLE
@raw_connection.query "ROLLBACK"
end
@raw_connection.query "DISCARD ALL"
super
end
end
# Disconnects from the database if already connected. Otherwise, this
# method does nothing.
def disconnect!
@lock.synchronize do
super
@raw_connection&.close rescue nil
@raw_connection = nil
end
end
def discard! # :nodoc:
super
@raw_connection&.socket_io&.reopen(IO::NULL) rescue nil
@raw_connection = nil
end
def native_database_types # :nodoc:
self.class.native_database_types
end
def self.native_database_types # :nodoc:
@native_database_types ||= begin
types = NATIVE_DATABASE_TYPES.dup
types[:datetime] = types[datetime_type]
types
end
end
def set_standard_conforming_strings
internal_execute("SET standard_conforming_strings = on")
end
def supports_ddl_transactions?
true
end
def supports_advisory_locks?
true
end
def supports_explain?
true
end
def supports_extensions?
true
end
def supports_materialized_views?
true
end
def supports_foreign_tables?
true
end
def supports_pgcrypto_uuid?
database_version >= 9_04_00 # >= 9.4
end
def supports_optimizer_hints?
unless defined?(@has_pg_hint_plan)
@has_pg_hint_plan = extension_available?("pg_hint_plan")
end
@has_pg_hint_plan
end
def supports_common_table_expressions?
true
end
def supports_lazy_transactions?
true
end
def get_advisory_lock(lock_id) # :nodoc:
unless lock_id.is_a?(Integer) && lock_id.bit_length <= 63
raise(ArgumentError, "PostgreSQL requires advisory lock ids to be a signed 64 bit integer")
end
query_value("SELECT pg_try_advisory_lock(#{lock_id})")
end
def release_advisory_lock(lock_id) # :nodoc:
unless lock_id.is_a?(Integer) && lock_id.bit_length <= 63
raise(ArgumentError, "PostgreSQL requires advisory lock ids to be a signed 64 bit integer")
end
query_value("SELECT pg_advisory_unlock(#{lock_id})")
end
def enable_extension(name, **)
schema, name = name.to_s.split(".").values_at(-2, -1)
sql = +"CREATE EXTENSION IF NOT EXISTS \"#{name}\""
sql << " SCHEMA #{schema}" if schema
internal_exec_query(sql).tap { reload_type_map }
end
# Removes an extension from the database.
#
# [<tt>:force</tt>]
# Set to +:cascade+ to drop dependent objects as well.
# Defaults to false.
def disable_extension(name, force: false)
internal_exec_query("DROP EXTENSION IF EXISTS \"#{name}\"#{' CASCADE' if force == :cascade}").tap {
reload_type_map
}
end
def extension_available?(name)
query_value("SELECT true FROM pg_available_extensions WHERE name = #{quote(name)}", "SCHEMA")
end
def extension_enabled?(name)
query_value("SELECT installed_version IS NOT NULL FROM pg_available_extensions WHERE name = #{quote(name)}", "SCHEMA")
end
def extensions
internal_exec_query("SELECT extname FROM pg_extension", "SCHEMA", allow_retry: true, materialize_transactions: false).cast_values
end
# Returns a list of defined enum types, and their values.
def enum_types
query = <<~SQL
SELECT
type.typname AS name,
type.OID AS oid,
n.nspname AS schema,
string_agg(enum.enumlabel, ',' ORDER BY enum.enumsortorder) AS value
FROM pg_enum AS enum
JOIN pg_type AS type ON (type.oid = enum.enumtypid)
JOIN pg_namespace n ON type.typnamespace = n.oid
WHERE n.nspname = ANY (current_schemas(false))
GROUP BY type.OID, n.nspname, type.typname;
SQL
internal_exec_query(query, "SCHEMA", allow_retry: true, materialize_transactions: false).cast_values.each_with_object({}) do |row, memo|
name, schema = row[0], row[2]
schema = nil if schema == current_schema
full_name = [schema, name].compact.join(".")
