Class: DB::Postgres::Connection

Inherits:
Async::Pool::Resource
  • Object
show all
Defined in:
lib/db/postgres/connection.rb

Overview

A high-level database connection that implements the standardized connection interface. This class provides a bridge between the underlying native PostgreSQL interface and the DB gem’s unified connection API.

Constant Summary collapse

FEATURES = 
DB::Features.new(
	alter_column_type: true,
	using_clause: true,
	conditional_operations: true,
	transactional_schema: true,
	batch_alter_table: true,
	concurrent_schema: true,
	serial_columns: true,
)

Instance Method Summary collapse

Constructor Details

#initialize(**options) ⇒ Connection

Initialize a new database connection.



17
18
19
20
21
 
# File 'lib/db/postgres/connection.rb', line 17

def initialize(**options)
	@native = Native::Connection.connect(**options)
	
	super()
end

Instance Method Details

#append_identifier(value, buffer = String.new) ⇒ Object

Append an escaped identifier to the buffer.



76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
 
# File 'lib/db/postgres/connection.rb', line 76

def append_identifier(value, buffer = String.new)
	case value
	when Array
		first = true
		value.each do |part|
			buffer << "." unless first
			first = false
			
			buffer << @native.escape_identifier(part)
		end
	else
		buffer << @native.escape_identifier(value)
	end
	
	return buffer
end

#append_literal(value, buffer = String.new) ⇒ Object

Append a literal value to the buffer with appropriate formatting.



53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
 
# File 'lib/db/postgres/connection.rb', line 53

def append_literal(value, buffer = String.new)
	case value
	when Time, DateTime, Date
		append_string(value.iso8601, buffer)
	when Numeric
		buffer << value.to_s
	when TrueClass
		buffer << "TRUE"
	when FalseClass
		buffer << "FALSE"
	when nil
		buffer << "NULL"
	else
		append_string(value, buffer)
	end
	
	return buffer
end

#append_string(value, buffer = String.new) ⇒ Object

Append an escaped string value to the buffer.



43
44
45
46
47
 
# File 'lib/db/postgres/connection.rb', line 43

def append_string(value, buffer = String.new)
	buffer << @native.escape_literal(value)
	
	return buffer
end

#close ⇒ Object

Close the database connection and release resources.



24
25
26
27
28
29
30
31
 
# File 'lib/db/postgres/connection.rb', line 24

def close
	if @native
		@native&.close
		@native = nil
	end
	
	super
end

#features ⇒ Object

Database feature detection for migration and query building.



150
151
152
 
# File 'lib/db/postgres/connection.rb', line 150

def features
	FEATURES
end

#key_column(name = "id", primary: true, null: false) ⇒ Object

Generate a key column definition for table creation.



98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
 
# File 'lib/db/postgres/connection.rb', line 98

def key_column(name = "id", primary: true, null: false)
	buffer = String.new
	
	append_identifier(name, buffer)
	
	if primary
		buffer << " BIGSERIAL"
	else
		buffer << " BIGINT"
	end
	
	if primary
		buffer << " PRIMARY KEY"
	elsif !null
		buffer << " NOT NULL"
	end
	
	return buffer
end

#next_result ⇒ Object

Get the next result set from a multi-result query.



134
135
136
 
# File 'lib/db/postgres/connection.rb', line 134

def next_result
	@native.next_result
end

#send_query(statement) ⇒ Object

Send a query to the database server.



126
127
128
129
130
 
# File 'lib/db/postgres/connection.rb', line 126

def send_query(statement)
	@native.discard_results
	
	@native.send_query(statement)
end

#status ⇒ Object

Get the current connection status.



120
121
122
 
# File 'lib/db/postgres/connection.rb', line 120

def status
	@native.status
end

#types ⇒ Object

Get the type mapping for database types.



35
36
37
 
# File 'lib/db/postgres/connection.rb', line 35

def types
	@native.types
end