Module: Familia::Horreum::ManagementMethods

Includes:
RelatedFieldsManagement
Defined in:
lib/familia/horreum/subclass/management.rb

Overview

ManagementMethods: Provides class-level functionality for Horreum records.

This module is extended into classes that include Familia::Horreum, providing methods for Database operations and object management.

Key features:

  • Includes RelatedFieldsManagement for DataType field handling
  • Provides utility methods for working with Database objects

Instance Method Summary collapse

Methods included from RelatedFieldsManagement

#attach_class_related_field, #attach_instance_related_field

Instance Method Details

#all(suffix = nil) ⇒ Object



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# File 'lib/familia/horreum/subclass/management.rb', line 245

def all(suffix = nil)
  suffix ||= self.suffix
  # objects that could not be parsed will be nil
  keys(suffix).filter_map { |k| find_by_key(k) }
end

#any?(filter = '*') ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/familia/horreum/subclass/management.rb', line 251

def any?(filter = '*')
  matching_keys_count(filter) > 0
end

#createObject

Note:

The behavior of this method depends on the implementation of #new, #exists?, and #save in the class and its superclasses.

Creates and persists a new instance of the class.

This method serves as a factory method for creating and persisting new instances of the class. It combines object instantiation, existence checking, and persistence in a single operation.

The method is flexible in accepting both positional and keyword arguments: - Positional arguments (*args) are passed directly to the constructor. - Keyword arguments (**kwargs) are passed as a hash to the constructor.

After instantiation, the method checks if an object with the same identifier already exists. If it does, a Familia::Problem exception is raised to prevent overwriting existing data.

Finally, the method saves the new instance returns it.

Examples:

Creating an object with keyword arguments

User.create(name: "John", age: 30)

Creating an object with positional and keyword arguments (not recommended)

Product.create("SKU123", name: "Widget", price: 9.99)

Parameters:

  • *args (Array)

    Variable number of positional arguments to be passed to the constructor.

  • **kwargs (Hash)

    Keyword arguments to be passed to the constructor.

Returns:

  • (Object)

    The newly created and persisted instance.

Raises:

  • (Familia::Problem)

    If an instance with the same identifier already exists.

See Also:



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# File 'lib/familia/horreum/subclass/management.rb', line 56

def create(*, **)
  fobj = new(*, **)
  fobj.save_if_not_exists
  fobj
end

#dbkey(identifier, suffix = self.suffix) ⇒ Object

+identifier+ can be a value or an Array of values used to create the index. We don’t enforce a default suffix; that’s left up to the instance. The suffix is used to differentiate between different types of objects.

+suffix+ If a nil value is explicitly passed in, it won’t appear in the redis key that’s returned. If no suffix is passed in, the class’ suffix is used as the default (via the class method self.suffix). It’s an important distinction b/c passing in an explicitly nil is how DataType objects at the class level are created without the global default ‘object’ suffix. See DataType#dbkey “parent_class?” for more details.



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# File 'lib/familia/horreum/subclass/management.rb', line 236

def dbkey(identifier, suffix = self.suffix)
  if identifier.to_s.empty?
    raise NoIdentifier, "#{self} requires non-empty identifier, got: #{identifier.inspect}"
  end

  identifier &&= identifier.to_s
  Familia.dbkey(prefix, identifier, suffix)
end

#destroy!(identifier, suffix = nil) ⇒ Boolean

Destroys an object in Database with the given identifier.

This method is part of Familia’s high-level object lifecycle management. While delete! operates directly on dbkeys, destroy! operates at the object level and is used for ORM-style operations. Use destroy! when removing complete objects from the system, and delete! when working directly with dbkeys.

Examples:

User.destroy!(123)  # Removes user:123:object from Redis

Parameters:

  • identifier (String, Integer)

    The unique identifier for the object to destroy.

  • suffix (Symbol, nil) (defaults to: nil)

    The suffix to use in the dbkey (default: class suffix).

Returns:

  • (Boolean)

    true if the object was successfully destroyed, false otherwise.



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# File 'lib/familia/horreum/subclass/management.rb', line 198

def destroy!(identifier, suffix = nil)
  suffix ||= self.suffix
  return false if identifier.to_s.empty?

  objkey = dbkey identifier, suffix

  ret = dbclient.del objkey
  Familia.trace :DESTROY!, dbclient, "#{objkey} #{ret.inspect}", caller(1..1) if Familia.debug?
  ret.positive?
end

#exists?(identifier, suffix = nil) ⇒ Boolean

Checks if an object with the given identifier exists in Redis.

This method constructs the full dbkey using the provided identifier and suffix, then checks if the key exists in Redis.

Examples:

User.exists?(123)  # Returns true if user:123:object exists in Redis

Parameters:

  • identifier (String, Integer)

    The unique identifier for the object.

  • suffix (Symbol, nil) (defaults to: nil)

    The suffix to use in the dbkey (default: class suffix).

Returns:

  • (Boolean)

    true if the object exists, false otherwise.

