defmodule AshPostgres.Join do @moduledoc false import Ecto.Query, only: [from: 2, subquery: 1] alias Ash.Query.{BooleanExpression, Not, Ref} @known_inner_join_operators [ Eq, GreaterThan, GreaterThanOrEqual, In, LessThanOrEqual, LessThan, NotEq ] |> Enum.map(&Module.concat(Ash.Query.Operator, &1)) @known_inner_join_functions [ Ago, Contains ] |> Enum.map(&Module.concat(Ash.Query.Function, &1)) @known_inner_join_predicates @known_inner_join_functions ++ @known_inner_join_operators def join_all_relationships( query, filter, opts \\ [], relationship_paths \\ nil, path \\ [], source \\ nil, sort? \\ true, join_filters \\ nil, parent_bindings \\ nil ) # simple optimization for common cases def join_all_relationships( query, filter, _opts, relationship_paths, _path, _source, _sort?, _join_filters, _parent_bindings ) when is_nil(relationship_paths) and filter in [nil, true, false] do {:ok, query} end def join_all_relationships( query, filter, opts, relationship_paths, path, source, sort?, join_filters, parent_query ) do relationship_paths = cond do relationship_paths -> relationship_paths opts[:no_this?] -> filter |> Ash.Filter.map(fn %Ash.Query.Parent{} -> nil other -> other end) |> Ash.Filter.relationship_paths() |> to_joins(filter, query.__ash_bindings__.resource) true -> filter |> Ash.Filter.relationship_paths() |> to_joins(filter, query.__ash_bindings__.resource) end Enum.reduce_while(relationship_paths, {:ok, query}, fn {_join_type, []}, {:ok, query} -> {:cont, {:ok, query}} {join_type, [relationship | rest_rels]}, {:ok, query} -> source = source || relationship.source current_path = path ++ [relationship] current_join_type = join_type look_for_join_types = case join_type do :left -> [:left, :inner] :inner -> [:left, :inner] other -> [other] end binding = get_binding(source, Enum.map(current_path, & &1.name), query, look_for_join_types) # We can't reuse joins if we're adding filters/have a separate parent binding if is_nil(join_filters) && is_nil(parent_query) && binding do case join_all_relationships( query, filter, opts, [{join_type, rest_rels}], current_path, source, sort? ) do {:ok, query} -> {:cont, {:ok, query}} {:error, error} -> {:halt, {:error, error}} end else case join_relationship( set_parent_bindings(query, parent_query), relationship, Enum.map(path, & &1.name), current_join_type, source, filter, sort?, Ash.Filter.move_to_relationship_path( join_filters[Enum.map(current_path, & &1.name)], [relationship.name] ) ) do {:ok, joined_query} -> joined_query_with_distinct = add_distinct(relationship, join_type, joined_query) case join_all_relationships( joined_query_with_distinct, filter, opts, [{join_type, rest_rels}], current_path, source, sort?, join_filters, joined_query ) do {:ok, query} -> {:cont, {:ok, query}} {:error, error} -> {:halt, {:error, error}} end {:error, error} -> {:halt, {:error, error}} end end end) end defp set_parent_bindings(query, parent_query) do if parent_query do AshPostgres.Expr.set_parent_path(query, parent_query, false) else query end end defp to_joins(paths, filter, resource) do paths |> Enum.reject(&(&1 == [])) |> Enum.map(fn path -> if can_inner_join?(path, filter) do {:inner, AshPostgres.Join.relationship_path_to_relationships( resource, path )} else {:left, AshPostgres.Join.relationship_path_to_relationships( resource, path )} end end) end def relationship_path_to_relationships(resource, path, acc \\ []) def relationship_path_to_relationships(_resource, [], acc), do: Enum.reverse(acc) def relationship_path_to_relationships(resource, [name | rest], acc) do relationship = Ash.Resource.Info.relationship(resource, name) if !relationship do raise "no such relationship #{inspect(resource)}.#{name}" end relationship_path_to_relationships(relationship.destination, rest, [relationship | acc]) end def maybe_get_resource_query( resource, relationship, root_query, sort?, path \\ [], bindings \\ nil, start_binding \\ nil, is_subquery? \\ true, join_relationships? \\ false ) do read_action = relationship.read_action || Ash.Resource.Info.primary_action!(relationship.destination, :read).name context = (bindings || root_query.