# Abstract services to serialize Nit objects to different formats
#
-# This module declares the `auto_serializable` annotation to mark Nit classes as serializable.
+# This module declares the `serialize` annotation to mark Nit classes as serializable.
# For an introduction to this service, refer to the documentation of the `serialization` group.
# This documentation provides more technical information on interesting entitie of this module.
#
# `notify_of_creation` must be redefined.
module serialization is
new_annotation auto_serializable
+ new_annotation serialize
+ new_annotation noserialize
end
# Abstract serialization service to be sub-classed by specialized services.
# Abstract deserialization service
#
# After initialization of one of its sub-classes, call `deserialize`
-interface Deserializer
+abstract class Deserializer
# Main method of this class, returns a Nit object
fun deserialize: nullable Object is abstract
# This method should be redefined for each custom subclass of `Serializable`.
# All refinement should look for a precise `class_name` and call super
# on unsupported classes.
- fun deserialize_class(class_name: String): Object do
- print "Error: doesn't know how to deserialize class \"{class_name}\""
- abort
+ protected fun deserialize_class(class_name: String): nullable Object do
+ if class_name == "Error" then return new Error.from_deserializer(self)
+ return deserialize_class_intern(class_name)
+ end
+
+ # Generated service to deserialize the next available object as an instance of `class_name`
+ #
+ # Refinements to this method will be generated by the serialization phase.
+ # To avoid conflicts, there should not be any other refinements to this method.
+ # You can instead use `deserialize_class`.
+ protected fun deserialize_class_intern(class_name: String): nullable Object do
+ errors.add new Error("Deserialization Error: Doesn't know how to deserialize class \"{class_name}\"")
+ return null
+ end
+
+ # Should `self` keep trying to deserialize an object after an error?
+ #
+ # This behavior takes effect after each attribute deserialization with
+ # errors such as a missing attribute or the value is of the wrong type.
+ # If `keep_going`, the attribute will be skipped but the engine will
+ # deserialize the next attribute.
+ # If `not keep_going`, the engine stops deserializing right away.
+ #
+ # When at `true`, this may cause the accumulation of a lot of entries in `errors`.
+ #
+ # Default at `true`.
+ var keep_going: nullable Bool = null is writable
+
+ # Errors encountered in the last call to `deserialize`
+ var errors = new Array[Error]
+end
+
+# Deserialization got wrong attribute names
+class AttributeTypeError
+ super Error
+
+ # Parent object of the problematic attribute
+ var receiver: Object
+
+ # Name of the problematic attribute in `receiver`
+ var attribute_name: String
+
+ # Deserialized object that isn't of the `expected_type`
+ var attribute: nullable Object
+
+ # Name of the type expected for `attribute`
+ var expected_type: String
+
+ redef fun to_s
+ do
+ var attribute = attribute
+ var found_type = if attribute != null then attribute.class_name else "null"
+
+ return "Deserialization Error: {
+ }Wrong type on `{receiver.class_name}::{attribute_name}` expected `{expected_type}`, got `{found_type}`"
end
end
# Create an instance of this class from the `deserializer`
#
# This constructor is refined by subclasses to correctly build their instances.
- init from_deserializer(deserializer: Deserializer) do end
+ init from_deserializer(deserializer: Deserializer) is nosuper do end
end
redef interface Object
redef class String super DirectSerializable end
redef class SimpleCollection[E] super Serializable end
redef class Map[K, V] super Serializable end
+
+redef class Couple[F, S]
+ super Serializable
+
+ redef init from_deserializer(v)
+ do
+ v.notify_of_creation self
+ var first = v.deserialize_attribute("first")
+ var second = v.deserialize_attribute("second")
+ init(first, second)
+ end
+
+ redef fun core_serialize_to(v)
+ do
+ v.serialize_attribute("first", first)
+ v.serialize_attribute("second", second)
+ end
+end
+
+redef class Ref[E]
+ super Serializable
+
+ redef init from_deserializer(v)
+ do
+ v.notify_of_creation self
+ var item = v.deserialize_attribute("item")
+ init item
+ end
+
+ redef fun core_serialize_to(v)
+ do
+ v.serialize_attribute("item", first)
+ end
+end
+
+redef class Error
+ super Serializable
+
+ redef init from_deserializer(v)
+ do
+ v.notify_of_creation self
+
+ var message = v.deserialize_attribute("message")
+ if not message isa String then message = ""
+ init message
+
+ var cause = v.deserialize_attribute("cause")
+ if cause isa nullable Error then self.cause = cause
+ end
+
+ redef fun core_serialize_to(v)
+ do
+ v.serialize_attribute("message", message)
+ v.serialize_attribute("cause", cause)
+ end
+end