memo[full_name] = row.last
end.to_a
end
# Given a name and an array of values, creates an enum type.
def create_enum(name, values, **options)
sql_values = values.map { |s| quote(s) }.join(", ")
scope = quoted_scope(name)
query = <<~SQL
DO $$
BEGIN
IF NOT EXISTS (
SELECT 1
FROM pg_type t
JOIN pg_namespace n ON t.typnamespace = n.oid
WHERE t.typname = #{scope[:name]}
AND n.nspname = #{scope[:schema]}
) THEN
CREATE TYPE #{quote_table_name(name)} AS ENUM (#{sql_values});
END IF;
END
$$;
SQL
internal_exec_query(query).tap { reload_type_map }
end
# Drops an enum type.
#
# If the <tt>if_exists: true</tt> option is provided, the enum is dropped
# only if it exists. Otherwise, if the enum doesn't exist, an error is
# raised.
#
# The +values+ parameter will be ignored if present. It can be helpful
# to provide this in a migration's +change+ method so it can be reverted.
# In that case, +values+ will be used by #create_enum.
def drop_enum(name, values = nil, **options)
query = <<~SQL
DROP TYPE#{' IF EXISTS' if options[:if_exists]} #{quote_table_name(name)};
SQL
internal_exec_query(query).tap { reload_type_map }
end
# Rename an existing enum type to something else.
def rename_enum(name, options = {})
to = options.fetch(:to) { raise ArgumentError, ":to is required" }
exec_query("ALTER TYPE #{quote_table_name(name)} RENAME TO #{to}").tap { reload_type_map }
end
# Add enum value to an existing enum type.
def add_enum_value(type_name, value, options = {})
before, after = options.values_at(:before, :after)
sql = +"ALTER TYPE #{quote_table_name(type_name)} ADD VALUE '#{value}'"
if before && after
raise ArgumentError, "Cannot have both :before and :after at the same time"
elsif before
sql << " BEFORE '#{before}'"
elsif after
sql << " AFTER '#{after}'"
end
execute(sql).tap { reload_type_map }
end
# Rename enum value on an existing enum type.
def rename_enum_value(type_name, options = {})
unless database_version >= 10_00_00 # >= 10.0
raise ArgumentError, "Renaming enum values is only supported in PostgreSQL 10 or later"
end
from = options.fetch(:from) { raise ArgumentError, ":from is required" }
to = options.fetch(:to) { raise ArgumentError, ":to is required" }
execute("ALTER TYPE #{quote_table_name(type_name)} RENAME VALUE '#{from}' TO '#{to}'").tap {
reload_type_map
}
end
# Returns the configured supported identifier length supported by PostgreSQL
def max_identifier_length
@max_identifier_length ||= query_value("SHOW max_identifier_length", "SCHEMA").to_i
end
# Set the authorized user for this session
def session_auth=(user)
clear_cache!
internal_execute("SET SESSION AUTHORIZATION #{user}", nil, materialize_transactions: true)
end
def use_insert_returning?
@use_insert_returning
end
# Returns the version of the connected PostgreSQL server.
def get_database_version # :nodoc:
with_raw_connection do |conn|
conn.server_version
end
end
alias :postgresql_version :database_version
def default_index_type?(index) # :nodoc:
index.using == :btree || super
end
def build_insert_sql(insert) # :nodoc:
sql = +"INSERT #{insert.into} #{insert.values_list}"
if insert.skip_duplicates?
sql << " ON CONFLICT #{insert.conflict_target} DO NOTHING"
elsif insert.update_duplicates?
sql << " ON CONFLICT #{insert.conflict_target} DO UPDATE SET "
if insert.raw_update_sql?
sql << insert.raw_update_sql
else
sql << insert.touch_model_timestamps_unless { |column| "#{insert.model.quoted_table_name}.#{column} IS NOT DISTINCT FROM excluded.#{column}" }
sql << insert.updatable_columns.map { |column| "#{column}=excluded.#{column}" }.join(",")
end
end
sql << " RETURNING #{insert.returning}" if insert.returning
sql
end
def check_version # :nodoc:
if database_version < 9_03_00 # < 9.3
raise "Your version of PostgreSQL (#{database_version}) is too old. Active Record supports PostgreSQL >= 9.3."