__ash_bindings__).context resource |> Ash.Query.new(nil, base_filter?: false) |> Ash.Query.set_context(%{data_layer: %{start_bindings_at: start_binding}}) |> Ash.Query.set_context(context) |> Ash.Query.set_context(relationship.context) |> Ash.Query.for_read(read_action, %{}, actor: context[:private][:actor], tenant: context[:private][:tenant] ) |> Ash.Query.unset([:sort, :distinct, :select, :limit, :offset]) |> case do %{valid?: true} = query -> ash_query = query initial_query = %{ AshPostgres.DataLayer.resource_to_query(resource, nil) | prefix: Map.get(root_query, :prefix) } initial_query = do_relationship_sort(initial_query, relationship, sort?) case Ash.Query.data_layer_query(query, initial_query: initial_query ) do {:ok, query} -> query = if join_relationships? do {:ok, related_filter} = Ash.Filter.hydrate_refs( relationship.filter, %{ resource: relationship.destination, public?: false } ) {:ok, query} = AshPostgres.Join.join_all_relationships(query, related_filter) query else query end {query, acc} = query |> do_base_filter( root_query, ash_query, resource, path, bindings, root_query.__ash_bindings__.expression_accumulator ) |> do_relationship_filter( relationship, root_query, ash_query, resource, path, bindings, is_subquery? ) query = if Enum.empty?(List.wrap(query.order_bys)) && Enum.empty?(query.joins) do query else from(row in subquery(query), []) |> AshPostgres.DataLayer.default_bindings(relationship.destination) |> AshPostgres.DataLayer.merge_expr_accumulator( query.__ash_bindings__.expression_accumulator ) |> Map.update!( :__ash_bindings__, &Map.put(&1, :current, query.__ash_bindings__.current) ) end {:ok, Map.put(query, :__tenant__, Map.get(root_query, :__tenant__)), acc} {:error, error} -> {:error, error} end query -> {:error, query} end |> case do {:ok, query, acc} -> if Enum.empty?(query.joins) || is_subquery? do {:ok, query, acc} else {:ok, from(row in subquery(query), []) |> Map.put(:__ash_bindings__, query.__ash_bindings__), acc} end {:error, error} -> {:error, error} end end defp do_relationship_sort( query, %{destination: destination, sort: sort, from_many?: true}, true ) when sort not in [nil, []] do query = AshPostgres.DataLayer.default_bindings(query, destination) {:ok, order_by, query} = AshPostgres.Sort.sort(query, sort, query.__ash_bindings__.resource, [], 0, :return) from(row in query, order_by: ^order_by) end defp do_relationship_sort(query, _, _), do: query defp do_relationship_filter({query, acc}, %{filter: nil}, _, _, _, _, _, _), do: {query, acc} defp do_relationship_filter( {query, acc}, relationship, root_query, ash_query, resource, path, bindings, is_subquery? ) do filter = resource |> Ash.Filter.parse!( relationship.filter, ash_query.aggregates, ash_query.calculations, Map.update( ash_query.context, :parent_stack, [relationship.source], &[&1 | relationship.source] ) ) base_bindings = bindings || query.__ash_bindings__ parent_binding = case :lists.droplast(path) do [] -> base_bindings.bindings |> Enum.find_value(fn {key, %{type: type}} -> if type == :root do key end end) path -> get_binding( root_query.__ash_bindings__.resource, path, %{query | __ash_bindings__: base_bindings}, [ :inner, :left ] ) end parent_bindings = %{ base_bindings | resource: relationship.source, calculations: %{}, parent_resources: [], aggregate_defs: %{}, context: relationship.context, current: parent_binding + 1 } parent_bindings = if bindings do Map.put(parent_bindings, :parent_is_parent_as?, !is_subquery?) else parent_bindings |> Map.update!(:bindings, &Map.take(&1, [parent_binding])) end has_bindings? = not is_nil(bindings) bindings = base_bindings |> Map.put(:parent_bindings, parent_bindings) |> Map.put(:parent_resources, [ relationship.source | parent_bindings[:parent_resources] || [] ]) {dynamic, acc} = if has_bindings? do filter = if is_subquery? do Ash.Filter.move_to_relationship_path(filter, path) else filter end AshPostgres.Expr.dynamic_expr(root_query, filter, bindings, true, acc) else AshPostgres.Expr.dynamic_expr(query, filter, bindings, true, acc) end {from(row in query, where: ^dynamic), acc} end defp do_base_filter(query, root_query, ash_query, resource, path, bindings, acc) do case Ash.Resource.Info.base_filter(resource) do nil -> {query, %AshPostgres.Expr.ExprInfo{}} filter -> filter = resource |> Ash.Filter.parse!