Class: McpToolkit::ListExecutor

Inherits:
Object
  • Object
show all
Defined in:
lib/mcp_toolkit/list_executor.rb

Overview

Runs a read-only, paginated "list" query for a registered resource, rooted on the scoped relation. Supports the standard ids, updated_since, limit, offset filters plus the resource's declared per-attribute filters (equality AND operator-based — see McpToolkit::Filtering), and serializes via the resource's serializer, producing the { <root> => [...], meta: {...} } wrapper. An optional fields param applies a sparse fieldset to each row (see McpToolkit::FieldSelection).

Constant Summary collapse

DEFAULT_LIMIT = 
25
MAX_LIMIT = 
100
NUMERIC_PK_TYPES =

Column types whose primary key sorts naturally by id. Anything else (e.g. a string/uuid PK) sorts by created_at instead.

%i[integer bigint].freeze

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(resource:, scope_root:, params:) ⇒ ListExecutor

Returns a new instance of ListExecutor.



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# File 'lib/mcp_toolkit/list_executor.rb', line 21

def initialize(resource:, scope_root:, params:)
  @resource = resource
  @scope_root = scope_root
  @params = (params || {}).deep_symbolize_keys
end

Class Method Details

.call(resource:, scope_root:, params:) ⇒ Object 



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# File 'lib/mcp_toolkit/list_executor.rb', line 17

def self.call(resource:, scope_root:, params:)
  new(resource:, scope_root:, params:).call
end

Instance Method Details

#call ⇒ Object 



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# File 'lib/mcp_toolkit/list_executor.rb', line 27

def call
  # Validate the sparse fieldset BEFORE running the query so a bad `fields`
  # fails fast rather than after a needless count + fetch.
  selection = McpToolkit::FieldSelection.build(resource:, raw: params[:fields])
  relation = build_relation
  total_count = relation.count
  rows = paginate(relation).to_a

  McpToolkit::Serialization.new(resource.serializer, selection).collection(
    rows, scope: scope_root, total_count:, limit:, offset:
  )
end