end
end
class << self
def initialize_type_map(m) # :nodoc:
m.register_type "int2", Type::Integer.new(limit: 2)
m.register_type "int4", Type::Integer.new(limit: 4)
m.register_type "int8", Type::Integer.new(limit: 8)
m.register_type "oid", OID::Oid.new
m.register_type "float4", Type::Float.new
m.alias_type "float8", "float4"
m.register_type "text", Type::Text.new
register_class_with_limit m, "varchar", Type::String
m.alias_type "char", "varchar"
m.alias_type "name", "varchar"
m.alias_type "bpchar", "varchar"
m.register_type "bool", Type::Boolean.new
register_class_with_limit m, "bit", OID::Bit
register_class_with_limit m, "varbit", OID::BitVarying
m.register_type "date", OID::Date.new
m.register_type "money", OID::Money.new
m.register_type "bytea", OID::Bytea.new
m.register_type "point", OID::Point.new
m.register_type "hstore", OID::Hstore.new
m.register_type "json", Type::Json.new
m.register_type "jsonb", OID::Jsonb.new
m.register_type "cidr", OID::Cidr.new
m.register_type "inet", OID::Inet.new
m.register_type "uuid", OID::Uuid.new
m.register_type "xml", OID::Xml.new
m.register_type "tsvector", OID::SpecializedString.new(:tsvector)
m.register_type "macaddr", OID::Macaddr.new
m.register_type "citext", OID::SpecializedString.new(:citext)
m.register_type "ltree", OID::SpecializedString.new(:ltree)
m.register_type "line", OID::SpecializedString.new(:line)
m.register_type "lseg", OID::SpecializedString.new(:lseg)
m.register_type "box", OID::SpecializedString.new(:box)
m.register_type "path", OID::SpecializedString.new(:path)
m.register_type "polygon", OID::SpecializedString.new(:polygon)
m.register_type "circle", OID::SpecializedString.new(:circle)
m.register_type "numeric" do |_, fmod, sql_type|
precision = extract_precision(sql_type)
scale = extract_scale(sql_type)
# The type for the numeric depends on the width of the field,
# so we'll do something special here.
#
# When dealing with decimal columns:
#
# places after decimal = fmod - 4 & 0xffff
# places before decimal = (fmod - 4) >> 16 & 0xffff
if fmod && (fmod - 4 & 0xffff).zero?
# FIXME: Remove this class, and the second argument to
# lookups on PG
Type::DecimalWithoutScale.new(precision: precision)
else
OID::Decimal.new(precision: precision, scale: scale)
end
end
m.register_type "interval" do |*args, sql_type|
precision = extract_precision(sql_type)
OID::Interval.new(precision: precision)
end
end
end
private
attr_reader :type_map
def initialize_type_map(m = type_map)
self.class.initialize_type_map(m)
self.class.register_class_with_precision m, "time", Type::Time, timezone: @default_timezone
self.class.register_class_with_precision m, "timestamp", OID::Timestamp, timezone: @default_timezone
self.class.register_class_with_precision m, "timestamptz", OID::TimestampWithTimeZone
load_additional_types
end
# Extracts the value from a PostgreSQL column default definition.
def extract_value_from_default(default)
case default
# Quoted types
when /\A[(B]?'(.*)'.*::"?([\w. ]+)"?(?:\[\])?\z/m
# The default 'now'::date is CURRENT_DATE
if $1 == "now" && $2 == "date"
nil
else
$1.gsub("''", "'")
end
# Boolean types
when "true", "false"