( filter, ash_query.aggregates, ash_query.calculations, ash_query.context ) {dynamic, acc} = if bindings do filter = Ash.Filter.move_to_relationship_path(filter, path) AshPostgres.Expr.dynamic_expr(root_query, filter, bindings, true, acc) else AshPostgres.Expr.dynamic_expr(query, filter, query.__ash_bindings__, true, acc) end {from(row in query, where: ^dynamic), acc} end end def set_join_prefix(join_query, query, resource) do if Ash.Resource.Info.multitenancy_strategy(resource) == :context do %{ join_query | prefix: query.prefix || AshPostgres.DataLayer.Info.schema(resource) || "public" } else %{ join_query | prefix: AshPostgres.DataLayer.Info.schema(resource) || AshPostgres.DataLayer.Info.repo(resource, :mutate).config()[:default_prefix] || "public" } end end defp can_inner_join?(path, expr, seen_an_or? \\ false) defp can_inner_join?(path, %{expression: expr}, seen_an_or?), do: can_inner_join?(path, expr, seen_an_or?) defp can_inner_join?(_path, expr, _seen_an_or?) when expr in [nil, true, false], do: true defp can_inner_join?(path, %BooleanExpression{op: :and, left: left, right: right}, seen_an_or?) do can_inner_join?(path, left, seen_an_or?) || can_inner_join?(path, right, seen_an_or?) end defp can_inner_join?(path, %BooleanExpression{op: :or, left: left, right: right}, _) do can_inner_join?(path, left, true) && can_inner_join?(path, right, true) end defp can_inner_join?( _, %Not{}, _ ) do false end defp can_inner_join?( search_path, %struct{__operator__?: true, left: %Ref{relationship_path: relationship_path}}, seen_an_or? ) when search_path == relationship_path and struct in @known_inner_join_predicates do not seen_an_or? end defp can_inner_join?( search_path, %struct{__operator__?: true, right: %Ref{relationship_path: relationship_path}}, seen_an_or? ) when search_path == relationship_path and struct in @known_inner_join_predicates do not seen_an_or? end defp can_inner_join?( search_path, %struct{__function__?: true, arguments: arguments}, seen_an_or? ) when struct in @known_inner_join_predicates do if Enum.any?(arguments, &match?(%Ref{relationship_path: ^search_path}, &1)) do not seen_an_or? else true end end defp can_inner_join?(_, _, _), do: false @doc false def get_binding(resource, candidate_path, %{__ash_bindings__: _} = query, types) do types = List.wrap(types) Enum.find_value(query.__ash_bindings__.bindings, fn {binding, %{path: path, source: source, type: type}} -> if type in types && Ash.SatSolver.synonymous_relationship_paths?(resource, path, candidate_path, source) do binding end _ -> nil end) end def get_binding(_, _, _, _), do: nil defp add_distinct(relationship, _join_type, joined_query) do if !joined_query.__ash_bindings__.in_group? && (relationship.cardinality == :many || Map.get(relationship, :from_many?)) && !joined_query.distinct do from(row in joined_query, distinct: ^Ash.Resource.Info.primary_key(joined_query.__ash_bindings__.resource) ) else joined_query end end defp join_relationship( query, %{manual: {module, opts}} = relationship, path, kind, source, filter, sort?, apply_filter ) do full_path = path ++ [relationship.name] initial_ash_bindings = query.__ash_bindings__ binding_data = %{type: kind, path: full_path, source: source} query = AshPostgres.DataLayer.add_binding(query, binding_data) used_aggregates = Ash.Filter.used_aggregates(filter, full_path) use_root_query_bindings? = Enum.empty?(used_aggregates) root_bindings = if use_root_query_bindings? do query.__ash_bindings__ end with {:ok, relationship_destination, acc} <- maybe_get_resource_query( relationship.destination, relationship, query, sort?, full_path, root_bindings ) do {relationship_destination, acc} = relationship_destination |> Ecto.Queryable.to_query() |> set_join_prefix(query, relationship.destination) |> maybe_apply_filter(query, root_bindings, apply_filter, acc) query = AshPostgres.DataLayer.merge_expr_accumulator(query, acc) binding_kinds = case kind do :left -> [:left, :inner] :inner -> [:left, :inner] other -> [other] end current_binding = Enum.find_value(initial_ash_bindings.bindings, 0, fn {binding, data} -> if data.type in binding_kinds && data.path == path do binding end end) needs_subquery? = used_aggregates != [] || Map.get(relationship, :from_many?) relationship_destination = if needs_subquery? do subquery(from(row in relationship_destination, limit: 1)) else relationship_destination end case module.ash_postgres_join( query, opts, current_binding, initial_ash_bindings.current, kind, relationship_destination ) do {:ok, query} -> AshPostgres.Aggregate.add_aggregates( query, used_aggregates, relationship.destination, false, initial_ash_bindings.current, {query.