Class: CMDx::Stores::Memory

Inherits:
Object
  • Object
show all
Defined in:
lib/cmdx/stores/memory.rb

Overview

Process-local key/value store with optional per-key TTL. Thread-safe via an internal mutex. Suitable for tests and single-process dev; not shared across workers.

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Memory

Returns a new instance of Memory.



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# File 'lib/cmdx/stores/memory.rb', line 10

def initialize
  @mutex = Mutex.new
  @entries = {}
end

Instance Method Details

#decr(key, ttl: nil) ⇒ Integer

Returns value after decrement (floors at 0, removing the key).

Parameters:

  • key (String, Symbol)

Returns:

  • (Integer) —

    value after decrement (floors at 0, removing the key)

Raises:

  • (ArgumentError) —

    when ttl is invalid (only when ttl is passed)



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# File 'lib/cmdx/stores/memory.rb', line 98

def decr(key, ttl: nil)
  key = Stores.key!(key)
  Stores.ttl!(ttl) if ttl

  @mutex.synchronize do
    entry = @entries[key]
    if entry && expired?(entry)
      @entries.delete(key)
      entry = nil
    end

    count = entry ? entry[:value].to_i : 0
    count = count.positive? ? count - 1 : 0
    expires_at = entry&.fetch(:expires_at, nil)

    if count.zero?
      @entries.delete(key)
    else
      @entries[key] = { value: count.to_s, expires_at: }
    end

    count
  end
end

#del(key) ⇒ Integer

Returns 1 when a key was removed, 0 otherwise.

Parameters:

  • key (String, Symbol)

Returns:

  • (Integer) —

    1 when a key was removed, 0 otherwise



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# File 'lib/cmdx/stores/memory.rb', line 125

def del(key)
  key = Stores.key!(key)

  @mutex.synchronize do
    @entries.delete(key) ? 1 : 0
  end
end

#del_if(key, expected) ⇒ Boolean

Returns whether the key was removed.

Parameters:

  • key (String, Symbol)
  • expected (#to_s)

Returns:

  • (Boolean) —

    whether the key was removed



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# File 'lib/cmdx/stores/memory.rb', line 136

def del_if(key, expected)
  key = Stores.key!(key)

  @mutex.synchronize do
    entry = @entries[key]
    return false unless entry && !expired?(entry)
    return false unless entry[:value] == expected.to_s

    @entries.delete(key)
    true
  end
end

#get(key) ⇒ String?

Returns stored value, or nil when missing or expired.

Parameters:

  • key (String, Symbol)

Returns:

  • (String, nil) —

    stored value, or nil when missing or expired



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# File 'lib/cmdx/stores/memory.rb', line 17

def get(key)
  key = Stores.key!(key)

  @mutex.synchronize do
    entry = @entries[key]
    return unless entry
    return if expired?(entry)

    entry[:value]
  end
end

#incr(key, ttl: nil) ⇒ Integer

Returns value after increment.

Parameters:

  • key (String, Symbol)
  • ttl (Integer, nil) (defaults to: nil) —

    when set, refreshes expiry on every increment

Returns:

  • (Integer) —

    value after increment

Raises:

  • (ArgumentError) —

    when ttl is invalid



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# File 'lib/cmdx/stores/memory.rb', line 58

def incr(key, ttl: nil)
  key = Stores.key!(key)
  ttl = Stores.ttl!(ttl) if ttl

  @mutex.synchronize do
    entry = @entries[key]
    if entry && expired?(entry)
      @entries.delete(key)
      entry = nil
    end

    count = entry ? entry[:value].to_i + 1 : 1
    expires_at = (Util.monotonic_now + ttl if ttl)

    @entries[key] = { value: count.to_s, expires_at: }
    count
  end
end

#set(key, value, ttl: nil, nx: false, xx: false) ⇒ Boolean

Returns whether the value was written.

Parameters:

  • key (String, Symbol)
  • value (#to_s)
  • ttl (Integer, nil) (defaults to: nil) —

    seconds until expiry (nil = no expiry)

  • nx (Boolean) (defaults to: false) —

    set only when the key is absent

  • xx (Boolean) (defaults to: false) —

    set only when the key is present

Returns:

  • (Boolean) —

    whether the value was written

Raises:

  • (ArgumentError) —

    when nx and xx are both true, or ttl is invalid



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# File 'lib/cmdx/stores/memory.rb', line 36

def set(key, value, ttl: nil, nx: false, xx: false)
  key = Stores.key!(key)
  ttl = Stores.ttl!(ttl) if ttl
  Stores.nx_xx!(nx, xx)

  expires_at = ttl ? Util.monotonic_now + ttl : nil
  @mutex.synchronize do
    entry = @entries[key]
    present = entry && !expired?(entry)

    return false if nx && present
    return false if xx && !present

    @entries[key] = { value: value.to_s, expires_at: }
    true
  end
end

#ttl(key) ⇒ Integer?

Returns whole seconds until expiry, or nil when missing or expired.

Parameters:

  • key (String, Symbol)

Returns:

  • (Integer, nil) —

    whole seconds until expiry, or nil when missing or expired



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# File 'lib/cmdx/stores/memory.rb', line 79

def ttl(key)
  key = Stores.key!(key)

  @mutex.synchronize do
    entry = @entries[key]
    return unless entry
    return if expired?(entry)

    expires_at = entry[:expires_at]
    return unless expires_at

    remaining = expires_at - Util.monotonic_now
    remaining.positive? ? remaining.ceil : nil
  end
end