default
# Numeric types
when /\A\(?(-?\d+(\.\d*)?)\)?(::bigint)?\z/
$1
# Object identifier types
when /\A-?\d+\z/
$1
else
# Anything else is blank, some user type, or some function
# and we can't know the value of that, so return nil.
nil
end
end
def extract_default_function(default_value, default)
default if has_default_function?(default_value, default)
end
def has_default_function?(default_value, default)
!default_value && %r{\w+\(.*\)|\(.*\)::\w+|CURRENT_DATE|CURRENT_TIMESTAMP}.match?(default)
end
# See https://www.postgresql.org/docs/current/static/errcodes-appendix.html
VALUE_LIMIT_VIOLATION = "22001"
NUMERIC_VALUE_OUT_OF_RANGE = "22003"
NOT_NULL_VIOLATION = "23502"
FOREIGN_KEY_VIOLATION = "23503"
UNIQUE_VIOLATION = "23505"
SERIALIZATION_FAILURE = "40001"
DEADLOCK_DETECTED = "40P01"
DUPLICATE_DATABASE = "42P04"
LOCK_NOT_AVAILABLE = "55P03"
QUERY_CANCELED = "57014"
def translate_exception(exception, message:, sql:, binds:)
return exception unless exception.respond_to?(:result)
case exception.result.try(:error_field, PG::PG_DIAG_SQLSTATE)
when nil
if exception.message.match?(/connection is closed/i)
ConnectionNotEstablished.new(exception, connection_pool: @pool)
elsif exception.is_a?(PG::ConnectionBad)
# libpq message style always ends with a newline; the pg gem's internal
# errors do not. We separate these cases because a pg-internal
# ConnectionBad means it failed before it managed to send the query,
# whereas a libpq failure could have occurred at any time (meaning the
# server may have already executed part or all of the query).
if exception.message.end_with?("\n")
ConnectionFailed.new(exception, connection_pool: @pool)
else
ConnectionNotEstablished.new(exception, connection_pool: @pool)
end
else
super
end
when UNIQUE_VIOLATION
RecordNotUnique.new(message, sql: sql, binds: binds, connection_pool: @pool)
when FOREIGN_KEY_VIOLATION
InvalidForeignKey.new(message, sql: sql, binds: binds, connection_pool: @pool)
when VALUE_LIMIT_VIOLATION
ValueTooLong.new(message, sql: sql, binds: binds, connection_pool: @pool)
when NUMERIC_VALUE_OUT_OF_RANGE
RangeError.new(message, sql: sql, binds: binds, connection_pool: @pool)
when NOT_NULL_VIOLATION
NotNullViolation.new(message, sql: sql, binds: binds, connection_pool: @pool)
when SERIALIZATION_FAILURE
SerializationFailure.new(message, sql: sql, binds: binds, connection_pool: @pool)
when DEADLOCK_DETECTED
Deadlocked.new(message, sql: sql, binds: binds, connection_pool: @pool)
when DUPLICATE_DATABASE
DatabaseAlreadyExists.new(message, sql: sql, binds: binds, connection_pool: @pool)
when LOCK_NOT_AVAILABLE
LockWaitTimeout.new(message, sql: sql, binds: binds, connection_pool: @pool)
when QUERY_CANCELED
QueryCanceled.new(message, sql: sql, binds: binds, connection_pool: @pool)
else
super
end
end
def retryable_query_error?(exception)
# We cannot retry anything if we're inside a broken transaction; we need to at
# least raise until the innermost savepoint is rolled back
@raw_connection&.transaction_status != ::PG::PQTRANS_INERROR &&
super
end
def get_oid_type(oid, fmod, column_name, sql_type = "")
if !type_map.key?(oid)
load_additional_types([oid])
end
type_map.fetch(oid, fmod, sql_type) {
warn "unknown OID #{oid}: failed to recognize type of '#{column_name}'. It will be treated as String."
Type.default_value.tap do |cast_type|
type_map.register_type(oid, cast_type)
end
}
end
def load_additional_types(oids = nil)
initializer = OID::TypeMapInitializer.new(type_map)
load_types_queries(initializer, oids) do |query|
execute_and_clear(query, "SCHEMA", [], allow_retry: true, materialize_transactions: false) do |records|
initializer.run(records)
end
end
end
def load_types_queries(initializer, oids)
query = <<~SQL
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
if oids
yield query + "WHERE t.oid IN (%s)" % oids.join(", ")
else
yield query + initializer.query_conditions_for_known_type_names
yield query + initializer.query_conditions_for_known_type_types
yield query + initializer.query_conditions_for_array_types
end
end
FEATURE_NOT_SUPPORTED = "0A000" # :nodoc:
def execute_and_clear(sql, name, binds, prepare: false, async: false, allow_retry: false, materialize_transactions: true)
sql = transform_query(sql)
check_if_write_query(sql)
if !prepare || without_prepared_statement?(binds)
result = exec_no_cache(sql, name, binds, async: async, allow_retry: allow_retry, materialize_transactions: materialize_transactions)
else
result = exec_cache(sql, name, binds, async: async, allow_retry: allow_retry, materialize_transactions: materialize_transactions)
end
begin
ret = yield result
ensure
result.clear
end
ret
end
def exec_no_cache(sql, name, binds, async:, allow_retry:, materialize_transactions:)
mark_transaction_written_if_write(sql)
# make sure we carry over any changes to ActiveRecord.default_timezone that have been
# made since we established the connection
update_typemap_for_default_timezone
type_casted_binds = type_casted_binds(binds)
log(sql, name, binds, type_casted_binds, async: async) do |notification_payload|
with_raw_connection(allow_retry: allow_retry, materialize_transactions: materialize_transactions) do |conn|
result = conn.exec_params(sql, type_casted_binds)
verified!
