Sequel doesn’t pay much attention to timezones by default, but you can set it to handle timezones if you want. There are three separate timezone settings:
All three timezones have getter and setter methods. You can set all three timezones to the same value at once via Sequel.default_timezone=.
The only timezone values that are supported by default are :utc (convert to UTC), :local (convert to local time), and nil (don’t convert). If you need to convert to a specific timezone, or need the timezones being used to change based on the environment (e.g. current user), you need to use the named_timezones extension (and use DateTime as the datetime_class). Sequel also ships with a thread_local_timezones extensions which allows each thread to have its own timezone values for each of the timezones.
Methods
Public Instance
- application_timezone
- application_to_database_timestamp
- array_or_set_join
- condition_specifier?
- connect
- convert_exception_class
- convert_output_timestamp
- convert_timestamp
- convert_two_digit_years
- core_extensions?
- current
- database_timezone
- database_to_application_timestamp
- datetime_class
- default_timezone=
- elapsed_seconds_since
- extension
- json_parser_error_class
- object_to_json
- parse_json
- recursive_map
- require
- set_temp_name
- single_threaded
- split_symbol
- split_symbols=
- split_symbols?
- start_timer
- string_to_date
- string_to_datetime
- string_to_time
- synchronize
- synchronize_with
- transaction
- typecast_timezone
- typecast_to_application_timestamp
- virtual_row
Public Instance Aliases
| orig_require | -> | require |
Alias of original require method, as Sequel.require does a relative require for backwards compatibility. |
Attributes
| application_timezone | [R] |
The timezone you want the application to use. This is the timezone that incoming times from the database and typecasting are converted to. |
| convert_two_digit_years | [RW] |
Sequel.convert_two_digit_years = false |
| database_timezone | [R] |
The timezone for storage in the database. This is the timezone to which |
| datetime_class | [RW] |
Sequel.datetime_class = DateTime Note that |
| single_threaded | [RW] |
Set whether Sequel.single_threaded = true |
| typecast_timezone | [R] |
The timezone that incoming data that |
Public Instance methods
Convert the given Time/DateTime object into the database timezone, used when literalizing objects in an SQL string.
# File lib/sequel/timezones.rb 50 def application_to_database_timestamp(v) 51 convert_output_timestamp(v, Sequel.database_timezone) 52 end
Join the array or set.
# File lib/sequel/core.rb 169 def array_or_set_join(obj, arg) 170 obj.join(arg) 171 end
Returns true if the passed object could be a specifier of conditions, false otherwise. Currently, Sequel considers hashes and arrays of two element arrays as condition specifiers.
Sequel.condition_specifier?({}) # => true Sequel.condition_specifier?([[1, 2]]) # => true Sequel.condition_specifier?([]) # => false Sequel.condition_specifier?([1]) # => false Sequel.condition_specifier?(1) # => false
# File lib/sequel/core.rb 83 def condition_specifier?(obj) 84 case obj 85 when Hash 86 true 87 when Array 88 !obj.empty? && !obj.is_a?(SQL::ValueList) && obj.all?{|i| i.is_a?(Array) && (i.length == 2)} 89 else 90 false 91 end 92 end
Creates a new database object based on the supplied connection string and optional arguments. The specified scheme determines the database class used, and the rest of the string specifies the connection options. For example:
DB = Sequel.connect('sqlite:/') # Memory database DB = Sequel.connect('sqlite://blog.db') # ./blog.db DB = Sequel.connect('sqlite:///blog.db') # /blog.db DB = Sequel.connect('postgres://user:password@host:port/database_name') DB = Sequel.connect('sqlite:///blog.db', max_connections: 10)
You can also pass a single options hash:
DB = Sequel.connect(adapter: 'sqlite', database: './blog.db')
If a block is given, it is passed the opened Database object, which is closed when the block exits. For example:
Sequel.connect('sqlite://blog.db'){|db| puts db[:users].count}
If a block is not given, a reference to this database will be held in Sequel::DATABASES until it is removed manually. This is by design, and used by Sequel::Model to pick the default database. It is recommended to pass a block if you do not want the resulting Database object to remain in memory until the process terminates, or use the keep_reference: false Database option.
