View Source Loupe.Ecto.Context (Loupe v0.7.0)
The context is the structure that goes through the query building process. It includes the user assigns which are passed down below in the ecto definition, but also includes a couple fields to make sure that query info are validated beforehand.
ecto-schema-validations
Ecto schema validations
Some things are validated before executing the query to avoid crashes during the query execution. These validations includs:
- Validate that the fetched schema exists and a valid schema.
- Validate that the queried field are valid on the attached schema and allowed.
It also extract the query bindings which are the queries associations and
validates them. This is meant to allow someone to use posts.comments.user.name
in a query and directly join the posts's comments and comments's user to filter
its name.
binding-naming
Binding naming
Ecto requires named bindings to be atom (which makes total sense). To avoid generating atoms at runtimes in the system, any non-reserverd keyword is cast as string when generating the AST.
When building the Ecto query, the join statements uses bindings from a predefined
set that you can find a the bottom of this file under the @binding_keys module
attribute.
Link to this section Summary
Functions
Casts a sigil expression using the context's implementation
Initializes a query by scoping from the implementation
Instanciates a context with an implementation and some assigns. The assigns will be passed down to the implementation during to query building process to alter the definition dynamically.
Puts bindings in the context validation that bindings are either valid fields or associations.
Puts root schema in the context validating it's a valid Ecto schema
Checks if a given schema field is allowed
Gets implementation schema fields
Gets implementation schemas
Same as selectable_fields/1 but for the root schema
Gets fields that can be selected infering the foreign keys. For instance,
if someone allows user belong_to relationship on Post̀, the user_id
is automatically returned and there is no need for it to be allowed.
Sorts binding in order to be join in order
Link to this section Types
@type assigns() :: assigns()
@type binding_path() :: [atom()]
@type bindings() :: %{required(binding_path()) => atom()}
@type implementation() :: module()
@type schema() :: Ecto.Queryable.t()
@type t() :: %Loupe.Ecto.Context{ assigns: assigns(), bindings: bindings(), implementation: implementation(), root_schema: schema() }
Link to this section Functions
@spec cast_sigil(t(), Loupe.Language.sigil_definition()) :: any()
Casts a sigil expression using the context's implementation
@spec initialize_query(t()) :: Ecto.Query.t()
Initializes a query by scoping from the implementation
@spec new(implementation(), assigns()) :: t()
Instanciates a context with an implementation and some assigns. The assigns will be passed down to the implementation during to query building process to alter the definition dynamically.
Puts bindings in the context validation that bindings are either valid fields or associations.
Puts root schema in the context validating it's a valid Ecto schema
Checks if a given schema field is allowed
Gets implementation schema fields
Gets implementation schemas
Same as selectable_fields/1 but for the root schema
Gets fields that can be selected infering the foreign keys. For instance,
if someone allows user belong_to relationship on Post̀, the user_id
is automatically returned and there is no need for it to be allowed.
@spec sorted_bindings(t()) :: [{binding_path(), atom()}]
Sorts binding in order to be join in order