annotation¶

Annotation allow metadata to be declared and used in data model constructs. These are extremely useful for tooling and applications to

Annotations are named and applicable target constructs (record, entity, enum, trait, service, library, union, key, udt, field, keyfield) are defined as part of the declaration along with attributes.

annotation PII ( record, entity, field ) {
    Sensitivity : SensitivityLevelType
}

enum SensitivityLevelType { Low, Medium, High }

Given the defintion above, it is possible to annotate records, entities or fields with PII. As the field Sensitivity is mandatory it needs to be specified, otherwise an error will be reported.

@PII( SensitivityLevelType.Low )
record Employee {
    Name : string

    @PII(SensitivityLevelType.High)
    Salary : double
}

Built-in Annotations¶

@alfa.lang.Deprecated : Used to denote the target definition has been deprecated and may be removed in future.
@alfa.lang.IgnoreServiceWarnings : To be used against a service to ignore references to unscoped trait types being flagged as an error ( as a transitive closure of a trait cannot be fully determined, which is potential issue between versions )
@alfa.rt.SkipUnknownFields : Ignore unknown fields when reading data for given type. Analogous to JSON Schema permitAdditionalProperties.
@alfa.rt.http.Get : Annotate against a service or library function to indicate when used as REST APIs, the method is considered a HTTP GET.
@alfa.rt.http.Put : HTTP PUT
@alfa.rt.http.Post : HTTP POST
@alfa.rt.http.Delete : HTTP DELETE
@alfa.db.Table : Type considered persistable. Numerous parameters to enable storage on Cloud Stores, Big Data, RDBMS or ObjectStores.