For details, see the “Connecting to a Database” guide. To set up a primary/replica or sharded database connection, see the “Primary/Replica Database Configurations and Sharding” guide.
# File lib/sequel/core.rb 123 def connect(*args, &block) 124 Database.connect(*args, &block) 125 end
Convert the exception to the given class. The given class should be Sequel::Error or a subclass. Returns an instance of klass with the message and backtrace of exception.
# File lib/sequel/core.rb 136 def convert_exception_class(exception, klass) 137 return exception if exception.is_a?(klass) 138 e = klass.new("#{exception.class}: #{exception.message}") 139 e.wrapped_exception = exception 140 e.set_backtrace(exception.backtrace) 141 e 142 end
Converts the object to the given output_timezone.
# File lib/sequel/timezones.rb 55 def convert_output_timestamp(v, output_timezone) 56 if output_timezone 57 if v.is_a?(DateTime) 58 case output_timezone 59 when :utc 60 v.new_offset(0) 61 when :local 62 v.new_offset(local_offset_for_datetime(v)) 63 else 64 convert_output_datetime_other(v, output_timezone) 65 end 66 else 67 case output_timezone 68 when :utc 69 v.getutc 70 when :local 71 v.getlocal 72 else 73 convert_output_time_other(v, output_timezone) 74 end 75 end 76 else 77 v 78 end 79 end
Converts the given object from the given input timezone to the application_timezone using convert_input_timestamp and convert_output_timestamp.
# File lib/sequel/timezones.rb 84 def convert_timestamp(v, input_timezone) 85 if v.is_a?(Date) && !v.is_a?(DateTime) 86 # Dates handled specially as they are assumed to already be in the application_timezone 87 if datetime_class == DateTime 88 DateTime.civil(v.year, v.month, v.day, 0, 0, 0, application_timezone == :local ? Rational(Time.local(v.year, v.month, v.day).utc_offset, 86400) : 0) 89 else 90 Time.public_send(application_timezone == :utc ? :utc : :local, v.year, v.month, v.day) 91 end 92 else 93 convert_output_timestamp(convert_input_timestamp(v, input_timezone), application_timezone) 94 end 95 rescue InvalidValue 96 raise 97 rescue => e 98 raise convert_exception_class(e, InvalidValue) 99 end
Assume the core extensions are not loaded by default, if the core_extensions extension is loaded, this will be overridden.
# File lib/sequel/core.rb 129 def core_extensions? 130 false 131 end
The current concurrency primitive, Thread.current by default.
# File lib/sequel/core.rb 145 def current 146 Thread.current 147 end
Convert the given object into an object of Sequel.datetime_class in the application_timezone. Used when converting datetime/timestamp columns returned by the database.
# File lib/sequel/timezones.rb 104 def database_to_application_timestamp(v) 105 convert_timestamp(v, Sequel.database_timezone) 106 end
Sets the database, application, and typecasting timezones to the given timezone.
# File lib/sequel/timezones.rb 109 def default_timezone=(tz) 110 self.database_timezone = tz 111 self.application_timezone = tz 112 self.typecast_timezone = tz 113 end
The elapsed seconds since the given timer object was created. The timer object should have been created via Sequel.start_timer.
# File lib/sequel/core.rb 364 def elapsed_seconds_since(timer) 365 start_timer - timer 366 end
Load all Sequel extensions given. Extensions are just files that exist under sequel/extensions in the load path, and are just required.
In some cases, requiring an extension modifies classes directly, and in others, it just loads a module that you can extend other classes with. Consult the documentation for each extension you plan on using for usage.
Sequel.extension(:blank) Sequel.extension(:core_extensions, :named_timezones)
# File lib/sequel/core.rb 157 def extension(*extensions) 158 extensions.each{|e| orig_require("sequel/extensions/#{e}")} 159 end
The exception classed raised if there is an error parsing JSON. This can be overridden to use an alternative json implementation.
