Class: PG::BasicTypeRegistry

Inherits:
Object
  • Object
show all
Includes:
Checker
Defined in:
lib/pg/basic_type_registry.rb

Overview

This class defines the mapping between PostgreSQL types and encoder/decoder classes for PG::BasicTypeMapForResults, PG::BasicTypeMapForQueries and PG::BasicTypeMapBasedOnResult.

Additional types can be added like so:

require 'pg'
require 'ipaddr'

class InetDecoder < PG::SimpleDecoder
  def decode(string, tuple=nil, field=nil)
    IPAddr.new(string)
  end
end
class InetEncoder < PG::SimpleEncoder
  def encode(ip_addr)
    ip_addr.to_s
  end
end

conn = PG.connect
regi = PG::BasicTypeRegistry.new.register_default_types
regi.register_type(0, 'inet', InetEncoder, InetDecoder)
conn.type_map_for_results = PG::BasicTypeMapForResults.new(conn, registry: regi)

Defined Under Namespace

Modules: Checker Classes: CoderMap, CoderMapsBundle

Instance Method Summary collapse

Constructor Details

#initialize ⇒ BasicTypeRegistry

Returns a new instance of BasicTypeRegistry.



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# File 'lib/pg/basic_type_registry.rb', line 173

def initialize
	# @coders_by_name has a content of
	#    Array< Hash< Symbol: Hash< String: Coder > > >
	#
	# The layers are:
	#   * index of Array is 0 (text) and 1 (binary)
	#   * Symbol key in the middle Hash is :encoder and :decoder
	#   * String key in the inner Hash corresponds to the `typname` column in the table pg_type
	#   * Coder value in the inner Hash is the associated coder object
	@coders_by_name = []
end

Instance Method Details

#alias_type(format, new, old) ⇒ Object

Alias the old type to the new type.



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# File 'lib/pg/basic_type_registry.rb', line 216

def alias_type(format, new, old)
	[:encoder, :decoder].each do |ende|
		enc = @coders_by_name[format][ende][old]
		if enc
			@coders_by_name[format][ende][new] = enc
		else
			@coders_by_name[format][ende].delete(new)
		end
	end
	self
end

#coders_for(format, direction) ⇒ Object

Retrieve a Hash of all en- or decoders for a given wire format. The hash key is the name as defined in table pg_type. The hash value is the registered coder object.



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# File 'lib/pg/basic_type_registry.rb', line 188

def coders_for(format, direction)
	check_format_and_direction(format, direction)
	@coders_by_name[format]&.[](direction)
end

#register_coder(coder) ⇒ Object

Register an encoder or decoder instance for casting a PostgreSQL type.

Coder#name must correspond to the typname column in the pg_type table. Coder#format can be 0 for text format and 1 for binary.



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# File 'lib/pg/basic_type_registry.rb', line 197

def register_coder(coder)
	h = @coders_by_name[coder.format] ||= { encoder: {}, decoder: {} }
	name = coder.name || raise(ArgumentError, "name of #{coder.inspect} must be defined")
	h[:encoder][name] = coder if coder.respond_to?(:encode)
	h[:decoder][name] = coder if coder.respond_to?(:decode)
	self
end

#register_default_types ⇒ Object Also known as: define_default_types

Populate the registry with all builtin types of ruby-pg



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# File 'lib/pg/basic_type_registry.rb', line 229

def register_default_types
	register_type 0, 'int2', PG::TextEncoder::Integer, PG::TextDecoder::Integer
	alias_type    0, 'int4', 'int2'
	alias_type    0, 'int8', 'int2'
	alias_type    0, 'oid',  'int2'

	begin
		PG.require_bigdecimal_without_warning
		register_type 0, 'numeric', PG::TextEncoder::Numeric, PG::TextDecoder::Numeric
	rescue LoadError
	end
	register_type 0, 'text', PG::TextEncoder::String, PG::TextDecoder::String
	alias_type 0, 'varchar', 'text'
	alias_type 0, 'char', 'text'
	alias_type 0, 'bpchar', 'text'
	alias_type 0, 'xml', 'text'
	alias_type 0, 'name', 'text'