notification_payload[:row_count] = result.count
result
end
end
end
def exec_cache(sql, name, binds, async:, allow_retry:, materialize_transactions:)
mark_transaction_written_if_write(sql)
update_typemap_for_default_timezone
with_raw_connection(allow_retry: allow_retry, materialize_transactions: materialize_transactions) do |conn|
stmt_key = prepare_statement(sql, binds, conn)
type_casted_binds = type_casted_binds(binds)
log(sql, name, binds, type_casted_binds, stmt_key, async: async) do |notification_payload|
result = conn.exec_prepared(stmt_key, type_casted_binds)
verified!
notification_payload[:row_count] = result.count
result
end
end
rescue ActiveRecord::StatementInvalid => e
raise unless is_cached_plan_failure?(e)
# Nothing we can do if we are in a transaction because all commands
# will raise InFailedSQLTransaction
if in_transaction?
raise ActiveRecord::PreparedStatementCacheExpired.new(e.cause.message, connection_pool: @pool)
else
@lock.synchronize do
# outside of transactions we can simply flush this query and retry
@statements.delete sql_key(sql)
end
retry
end
end
# Annoyingly, the code for prepared statements whose return value may
# have changed is FEATURE_NOT_SUPPORTED.
#
# This covers various different error types so we need to do additional
# work to classify the exception definitively as a
# ActiveRecord::PreparedStatementCacheExpired
#
# Check here for more details:
# https://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/utils/cache/plancache.c#l573
def is_cached_plan_failure?(e)
pgerror = e.cause
pgerror.result.result_error_field(PG::PG_DIAG_SQLSTATE) == FEATURE_NOT_SUPPORTED &&
pgerror.result.result_error_field(PG::PG_DIAG_SOURCE_FUNCTION) == "RevalidateCachedQuery"
rescue
false
end
def in_transaction?
open_transactions > 0
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, binds, conn)
sql_key = sql_key(sql)
unless @statements.key? sql_key
nextkey = @statements.next_key
begin
conn.prepare nextkey, sql
rescue => e
raise translate_exception_class(e, sql, binds)
end
# Clear the queue
conn.get_last_result
@statements[sql_key] = nextkey
end
@statements[sql_key]
end
# Connects to a PostgreSQL server and sets up the adapter depending on the
# connected server's characteristics.
def connect
@raw_connection = self.class.new_client(@connection_parameters)
rescue ConnectionNotEstablished => ex
raise ex.set_pool(@pool)
end
def reconnect
begin
@raw_connection&.reset
rescue PG::ConnectionBad
@raw_connection = nil
end
connect unless @raw_connection
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
super
if @config[:encoding]
@raw_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]
unless ActiveRecord.db_warnings_action.nil?