# File lib/sequel/core.rb 163 def json_parser_error_class 164 JSON::ParserError 165 end
Convert given object to json and return the result. This can be overridden to use an alternative json implementation.
# File lib/sequel/core.rb 198 def object_to_json(obj, *args, &block) 199 obj.to_json(*args, &block) 200 end
Parse the string as JSON and return the result. This can be overridden to use an alternative json implementation.
# File lib/sequel/core.rb 204 def parse_json(json) 205 JSON.parse(json, :create_additions=>false) 206 end
Convert each item in the array to the correct type, handling multi-dimensional arrays. For each element in the array or subarrays, call the converter, unless the value is nil.
# File lib/sequel/core.rb 222 def recursive_map(array, converter) 223 array.map do |i| 224 if i.is_a?(Array) 225 recursive_map(i, converter) 226 elsif !i.nil? 227 converter.call(i) 228 end 229 end 230 end
For backwards compatibility only. require_relative should be used instead.
# File lib/sequel/core.rb 233 def require(files, subdir=nil) 234 # Use Kernel.require_relative to work around JRuby 9.0 bug 235 Array(files).each{|f| Kernel.require_relative "#{"#{subdir}/" if subdir}#{f}"} 236 end
Create a new module using the block, and set the temporary name on it using the given a containing module and name.
# File lib/sequel/core.rb 184 def set_temp_name(mod) 185 mod.set_temporary_name(yield) 186 mod 187 end
Splits the symbol into three parts, if symbol splitting is enabled (not the default). Each part will either be a string or nil. If symbol splitting is disabled, returns an array with the first and third parts being nil, and the second part beind a string version of the symbol.
For columns, these parts are the table, column, and alias. For tables, these parts are the schema, table, and alias.
# File lib/sequel/core.rb 245 def split_symbol(sym) 246 unless v = Sequel.synchronize{SPLIT_SYMBOL_CACHE[sym]} 247 if split_symbols? 248 v = case s = sym.to_s 249 when /\A((?:(?!__).)+)__((?:(?!___).)+)___(.+)\z/ 250 [$1.freeze, $2.freeze, $3.freeze].freeze 251 when /\A((?:(?!___).)+)___(.+)\z/ 252 [nil, $1.freeze, $2.freeze].freeze 253 when /\A((?:(?!__).)+)__(.+)\z/ 254 [$1.freeze, $2.freeze, nil].freeze 255 else 256 [nil, s.freeze, nil].freeze 257 end 258 else 259 v = [nil,sym.to_s.freeze,nil].freeze 260 end 261 Sequel.synchronize{SPLIT_SYMBOL_CACHE[sym] = v} 262 end 263 v 264 end
Setting this to true enables Sequel’s historical behavior of splitting symbols on double or triple underscores:
:table__column # table.column :column___alias # column AS alias :table__column___alias # table.column AS alias
It is only recommended to turn this on for backwards compatibility until such symbols have been converted to use newer Sequel APIs such as:
Sequel[:table][:column] # table.column Sequel[:column].as(:alias) # column AS alias Sequel[:table][:column].as(:alias) # table.column AS alias
Sequel::Database instances do their own caching of literalized symbols, and changing this setting does not affect those caches. It is recommended that if you want to change this setting, you do so directly after requiring Sequel, before creating any Sequel::Database instances.
Disabling symbol splitting will also disable the handling of double underscores in virtual row methods, causing such methods to yield regular identifers instead of qualified identifiers:
# Sequel.split_symbols = true Sequel.expr{table__column} # table.column Sequel.expr{table[:column]} # table.column # Sequel.split_symbols = false Sequel.expr{table__column} # table__column Sequel.expr{table[:column]} # table.column
# File lib/sequel/core.rb 296 def split_symbols=(v) 297 Sequel.synchronize{SPLIT_SYMBOL_CACHE.clear} 298 @split_symbols = v 299 end
Whether Sequel currently splits symbols into qualified/aliased identifiers.
# File lib/sequel/core.rb 302 def split_symbols? 303 @split_symbols 304 end
A timer object that can be passed to Sequel.elapsed_seconds_since to return the number of seconds elapsed.