__ash_bindings__.resource, full_path} ) end end rescue e in UndefinedFunctionError -> if e.function == :ash_postgres_join do reraise """ Cannot join to a manual relationship #{inspect(module)} that does not implement the `AshPostgres.ManualRelationship` behaviour. """, __STACKTRACE__ else reraise e, __STACKTRACE__ end end defp join_relationship( query, %{type: :many_to_many} = relationship, path, kind, source, filter, sort?, apply_filter ) do join_relationship = Ash.Resource.Info.relationship(relationship.source, relationship.join_relationship) join_path = path ++ [join_relationship.name] full_path = path ++ [relationship.name] initial_ash_bindings = query.__ash_bindings__ binding_data = %{type: kind, path: full_path, source: source} query = query |> AshPostgres.DataLayer.add_binding(%{ path: join_path, type: :left, source: source }) |> AshPostgres.DataLayer.add_binding(binding_data) {:ok, related_filter} = Ash.Filter.hydrate_refs( relationship.filter, %{ resource: relationship.destination, aggregates: %{}, calculations: %{}, public?: false } ) related_filter = Ash.Filter.move_to_relationship_path(related_filter, full_path) {:ok, query} = join_all_relationships(query, related_filter) used_aggregates = Ash.Filter.used_aggregates(filter, full_path) use_root_query_bindings? = Enum.empty?(used_aggregates) root_bindings = if use_root_query_bindings? do query.__ash_bindings__ end with {:ok, relationship_through, through_acc} <- maybe_get_resource_query( relationship.through, join_relationship, query, false, join_path, root_bindings ), {:ok, relationship_destination, dest_acc} <- maybe_get_resource_query( relationship.destination, relationship, query, sort?, path, root_bindings ) do relationship_through = relationship_through |> Ecto.Queryable.to_query() |> set_join_prefix(query, relationship.through) {relationship_destination, dest_acc} = relationship_destination |> Ecto.Queryable.to_query() |> set_join_prefix(query, relationship.destination) |> maybe_apply_filter(query, root_bindings, apply_filter, dest_acc) query = query |> AshPostgres.DataLayer.merge_expr_accumulator(through_acc) |> AshPostgres.DataLayer.merge_expr_accumulator(dest_acc) binding_kinds = case kind do :left -> [:left, :inner] :inner -> [:left, :inner] other -> [other] end current_binding = Enum.find_value(initial_ash_bindings.bindings, 0, fn {binding, data} -> if data.type in binding_kinds && data.path == path do binding end end) needs_subquery? = used_aggregates != [] || Map.get(relationship, :from_many?) relationship_destination = if needs_subquery? do subquery(from(row in relationship_destination, limit: 1)) else relationship_destination end query = case kind do :inner -> from([{row, current_binding}] in query, join: through in ^relationship_through, as: ^initial_ash_bindings.current, on: field(row, ^relationship.source_attribute) == field(through, ^relationship.source_attribute_on_join_resource), join: destination in ^relationship_destination, as: ^(initial_ash_bindings.current + 1), on: field(destination, ^relationship.destination_attribute) == field(through, ^relationship.destination_attribute_on_join_resource) ) _ -> from([{row, current_binding}] in query, left_join: through in ^relationship_through, as: ^initial_ash_bindings.current, on: field(row, ^relationship.source_attribute) == field(through, ^relationship.source_attribute_on_join_resource), left_join: destination in ^relationship_destination, as: ^(initial_ash_bindings.current + 1), on: field(destination, ^relationship.destination_attribute) == field(through, ^relationship.destination_attribute_on_join_resource) ) end AshPostgres.Aggregate.add_aggregates( query, used_aggregates, relationship.destination, false, initial_ash_bindings.current, {query.__ash_bindings__.resource, full_path} ) end end defp join_relationship( query, relationship, path, kind, source, filter, sort?, apply_filter ) do full_path = path ++ [relationship.name] initial_ash_bindings = query.