View Source Cldr.Eternal (Cldr Currencies v2.16.0)

This module implements bindings around what should be an eternal ETS table, or at least until you decide to terminate it. It works by using "bouncing" GenServers which come up as needed to provide an heir for the ETS table. It operates as follows:

An ETS table is created with the provided name and options.
Two GenServers are started, an owner and an heir. The ETS table is gifted to the owner, and has the heir set as the heir.
If the owner crashes, the heir becomes the owner, and a new GenServer is started and assigned the role of heir.
If an heir dies, we attempt to start a new GenServer and notify the owner so that they may change the assigned heir.

This means that there should always be an heir to your table, which should ensure that you don't lose anything inside ETS.

Summary

Types

on_start()

table()

Functions

heir(table)

Returns the heir of a given ETS table.

owner(table)

Returns the owner of a given ETS table.

start(name, ets_opts \\ [], opts \\ [])

Functionally equivalent to start_link/3, except that the link to the starting process is removed after the table is started.

start_link(name, ets_opts \\ [], opts \\ [])

Creates a new ETS table using the provided ets_opts.

stop(table)

Terminates both servers in charge of a given ETS table.

Types

on_start()

@type on_start() ::
  {:ok, pid()}
  | :ignore
  | {:error, {:already_started, pid()} | {:shutdown, term()} | term()}

table()

@type table() :: :ets.table()

Functions

heir(table)

@spec heir(table :: table()) :: any()

Returns the heir of a given ETS table.

Examples

iex> Cldr.Eternal.heir(:my_table)

owner(table)

@spec owner(table :: table()) :: any()

Returns the owner of a given ETS table.

Examples

iex> Cldr.Eternal.owner(:my_table)

start(name, ets_opts \\ [], opts \\ [])

@spec start(name :: atom(), ets_opts :: list(), opts :: Keyword.t()) :: on_start()

Functionally equivalent to start_link/3, except that the link to the starting process is removed after the table is started.

Examples

iex> Cldr.Eternal.start(:table1, [], [quiet: true])

iex> Cldr.Eternal.start(:table2, [:compressed], [quiet: true])

iex> Cldr.Eternal.start(:table3, [], [quiet: true])

start_link(name, ets_opts \\ [], opts \\ [])

@spec start_link(name :: atom(), ets_opts :: list(), opts :: Keyword.t()) ::
  on_start()

Creates a new ETS table using the provided ets_opts.

These options are passed through as-is, with the exception of prepending the :public and :named_table options. Seeing as you can't execute inside the GenServers, your table will have to be public to be interacted with.

Options

You may provide a third parameter containing Eternal options:

:name - override the default naming scheme and use a custom name for this table. Remember to use this name when calling stop/1.
:quiet - by default, Eternal logs debug messages. Setting this to true will disable this logging.

Examples

iex> Cldr.Eternal.start_link(:table1, [], [quiet: true])

iex> Cldr.Eternal.start_link(:table2, [:compressed], [quiet: true])

iex> Cldr.Eternal.start_link(:table3, [], [quiet: true])

stop(table)

@spec stop(table :: table()) :: :ok

Terminates both servers in charge of a given ETS table.

Note: this will terminate your ETS table.

Examples

iex> Cldr.Eternal.stop(:my_table)
:ok