JSON Validate

Historia

Lanzamiento	Modificaciones
21 R2	Support of JSON Schema draft 2020-12

JSON Validate ( vJson : Object ; vSchema : Object ) : Object

Parámetros	Tipo		Descripción
vJson	Object	→	Objeto JSON a validar
vSchema	Object	→	JSON schema used to validate JSON objects
Resultado	Object	←	Validation status and errors (if any)

Descripción

The JSON Validate command checks the compliance of the vJson JSON contents with the rules defined in the vSchema JSON schema. If the JSON is invalid, the command returns a detailed description of error(s).

In vJson, pass a JSON object containing the JSON contents to be validated.

Note: Validating a JSON string consists of checking that it follows the rules defined in a JSON schema. Esto es diferente de la comprobación de que el JSON está bien formado, que se realiza mediante el comando JSON Parse.

In vSchema, pass the JSON schema to use for the validation. For more information on how to create a JSON schema, you may consult the json-schema.org web site.

Supported JSON schema validation drafts

To validate a JSON object, 4D uses the norm described in a JSON Schema Validation draft document. Several versions of these documents have been produced over time.

4D supports two versions of the draft:

• versión 2020-12 (recomendado). Se soportan todas las partes de la norma, excepto:
  • vocabulary
  • contentEncoding, contentMediaType, and contentSchema (validation of non-JSON content)
  • for references: $dynamicRef/$dynamicAnchor and references in https:...
• versión 4 (implementación heredada, utilizada por defecto). Note that the support of this norm has more limitations than version 2020-12.

Specifying the version to use

The version to use should be inserted in the schema using the $schema key:

• versión 2020-12:

"$schema": "https://json-schema.org/draft/2020-12/schema",

• version 4:

"$schema": "http://json-schema.org/draft-04/schema#",

For compatibility reasons, the version 4 is used if the $schema key is omitted. However, it is recommended to use the version 2020-12 which provides the most reliable controls.

nota

If you declare another schema version using the $schema key, an error is returned.

Validation result

If the JSON schema is not valid, 4D returns a Null object and throws an error that can be caught by an on error call method.

The JSON Validate returns an object that provides the status of the validation. Este objeto puede contener las siguientes propiedades:

Nombre de propiedad	Tipo	Description
success	Boolean	True si vJson está validado, false en caso contrario. If false, the errors property is also returned
errors	Object collection	List of error objects if the vJson is not validated (see below)

Cada objeto de error de la colección errors contiene las siguientes propiedades:

Nombre de propiedad	Tipo	Description
code	Number	Código de error
jsonPath	Text	JSON path that cannot be validated in vJson
line	Number	Line number of the error in the JSON file. This property is filled if the JSON has been parsed by JSON Parse with the * parameter. Otherwise, the property is omitted.
message	Text	Mensaje de error
offset	Number	Line offset of the error in the JSON file. This property is filled if the JSON has been parsed by JSON Parse with the * parameter. Otherwise, the property is omitted.
schemaPaths	Text	JSON path in the schema that causes the validation error

Error list

Details

Se pueden producir los siguientes errores:

Code	**Palabra clave JSON	Message
2	multipleOf	Error while validating against 'multipleOf' key.
3	maximum	El valor proporcionado no debe ser superior al especificado en el esquema ("{s1}").
4	exclusiveMaximum	The value provided should be less than specified in the schema ("{s1}").
5	mínimo	The value provided should not be less than specified in the schema ("{s1}").
6	exclusiveMinimum	The value provided should be greater than specified in the schema ("{s1}").
7	maxLength	The string is longer than specified in the schema.
8	minLength	The string is shorter than specified in the schema.
9	modelo	The string "{s1}" does not match the pattern in the schema:{s2}.
10	additionalItems	Error while validating an array. JSON contains more elements than specified in the schema.
11	maxItems	The array contains more items than specified in the schema.
12	minItems	The array contains less items than specified in the schema.
13	uniqueItems	Error while validating an array. Los elementos no son únicos. Another instance of "{s1}" is already in the array.
14	maxProperties	The number of properties is greater than specified in the schema.
15	minProperties	The number of properties is less than specified in the schema.
16	requerido	Falta la propiedad requerida "{s1}".
17	additionalProperties	No hay propiedades adicionales permitidas por el esquema. The property(ies) {s1} should be removed.
18	dependencias	The property "{s1}" requires the property "{s2}".
19	enum	Error while validating against 'enum' key. "{s1}" does not match any enum element in the schema.
20	type	Tipo incorrecto. El tipo esperado es: {s1}
21	oneOf	El JSON coincide con más de un valor.
22	oneOf	El JSON no coincide con ningún valor.
23	not	El JSON no es válido para el valor 'not'.
24	format	The string does not match ("{s1}")
25	const	Value "{s1}" does not match the 'const' value in the schema.
26	unevalutedProperties	Unevaluated properties are not allowed by the schema. The property(ies) {s1} should be removed.
27	unevalutedItems	Unevaluated array items are not allowed. Item at index {s1} is not covered by any schema.
28	propertyNames	Property name "{s1}" does not validate against the 'propertyNames' schema.
29	contiene	El array no contiene ningún elemento que coincida con el esquema 'contains'.
30	contiene	Array must contain at least {s1} items matching the 'contains' schema, but only {s2} were found.
31	contiene	El array debe contener como máximo {s1} elementos que coincidan con el esquema 'contains', pero se ha encontrado {s2}.
32	requerido	The property "{s1}" requires the property "{s2}" to be present.
35	prefixItems	Array items at the beginning do not match the 'prefixItems' schemas.
36	dependentSchemas	Validation failed against 'dependentSchemas'.
37	$ref	Reference could not be resolved.
38	$ref	Circular reference detected.

Entrada de blog relacionada

Simplify JSON Validation and Boost Robustness

Ejemplo

You want to validate a JSON object with a schema and get the list of validation errors, if any, and store error lines and messages in a text variable:

 var $oResult : Object
 $oResult:=JSON Validate(JSON Parse(myJson;*);mySchema)
 If($oResult.success) //validation successful
    ...
 Else //validation failed
    var $vLNbErr : Integer
    var $vTerrLine : Text
    $vLNbErr:=$oResult.errors.length ///get the number of error(s)
    ALERT(String($vLNbErr)+" validation error(s) found.")
    For($i;0;$vLNbErr)
       $vTerrLine:=$vTerrLine+$oResult.errors[$i].message+" "+String($oResult.errors[$i].line)+Carriage return
    End for
 End if

Ver también

JSON Parse

Propiedades

Número de comando	1456
Hilo seguro	sí