__ash_bindings__ binding_data = %{type: kind, path: full_path, source: source} query = AshPostgres.DataLayer.add_binding(query, binding_data) {:ok, related_filter} = Ash.Filter.hydrate_refs( relationship.filter, %{ resource: relationship.destination, public?: false } ) related_filter = Ash.Filter.move_to_relationship_path(related_filter, full_path) {:ok, query} = join_all_relationships(query, related_filter) used_aggregates = Ash.Filter.used_aggregates(filter, full_path) use_root_query_bindings? = Enum.empty?(used_aggregates) needs_subquery? = Map.get(relationship, :from_many?, false) root_bindings = if use_root_query_bindings? && !needs_subquery? do query.__ash_bindings__ end case maybe_get_resource_query( relationship.destination, relationship, query, sort?, full_path, root_bindings, nil, use_root_query_bindings? && !needs_subquery? ) do {:error, error} -> {:error, error} {:ok, relationship_destination, acc} -> {relationship_destination, acc} = relationship_destination |> Ecto.Queryable.to_query() |> set_join_prefix(query, relationship.destination) |> maybe_apply_filter(query, root_bindings, apply_filter, acc) query = AshPostgres.DataLayer.merge_expr_accumulator(query, acc) relationship_destination = if needs_subquery? do subquery(from(row in relationship_destination, limit: 1)) else relationship_destination end binding_kinds = case kind do :left -> [:left, :inner] :inner -> [:left, :inner] other -> [other] end current_binding = Enum.find_value(initial_ash_bindings.bindings, 0, fn {binding, data} -> if data.type in binding_kinds && data.path == path do binding end end) relationship_destination = used_aggregates |> Enum.reject(fn aggregate -> AshPostgres.Aggregate.optimizable_first_aggregate?( relationship.destination, aggregate ) end) |> case do [] -> relationship_destination _ -> subquery(relationship_destination) end query = case {kind, Map.get(relationship, :no_attributes?, false), needs_subquery?} do {:inner, true, false} -> from([{row, current_binding}] in query, join: destination in ^relationship_destination, as: ^initial_ash_bindings.current, on: true ) {:inner, true, true} -> from([{row, current_binding}] in query, inner_lateral_join: destination in ^relationship_destination, as: ^initial_ash_bindings.current, on: true ) {:inner, false, false} -> from([{row, current_binding}] in query, join: destination in ^relationship_destination, as: ^initial_ash_bindings.current, on: field(row, ^relationship.source_attribute) == field( destination, ^relationship.destination_attribute ) ) {:inner, false, true} -> from([{row, current_binding}] in query, inner_lateral_join: destination in ^relationship_destination, as: ^initial_ash_bindings.current, on: field(row, ^relationship.source_attribute) == field( destination, ^relationship.destination_attribute ) ) {:left, true, false} -> from([{row, current_binding}] in query, left_join: destination in ^relationship_destination, as: ^initial_ash_bindings.current, on: true ) {:left, true, true} -> from([{row, current_binding}] in query, left_lateral_join: destination in ^relationship_destination, as: ^initial_ash_bindings.current, on: true ) {:left, false, false} -> from([{row, current_binding}] in query, left_join: destination in ^relationship_destination, as: ^initial_ash_bindings.current, on: field(row, ^relationship.source_attribute) == field( destination, ^relationship.destination_attribute ) ) {:left, false, true} -> from([{row, current_binding}] in query, left_lateral_join: destination in ^relationship_destination, as: ^initial_ash_bindings.current, on: field(row, ^relationship.source_attribute) == field( destination, ^relationship.destination_attribute ) ) end AshPostgres.Aggregate.add_aggregates( query, used_aggregates, relationship.destination, false, initial_ash_bindings.current, {query.__ash_bindings__.resource, full_path} ) end end @doc false def maybe_apply_filter(query, _root_query, _bindings, nil, acc), do: {query, acc} def maybe_apply_filter(query, root_query, bindings, filter, acc) do {dynamic, acc} = AshPostgres.Expr.dynamic_expr(root_query, filter, bindings, true, acc) {from(row in query, where: ^dynamic), acc} end end