# File lib/sequel/core.rb 351 def start_timer 352 Process.clock_gettime(Process::CLOCK_MONOTONIC) 353 end
Converts the given string into a Date object.
Sequel.string_to_date('2010-09-10') # Date.civil(2010, 09, 10)
# File lib/sequel/core.rb 309 def string_to_date(string) 310 Date.parse(string, Sequel.convert_two_digit_years) 311 rescue => e 312 raise convert_exception_class(e, InvalidValue) 313 end
Converts the given string into a Time or DateTime object, depending on the value of Sequel.datetime_class.
Sequel.string_to_datetime('2010-09-10 10:20:30') # Time.local(2010, 09, 10, 10, 20, 30)
# File lib/sequel/core.rb 319 def string_to_datetime(string) 320 if datetime_class == DateTime 321 DateTime.parse(string, convert_two_digit_years) 322 else 323 datetime_class.parse(string) 324 end 325 rescue => e 326 raise convert_exception_class(e, InvalidValue) 327 end
Converts the given string into a Sequel::SQLTime object.
v = Sequel.string_to_time('10:20:30') # Sequel::SQLTime.parse('10:20:30') DB.literal(v) # => '10:20:30'
# File lib/sequel/core.rb 333 def string_to_time(string) 334 SQLTime.parse(string) 335 rescue => e 336 raise convert_exception_class(e, InvalidValue) 337 end
Unless in single threaded mode, protects access to any mutable global data structure in Sequel. Uses a non-reentrant mutex, so calling code should be careful. In general, this should only be used around the minimal possible code such as Hash#[], Hash#[]=, Hash#delete, Array#<<, and Array#delete.
# File lib/sequel/core.rb 344 def synchronize(&block) 345 @single_threaded ? yield : @data_mutex.synchronize(&block) 346 end
If a mutex is given, synchronize access using it. If nil is given, just yield to the block. This is designed for cases where a mutex may or may not be provided.
# File lib/sequel/core.rb 211 def synchronize_with(mutex) 212 if mutex 213 mutex.synchronize{yield} 214 else 215 yield 216 end 217 end
Uses a transaction on all given databases with the given options. This:
Sequel.transaction([DB1, DB2, DB3]){}
is equivalent to:
DB1.transaction do DB2.transaction do DB3.transaction do end end end
except that if Sequel::Rollback is raised by the block, the transaction is rolled back on all databases instead of just the last one.
Note that this method cannot guarantee that all databases will commit or rollback. For example, if DB3 commits but attempting to commit on DB2 fails (maybe because foreign key checks are deferred), there is no way to uncommit the changes on DB3. For that kind of support, you need to have two-phase commit/prepared transactions (which Sequel supports on some databases).
# File lib/sequel/core.rb 390 def transaction(dbs, opts=OPTS, &block) 391 unless opts[:rollback] 392 rescue_rollback = true 393 opts = Hash[opts].merge!(:rollback=>:reraise) 394 end 395 pr = dbs.reverse.inject(block){|bl, db| proc{db.transaction(opts, &bl)}} 396 if rescue_rollback 397 begin 398 pr.call 399 rescue Sequel::Rollback 400 nil 401 end 402 else 403 pr.call 404 end 405 end
Convert the given object into an object of Sequel.datetime_class in the application_timezone. Used when typecasting values when assigning them to model datetime attributes.
# File lib/sequel/timezones.rb 118 def typecast_to_application_timestamp(v) 119 convert_timestamp(v, Sequel.typecast_timezone) 120 end
If the supplied block takes a single argument, yield an SQL::VirtualRow instance to the block argument. Otherwise, evaluate the block in the context of a SQL::VirtualRow instance.
Sequel.virtual_row{a} # Sequel::SQL::Identifier.new(:a) Sequel.virtual_row{|o| o.a} # Sequel::SQL::Function.new(:a)
# File lib/sequel/core.rb 414 def virtual_row(&block) 415 vr = VIRTUAL_ROW 416 case block.arity 417 when -1, 0 418 vr.instance_exec(&block) 419 else 420 yield(vr) 421 end 422 end