Added basic schema to field-configuration

source/data/field-configuration.mjs

@@ -1,8 +1,8 @@
-import { Data_Validation_Failed, Data_Coercion_Failed } from '@efforting.tech/errors';
+import { Data_Validation_Failed, Data_Coercion_Failed, Superfluous_Data_Field } from '@efforting.tech/errors';
 
 export class Field_Configuration {
-	constructor(name, validation_function=null, coercion_function=null, expected_description=undefined) {
-		Object.assign(this, { name, validation_function, coercion_function, expected_description });
+	constructor(validation_function=null, coercion_function=null, factory_function=null, expected_description=undefined) {
+		Object.assign(this, { validation_function, coercion_function, factory_function, expected_description });
 	}
 
 	check_validation(value) {
@@ -11,29 +11,36 @@ export class Field_Configuration {
 	}
 
 	validate(value, target=undefined) {
-		const { validation_function, name, expected_description } = this;
+		const { validation_function, expected_description } = this;
 		if (!this.check_validation(value)) {
 			throw new Data_Validation_Failed({
-				name, validation_function, value,
+				validation_function, value,
 				target, expected_description,
 			});
 		}
 	}
 
 	coerce(value, target=undefined) {
-		const { coercion_function, name, expected_description } = this;
+		const { coercion_function, expected_description } = this;
 		try {
 			return coercion_function ? coercion_function(value) : value;
 		} catch (e) {
 			throw new Data_Coercion_Failed({
-				name, coercion_function, value,
+				coercion_function, value,
 				target, expected_description,
 				upstream_error: e,
 			})
 		}
 	}
 
-	load(value, target=undefined) {
+	load(value=undefined, target=undefined) {
+
+		const { factory_function } = this;
+
+		if ((value === undefined) && factory_function) {
+			value = factory_function(target);
+		}
+
 		const coerced_value = this.coerce(value, target);
 		this.validate(coerced_value, target);
 		return coerced_value;
@@ -41,3 +48,32 @@ export class Field_Configuration {
 
 
 }
+
+
+export class Schema {
+
+	constructor(field_schema) {
+		Object.assign(this, { field_schema });
+	}
+
+	load(value={}, target=undefined) {
+		const { field_schema } = this;
+
+		for (const [value_name, value_value] of Object.entries(value)) {
+			if (!field_schema[value_name]) {
+				throw new Superfluous_Data_Field({
+					field_value: value_value, field_name: value_name, target,
+				});
+			}
+		}
+
+		const result = {};
+		for (const [field_name, field_config] of Object.entries(field_schema)) {
+			const sub_target = { schema: this, field_name, field_config, parent_target: target };
+			result[field_name] = field_config.load(value[field_name], sub_target);
+		}
+
+		return result;
+	}
+
+}