@raw_connection.set_notice_receiver do |result|
message = result.error_field(PG::Result::PG_DIAG_MESSAGE_PRIMARY)
code = result.error_field(PG::Result::PG_DIAG_SQLSTATE)
level = result.error_field(PG::Result::PG_DIAG_SEVERITY)
@notice_receiver_sql_warnings << SQLWarning.new(message, code, level, nil, @pool)
end
end
# Use standard-conforming strings so we don't have to do the E'...' dance.
set_standard_conforming_strings
variables = @config.fetch(:variables, {}).stringify_keys
# Set interval output format to ISO 8601 for ease of parsing by ActiveSupport::Duration.parse
internal_execute("SET intervalstyle = iso_8601")
# SET statements from :variables config hash
# https://www.postgresql.org/docs/current/static/sql-set.html
variables.map do |k, v|
if v == ":default" || v == :default
# Sets the value to the global or compile default
internal_execute("SET SESSION #{k} TO DEFAULT")
elsif !v.nil?
internal_execute("SET SESSION #{k} TO #{quote(v)}")
end
end
add_pg_encoders
add_pg_decoders
reload_type_map
end
def reconfigure_connection_timezone
variables = @config.fetch(:variables, {}).stringify_keys
# If it's been directly configured as a connection variable, we don't
# need to do anything here; it will be set up by configure_connection
# and then never changed.
return if variables["timezone"]
# If using Active Record's time zone support configure the connection
# to return TIMESTAMP WITH ZONE types in UTC.
if default_timezone == :utc
internal_execute("SET SESSION timezone TO 'UTC'")
else
internal_execute("SET SESSION timezone TO DEFAULT")
end
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, column.comment
# 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)
query(<<~SQL, "SCHEMA")
SELECT a.attname, format_type(a.atttypid, a.atttypmod),
pg_get_expr(d.adbin, d.adrelid), a.attnotnull, a.atttypid, a.atttypmod,
c.collname, col_description(a.attrelid, a.attnum) AS comment,
#{supports_identity_columns? ? 'attidentity' : quote('')} AS identity,
#{supports_virtual_columns? ? 'attgenerated' : quote('')} as attgenerated
FROM pg_attribute a
LEFT JOIN pg_attrdef d ON a.attrelid = d.adrelid AND a.attnum = d.adnum
LEFT JOIN pg_type t ON a.atttypid = t.oid
LEFT JOIN pg_collation c ON a.attcollation = c.oid AND a.attcollation <> t.typcollation
WHERE a.attrelid = #{quote(quote_table_name(table_name))}::regclass
AND a.attnum > 0 AND NOT a.attisdropped
ORDER BY a.attnum
SQL
end
def arel_visitor
Arel::Visitors::PostgreSQL.new(self)
end
def build_statement_pool
StatementPool.new(self, self.class.type_cast_config_to_integer(@config[:statement_limit]))
end
def can_perform_case_insensitive_comparison_for?(column)
# NOTE: citext is an exception. It is possible to perform a
# case-insensitive comparison using `LOWER()`, but it is
# unnecessary, as `citext` is case-insensitive by definition.
@case_insensitive_cache ||= { "citext" => false }
@case_insensitive_cache.fetch(column.sql_type) do
@case_insensitive_cache[column.sql_type] = begin
sql = <<~SQL
SELECT exists(
SELECT * FROM pg_proc
WHERE proname = 'lower'
AND proargtypes = ARRAY[#{quote column.sql_type}::regtype]::oidvector
) OR exists(
SELECT * FROM pg_proc
INNER JOIN pg_cast
ON ARRAY[casttarget]::oidvector = proargtypes
WHERE proname = 'lower'
AND castsource = #{quote column.sql_type}::regtype
)
SQL
execute_and_clear(sql, "SCHEMA", [], allow_retry: true, materialize_transactions: false) do |result|
result.getvalue(0, 0)
end
end
end
end
def add_pg_encoders
map = PG::TypeMapByClass.new
map[Integer] = PG::TextEncoder::Integer.new
map[TrueClass] = PG::TextEncoder::Boolean.new
map[FalseClass] = PG::TextEncoder::Boolean.new
@raw_connection.type_map_for_queries = map
end
def update_typemap_for_default_timezone
if @raw_connection && @mapped_default_timezone != default_timezone && @timestamp_decoder
decoder_class = default_timezone == :utc ?
