Class: CrudComponents::DynamicColumn

Inherits:
Object
  • Object
show all
Defined in:
lib/crud_components/dynamic_column.rb

Overview

A column whose data lives outside the model’s own table — a user-defined property kept in a separate store (definition + value tables, a JSONB blob, an external API). The model knows nothing about it; you build one per request from wherever your custom properties live and hand it to ‘crud_collection` via `extra_columns:`.

CrudComponents::DynamicColumn.new(:priority,
  label: 'Priority', as: :number,
  if:      -> { can?(:read, prop) },           # same gate as a field's if:
  preload: ->(records) {                       # batch-load once per page (no N+1)
    PropertyValue.where(definition: prop, subject: records).index_by(&:subject_id)
  },
  sort:   ->(scope, dir) { ... },              # optional — omit for display-only
  filter: ->(scope, value) { ... }) { |record, loaded| loaded[record.id]&.value }

The block is the value resolver: ‘|record|` or `|record, loaded|`, where `loaded` is whatever `preload:` returned. It returns a plain value that the `as:` renderer (or, with no `as:`, the value’s type) displays — exactly like a computed field. ‘filter:`/`sort:` are the same facet blocks the DSL takes; supply them only when the data is reachable in SQL, otherwise the column is display-only and never reaches the query layer.

A dynamic column often is a domain object (a mail, a resource), so its header can carry a link and its own bulk actions, rendered in the ‘<th>`:

CrudComponents::DynamicColumn.new(:mail_42,
  label:  'Welcome mail',
  header: -> { link_to mail.name, mail },             # HTML-safe String or a view-context block
  header_actions: [                                   # the same Action API as row/collection actions
    CrudComponents::Action.new(:send_all, icon: 'send', method: :post) { send_all_path(mail) },
    CrudComponents::Action.new(:unschedule_all, method: :post) { unschedule_all_path(mail) }
  ],
  preload: ->(records) { ... }) { |record, loaded| loaded[record.id] }

‘header:` replaces the plain `human_name` text (a String is rendered as-is —mark it `html_safe` if it carries markup; a block is `instance_exec`ed in the view, so it may call `link_to` and friends). `header_actions:` renders after the header; an `on: :selection` action acts on the ticked rows (it submits the shared select-form, so its path closes over the column’s object × the selection), while any other action renders as a plain link/button.

header:/header_actions: are not consumed here — they ride along in ‘options` and are read off the field by Fields::Base, exactly like a declared attribute’s ‘attribute :x, header_actions: […]`.

Constant Summary collapse

FACET_KEYS =

Keys consumed here; everything else (as:, if:, label:, header:, header_actions:, unit:, digits:, …) flows into ‘options` just like a declared attribute’s options.

%i[filter sort render].freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name, preload: nil, **opts, &value_block) ⇒ DynamicColumn

Returns a new instance of DynamicColumn.



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# File 'lib/crud_components/dynamic_column.rb', line 54

def initialize(name, preload: nil, **opts, &value_block)
  @name = name.to_sym
  @value_block = value_block
  @preload_block = preload
  @facets = opts.slice(*FACET_KEYS).compact
  @options = opts.except(*FACET_KEYS)
end

Instance Attribute Details

#facets ⇒ Object (readonly)

Returns the value of attribute facets.



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# File 'lib/crud_components/dynamic_column.rb', line 47

def facets
  @facets
end

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/crud_components/dynamic_column.rb', line 47

def name
  @name
end

#options ⇒ Object (readonly)

Returns the value of attribute options.



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# File 'lib/crud_components/dynamic_column.rb', line 47

def options
  @options
end

#preload_block ⇒ Object (readonly)

Returns the value of attribute preload_block.



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# File 'lib/crud_components/dynamic_column.rb', line 47

def preload_block
  @preload_block
end

#value_block ⇒ Object (readonly)

Returns the value of attribute value_block.



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# File 'lib/crud_components/dynamic_column.rb', line 47

def value_block
  @value_block
end

Instance Method Details

#to_field(model) ⇒ Object

A request-scoped field bound to ‘model`. Not memoized on the Structure, so it may carry the per-request value cache (see Fields::DynamicField).



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# File 'lib/crud_components/dynamic_column.rb', line 64

def to_field(model)
  Fields::DynamicField.new(self, model)
end