Raises:



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# File 'lib/familia/horreum/subclass/management.rb', line 172

def exists?(identifier, suffix = nil)
  raise NoIdentifier, "Empty identifier" if identifier.to_s.empty?
  suffix ||= self.suffix

  objkey = dbkey identifier, suffix

  ret = dbclient.exists objkey
  Familia.trace :EXISTS, dbclient, "#{objkey} #{ret.inspect}", caller(1..1) if Familia.debug?

  ret.positive? # differs from Valkey API but I think it's okay bc `exists?` is a predicate method.
end

#find_by_id(identifier, suffix = nil) ⇒ Object? Also known as: find, load, from_identifier

Retrieves and instantiates an object from Database using its identifier.

This method constructs the full dbkey using the provided identifier and suffix, then delegates to find_by_key for the actual retrieval and instantiation.

It’s a higher-level method that abstracts away the key construction, making it easier to retrieve objects when you only have their identifier.

Examples:

User.find_by_id(123)  # Equivalent to User.find_by_key("user:123:object")

Parameters:

  • identifier (String, Integer)

    The unique identifier for the object.

  • suffix (Symbol) (defaults to: nil)

    The suffix to use in the dbkey (default: :object).

Returns:

  • (Object, nil)

    An instance of the class if found, nil otherwise.



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# File 'lib/familia/horreum/subclass/management.rb', line 146

def find_by_id(identifier, suffix = nil)
  suffix ||= self.suffix
  return nil if identifier.to_s.empty?

  objkey = dbkey(identifier, suffix)

  Familia.ld "[.find_by_id] #{self} from key #{objkey})"
  Familia.trace :FIND_BY_ID, Familia.dbclient(uri), objkey, caller(1..1).first if Familia.debug?
  find_by_key objkey
end

#find_by_key(objkey) ⇒ Object? Also known as: from_dbkey

Retrieves and instantiates an object from Database using the full object key.

This method performs a two-step process to safely retrieve and instantiate objects:

  1. It first checks if the key exists in Redis. This is crucial because:
    • It provides a definitive answer about the object’s existence.
    • It prevents ambiguity that could arise from hgetall returning an empty hash for non-existent keys, which could lead to the creation of “empty” objects.
  2. If the key exists, it retrieves the object’s data and instantiates it.

This approach ensures that we only attempt to instantiate objects that actually exist in Redis, improving reliability and simplifying debugging.

Examples:

User.find_by_key("user:123")  # Returns a User instance if it exists,
nil otherwise

Parameters:

  • objkey (String)

    The full dbkey for the object.

Returns:

  • (Object, nil)

    An instance of the class if the key exists, nil otherwise.

Raises:

  • (ArgumentError)

    If the provided key is empty.



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# File 'lib/familia/horreum/subclass/management.rb', line 103

def find_by_key(objkey)
  raise ArgumentError, 'Empty key' if objkey.to_s.empty?

  # We use a lower-level method here b/c we're working with the
  # full key and not just the identifier.
  does_exist = dbclient.exists(objkey).positive?

  Familia.ld "[.find_by_key] #{self} from key #{objkey} (exists: #{does_exist})"
  Familia.trace :FROM_KEY, dbclient, objkey, caller(1..1) if Familia.debug?

  # This is the reason for calling exists first. We want to definitively
  # and without any ambiguity know if the object exists in Redis. If it
  # doesn't, we return nil. If it does, we proceed to load the object.
  # Otherwise, hgetall will return an empty hash, which will be passed to
  # the constructor, which will then be annoying to debug.
  return unless does_exist

  obj = dbclient.hgetall(objkey) # horreum objects are persisted as database hashes
  Familia.trace :FROM_KEY2, dbclient, "#{objkey}: #{obj.inspect}", caller(1..1) if Familia.debug?

  new(**obj)
end

#find_keys(suffix = '*') ⇒ Array<String>

Finds all keys in Database matching the given suffix pattern.

This method searches for all dbkeys that match the given suffix pattern. It uses the class’s dbkey method to construct the search pattern.

Examples:

User.find  # Returns all keys matching user:*:object
User.find('active')  # Returns all keys matching user:*:active

Parameters:

  • suffix (String) (defaults to: '*')

    The suffix pattern to match (default: ‘*’).

Returns:

  • (Array<String>)

    An array of matching dbkeys.



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# File 'lib/familia/horreum/subclass/management.rb', line 221

def find_keys(suffix = '*')
  dbclient.keys(dbkey('*', suffix)) || []
end

#matching_keys_count(filter = '*') ⇒ Integer Also known as: size

Returns the number of dbkeys matching the given filter pattern

Parameters:

  • filter (String) (defaults to: '*')

    dbkey pattern to match (default: ‘*’)

Returns:

  • (Integer)

    Number of matching keys



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# File 'lib/familia/horreum/subclass/management.rb', line 259

def matching_keys_count(filter = '*')
  dbclient.keys(dbkey(filter)).compact.size
end

#multiget(*ids) ⇒ Object



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# File 'lib/familia/horreum/subclass/management.rb', line 62

def multiget(*ids)
  ids = rawmultiget(*ids)
  ids.filter_map { |json| from_json(json) }
end

#rawmultiget(*ids) ⇒ Object



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# File 'lib/familia/horreum/subclass/management.rb', line 67

def rawmultiget(*ids)
  ids.collect! { |objid| dbkey(objid) }
  return [] if ids.compact.empty?

  Familia.trace :MULTIGET, dbclient, "#{ids.size}: #{ids}", caller(1..1) if Familia.debug?
  dbclient.mget(*ids)
end