PG::TextDecoder::TimestampUtc :
PG::TextDecoder::TimestampWithoutTimeZone
@timestamp_decoder = decoder_class.new(**@timestamp_decoder.to_h)
@raw_connection.type_map_for_results.add_coder(@timestamp_decoder)
@mapped_default_timezone = default_timezone
# if default timezone has changed, we need to reconfigure the connection
# (specifically, the session time zone)
reconfigure_connection_timezone
true
end
end
def add_pg_decoders
@mapped_default_timezone = nil
@timestamp_decoder = nil
coders_by_name = {
"int2" => PG::TextDecoder::Integer,
"int4" => PG::TextDecoder::Integer,
"int8" => PG::TextDecoder::Integer,
"oid" => PG::TextDecoder::Integer,
"float4" => PG::TextDecoder::Float,
"float8" => PG::TextDecoder::Float,
"numeric" => PG::TextDecoder::Numeric,
"bool" => PG::TextDecoder::Boolean,
"timestamp" => PG::TextDecoder::TimestampUtc,
"timestamptz" => PG::TextDecoder::TimestampWithTimeZone,
}
known_coder_types = coders_by_name.keys.map { |n| quote(n) }
query = <<~SQL % known_coder_types.join(", ")
SELECT t.oid, t.typname
FROM pg_type as t
WHERE t.typname IN (%s)
SQL
coders = execute_and_clear(query, "SCHEMA", [], allow_retry: true, materialize_transactions: false) do |result|
result.filter_map { |row| construct_coder(row, coders_by_name[row["typname"]]) }
end
map = PG::TypeMapByOid.new
coders.each { |coder| map.add_coder(coder) }
@raw_connection.type_map_for_results = map
@type_map_for_results = PG::TypeMapByOid.new
@type_map_for_results.default_type_map = map
@type_map_for_results.add_coder(PG::TextDecoder::Bytea.new(oid: 17, name: "bytea"))
@type_map_for_results.add_coder(MoneyDecoder.new(oid: 790, name: "money"))
# extract timestamp decoder for use in update_typemap_for_default_timezone
@timestamp_decoder = coders.find { |coder| coder.name == "timestamp" }
update_typemap_for_default_timezone
end
def construct_coder(row, coder_class)
return unless coder_class
coder_class.new(oid: row["oid"].to_i, name: row["typname"])
end
class MoneyDecoder < PG::SimpleDecoder # :nodoc:
TYPE = OID::Money.new
def decode(value, tuple = nil, field = nil)
TYPE.deserialize(value)
end
end
ActiveRecord::Type.add_modifier({ array: true }, OID::Array, adapter: :postgresql)
ActiveRecord::Type.add_modifier({ range: true }, OID::Range, adapter: :postgresql)
ActiveRecord::Type.register(:bit, OID::Bit, adapter: :postgresql)
ActiveRecord::Type.register(:bit_varying, OID::BitVarying, adapter: :postgresql)
ActiveRecord::Type.register(:binary, OID::Bytea, adapter: :postgresql)
ActiveRecord::Type.register(:cidr, OID::Cidr, adapter: :postgresql)
ActiveRecord::Type.register(:date, OID::Date, adapter: :postgresql)
ActiveRecord::Type.register(:datetime, OID::DateTime, adapter: :postgresql)
ActiveRecord::Type.register(:decimal, OID::Decimal, adapter: :postgresql)
ActiveRecord::Type.register(:enum, OID::Enum, adapter: :postgresql)
ActiveRecord::Type.register(:hstore, OID::Hstore, adapter: :postgresql)
ActiveRecord::Type.register(:inet, OID::Inet, adapter: :postgresql)
ActiveRecord::Type.register(:interval, OID::Interval, adapter: :postgresql)
ActiveRecord::Type.register(:jsonb, OID::Jsonb, adapter: :postgresql)
ActiveRecord::Type.register(:money, OID::Money, adapter: :postgresql)
ActiveRecord::Type.register(:point, OID::Point, adapter: :postgresql)
ActiveRecord::Type.register(:legacy_point, OID::LegacyPoint, adapter: :postgresql)
ActiveRecord::Type.register(:uuid, OID::Uuid, adapter: :postgresql)
ActiveRecord::Type.register(:vector, OID::Vector, adapter: :postgresql)
ActiveRecord::Type.register(:xml, OID::Xml, adapter: :postgresql)
end
ActiveSupport.run_load_hooks(:active_record_postgresqladapter, PostgreSQLAdapter)
end
end