Nebulex.Event.CacheEntryEvent (Nebulex v3.1.0)

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A cache entry event.

Summary

Types

t()

Type for a cache entry event.

target()

Type for the event target.

type()

Event type.

Functions

__types__()

Returns the event types.

deleted(enum)

Creates a new deleted event.

expired(enum)

Creates a new expired event.

inserted(enum)

Creates a new inserted event.

new(enum)

Creates a new event.

updated(enum)

Creates a new updated event.

Types

t()

@type t() :: %Nebulex.Event.CacheEntryEvent{
  cache: Nebulex.Cache.t(),
  command: atom(),
  metadata: Nebulex.Event.metadata(),
  name: atom() | pid(),
  pid: pid() | nil,
  target: target(),
  type: type()
}

Type for a cache entry event.

The event will have the following keys:

  • :cache - The defined cache module.
  • :name - The cache name, or the cache PID when the cache was started without a name.
  • :pid - The cache PID.
  • :type - The event type.
  • :target - The event target: a key, a list of keys, or a query. See target/0.
  • :command - The cache command that emitted the event.
  • :metadata - The metadata given when the listener was registered. It also includes :extra_metadata with the per-command metadata passed through the :telemetry_metadata runtime option.

target()

@type target() :: {:key, key :: any()} | {:in, [key :: any()]} | {:q, query :: any()}

Type for the event target.

The event can target a single key, a list of keys, or a query.

  • A single key: {:key, key}. A command writing or deleting a single key will use this target. E.g., put, put_new, replace, delete, etc.
  • A list of keys: {:in, [key1, key2, ...]}. A command writing or deleting multiple keys will use this target. E.g., put_all, put_new_all, and delete_all.
  • A query: {:q, query}. A command deleting entries matching a query will use this target. E.g., delete_all.

type()

@type type() :: :deleted | :expired | :inserted | :updated

Event type.

  • :deleted - Emitted after an entry is deleted, or after a batch delete. The commands delete, take, and delete_all emit it. Note that delete emits it even when the key did not exist, since there is no way to know.
  • :expired - Emitted when a read finds the entry expired. The commands fetch, take, ttl, and has_key? emit it.
  • :inserted - Emitted after an entry is inserted, or after a batch insert. The commands put, put_new, put_all, and put_new_all emit it, as do incr and decr when they create the counter. Note that for put and put_all there is no way to know whether the entry existed before.
  • :updated - Emitted when an existing entry changes. The commands replace, expire, and touch emit it, as do incr and decr when the counter already exists.

Functions

__types__()

@spec __types__() :: [atom()]

Returns the event types.

Example

iex> Nebulex.Event.CacheEntryEvent.__types__()
[:deleted, :expired, :inserted, :updated]

deleted(enum)

@spec deleted(Enumerable.t()) :: t()

Creates a new deleted event.

expired(enum)

@spec expired(Enumerable.t()) :: t()

Creates a new expired event.

inserted(enum)

@spec inserted(Enumerable.t()) :: t()

Creates a new inserted event.

new(enum)

@spec new(Enumerable.t()) :: t()

Creates a new event.

Example

iex> Nebulex.Event.CacheEntryEvent.new(
...>   cache: MyApp.Cache,
...>   pid: self(),
...>   target: {:key, "foo"},
...>   command: :put,
...>   type: :inserted
...> )
%Nebulex.Event.CacheEntryEvent{
  cache: MyApp.Cache,
  command: :put,
  name: nil,
  pid: self(),
  type: :inserted,
  metadata: %{},
  target: {:key, "foo"}
}

updated(enum)

@spec updated(Enumerable.t()) :: t()

Creates a new updated event.