	# FIXME: why are we keeping these types as strings?
	# alias_type 'tsvector', 'text'
	# alias_type 'interval', 'text'
	# alias_type 'macaddr',  'text'
	# alias_type 'uuid',     'text'
	#
	# register_type 'money', OID::Money.new
	register_type 0, 'bytea', PG::TextEncoder::Bytea, PG::TextDecoder::Bytea
	register_type 0, 'bool', PG::TextEncoder::Boolean, PG::TextDecoder::Boolean
	# register_type 'bit', OID::Bit.new
	# register_type 'varbit', OID::Bit.new

	register_type 0, 'float4', PG::TextEncoder::Float, PG::TextDecoder::Float
	alias_type 0, 'float8', 'float4'

	# For compatibility reason the timestamp in text format is encoded as local time (TimestampWithoutTimeZone) instead of UTC
	register_type 0, 'timestamp', PG::TextEncoder::TimestampWithoutTimeZone, PG::TextDecoder::TimestampWithoutTimeZone
	register_type 0, 'timestamptz', PG::TextEncoder::TimestampWithTimeZone, PG::TextDecoder::TimestampWithTimeZone
	register_type 0, 'date', PG::TextEncoder::Date, PG::TextDecoder::Date
	# register_type 'time', OID::Time.new
	#
	# register_type 'path', OID::Text.new
	# register_type 'point', OID::Point.new
	# register_type 'polygon', OID::Text.new
	# register_type 'circle', OID::Text.new
	# register_type 'hstore', OID::Hstore.new
	register_type 0, 'json', PG::TextEncoder::JSON, PG::TextDecoder::JSON
	alias_type    0, 'jsonb',  'json'
	# register_type 'citext', OID::Text.new
	# register_type 'ltree', OID::Text.new
	#
	register_type 0, 'inet', PG::TextEncoder::Inet, PG::TextDecoder::Inet
	alias_type 0, 'cidr', 'inet'

	register_type 0, 'record', PG::TextEncoder::Record, PG::TextDecoder::Record


	register_type 1, 'int2', PG::BinaryEncoder::Int2, PG::BinaryDecoder::Integer
	register_type 1, 'int4', PG::BinaryEncoder::Int4, PG::BinaryDecoder::Integer
	register_type 1, 'int8', PG::BinaryEncoder::Int8, PG::BinaryDecoder::Integer
	alias_type    1, 'oid',  'int2'

	register_type 1, 'text', PG::BinaryEncoder::String, PG::BinaryDecoder::String
	alias_type 1, 'varchar', 'text'
	alias_type 1, 'char', 'text'
	alias_type 1, 'bpchar', 'text'
	alias_type 1, 'xml', 'text'
	alias_type 1, 'name', 'text'

	register_type 1, 'bytea', PG::BinaryEncoder::Bytea, PG::BinaryDecoder::Bytea
	register_type 1, 'bool', PG::BinaryEncoder::Boolean, PG::BinaryDecoder::Boolean
	register_type 1, 'float4', PG::BinaryEncoder::Float4, PG::BinaryDecoder::Float
	register_type 1, 'float8', PG::BinaryEncoder::Float8, PG::BinaryDecoder::Float
	register_type 1, 'timestamp', PG::BinaryEncoder::TimestampUtc, PG::BinaryDecoder::TimestampUtc
	register_type 1, 'timestamptz', PG::BinaryEncoder::TimestampUtc, PG::BinaryDecoder::TimestampUtcToLocal
	register_type 1, 'date', PG::BinaryEncoder::Date, PG::BinaryDecoder::Date

	self
end

#register_type(format, name, encoder_class, decoder_class) ⇒ Object

Register the given encoder_class and/or decoder_class for casting a PostgreSQL type.

name must correspond to the typname column in the pg_type table. format can be 0 for text format and 1 for binary.



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# File 'lib/pg/basic_type_registry.rb', line 209

def register_type(format, name, encoder_class, decoder_class)
	register_coder(encoder_class.new(name: name, format: format).freeze) if encoder_class
	register_coder(decoder_class.new(name: name, format: format).freeze) if decoder_class
	self
end