defprotocol Ecto.Queryable do
@moduledoc """
Converts a data structure into an `Ecto.Query`.
"""
@doc """
Converts the given `data` into an `Ecto.Query`.
"""
def to_query(data)
end
defimpl Ecto.Queryable, for: Ecto.Query do
def to_query(query), do: query
end
defimpl Ecto.Queryable, for: Ecto.SubQuery do
def to_query(subquery) do
%Ecto.Query{from: %Ecto.Query.FromExpr{source: subquery}}
end
end
defimpl Ecto.Queryable, for: BitString do
def to_query(source) when is_binary(source) do
%Ecto.Query{from: %Ecto.Query.FromExpr{source: {source, nil}}}
end
end
defimpl Ecto.Queryable, for: Atom do
def to_query(module) do
try do
module.__schema__(:query)
rescue
UndefinedFunctionError ->
message =
if :code.is_loaded(module) do
"the given module does not provide a schema"
else
"the given module does not exist"
end
raise Protocol.UndefinedError, protocol: @protocol, value: module, description: message
end
end
end
defimpl Ecto.Queryable, for: Tuple do
def to_query({source, schema} = from)
when is_binary(source) and is_atom(schema) and not is_nil(schema) do
%Ecto.Query{from: %Ecto.Query.FromExpr{source: from, prefix: schema.__schema__(:prefix)}}
end
end