Question
Answer and Explanation
In the context of Swagger (now known as the OpenAPI Specification), a "primary key related field" doesn't have a direct, built-in definition within the specification itself. Instead, it refers to a common practice when designing APIs that involve relationships between entities, specifically how you represent foreign key relationships and identify linked resources through primary keys. This concept is implemented through common patterns rather than as a specific field type.
When describing an API using Swagger, relationships between entities are often represented via fields that contain the primary key of the related entity. For example, in a REST API, a ‘book’ resource might include an 'authorId' field, where authorId is the primary key of an ‘author’ resource. This field acts as a foreign key, linking to the related author record. In your Swagger specification, you’d describe this field using standard data types like 'integer' or 'string', depending on your primary key representation.
Key characteristics of what is commonly understood as a "primary key related field" in a Swagger document:
1. Data Type: It's typically represented using scalar types like integer, string, UUID, or other simple types that are used to define primary keys in database systems. The specific data type will match the data type used for the primary key of the related entity.
2. Foreign Key Role: This field acts as a foreign key, referencing a different object. Instead of embedding the full related object (which could lead to huge responses and redundancy), only the primary key is included to identify the relationship.
3. Descriptive Schema: In Swagger, this field is usually defined as part of an object's schema. The schema defines the data type of the field and can also include a description to clarify its relationship (e.g., 'The ID of the Author').
4. No Special Swagger Keyword: The OpenAPI Specification itself does not have a dedicated keyword or type specifically for a 'primary key related field'. Instead, the relationship is understood from the context, specifically the naming conventions and schema descriptions you provide.
Example in Swagger (OpenAPI) definition:
"Book": {
"type": "object",
"properties": {
"id": {
"type": "integer",
"description": "The primary key of the book."
},
"title": {
"type": "string"
},
"authorId": {
"type": "integer",
"description": "The ID of the author of this book."
}
}
}
In this example, authorId is a "primary key related field" representing a foreign key. It links to the id field in the "Author" resource, which is not defined here but would have its own schema.
In summary, there's no explicit "primary key related field" in Swagger. It's a concept represented by fields that contain the primary key of related objects. It is important to maintain clear descriptions for API documentation and implementation.