API Validation

In the Data API Schema, we talked about how to define the API Schema, and also mentioned the validators field feature could assist each request parameter to check the format. In the chapter we will talk more about the validator's usage and currently how many validators VulcanSQL supports.

Parameter Validators

The validators field in the API Schema is an array type, also you could use the multiple validators to check the format like below example:

urlPath: /orders/order_id
request:
  - fieldName: orders_id
    fieldIn: path
    validators:
      - required
      - uuid

In the above example, because our request path parameter order_id is UUID format, and we require users to provide the path parameter when sending a request, so we could combine uuid validator and required validators ( but if you don’t set required, the VulcanSQL will make it be required default.

Set the args in the validator

Some validators could set the args field to give some extra restrict, e.g: number and date validators:

urlPath: /orders
request:
  - fieldName: create_date
    fieldIn: query
    validators:
      - name: date
        args:
          format: 'YYYY-MM-DD'
  - fieldName: price
    fieldIn: query
    validators:
      - name: number
        args:
          min: 0
          max: 1000000

As you see, the args will have different fields by each validator, and when setting the args, we should use the name field to set the validator name to make the YAML format correct.

Error Response when sending request

When the validator check the format and it's failed, it will return the error response, below is the example:

# order.yaml
urlPath: /orders
request:
  - fieldName: price
    fieldIn: query
    validators:
      - name: number
        args:
          min: 0
          max: 1000000

Then when you sent the request with GET<endpoint>/api/orders?price=1000001, it will return an HTTP status code with 400 and the below message:

{
  code: 'vulcan.userError',
  message: 'The input parameter is invalid, it should be integer type',
}

Current support validators

required validator

Make the request parameter field the required parameter, use the Joi to check required. The args field:

• disallow - Array type. Specifies what input values are also not as required and if the parameter value appeared in the disallow value, send the response with the error message.

# dep_users.yaml
urlPath: /dep_users
request:
  - fieldName: department
    fieldIn: query
    validators:
      - name: required
        args:
          disallow:
            - ''
            - ' '
            - 'null'

Then when you sent the request with GET<endpoint>/api/dep_users?department=null, it will return an HTTP status code with 400 and the below message:

{
  code: 'vulcan.userError',
  message: 'The input parameter is invalid, it should be required',
}

uuid validator

Validate the UUID format for the request parameter, use the **Joi to check UUID.** The args field:

• version - String type. Specifies the UUID version. the option could be uuidv1, uuidv4 or uuidv5

# order.yaml
urlPath: /orders/:id
request:
  - fieldName: id
    fieldIn: path
    validators:
      - name: uuid
        args:
          version: uuidv5

date validator

Validate whether the request parameter is Date Format type or not, use the dayjs package to be the format source. The args field:

• format - String type. Specifies the date needed format, supported ISO_8601 token, e.g: 'YYYYMMDD', 'YYYY-MM-DD', 'YYYY-MM-DD HH:mm'.

# order.yaml
urlPath: /orders
request:
  - fieldName: create_date
    fieldIn: query
    validators:
      - name: date
        args:
          format: 'YYYY-MM-DD' # make the date only support 'YYYY-MM-DD' format

string validator

Validate whether the request parameter is a String type, use the Joi to check String ( including the args field ). The args field:

• format - String type. Specifies the string format, and supports regular expression. Use the Joi pattern to check.
• length - Number type. Specifies the String's exact length.
• max - Number type. Specifies the minimum number of string characters.
• min - Number type. Specifies the maximum number of string characters.

# bank_account.yaml
urlPath: /bank_account/id
request:
  - fieldName: id
    fieldIn: path
    validators:
      - name: string
        args:
          format: '^09[0-9]{8}$'
          length: 10

integer validator

Validate whether the request parameter is an Integer type, use the Joi to check Integer. ( including the args field ). The args field:

• max - Number type. Specifies the maximum integer value.
• min - Number type. Specifies the minimum integer value.
• greater - Number type. Specifies that the integer value must be greater than the limit.
• less - Number type. Specifies that the value must be less than the limit.

# bank_account.yaml
urlPath: /youth_users
request:
  - fieldName: age
    fieldIn: query
    validators:
      - name: integer
        args:
          - greater: 10
          - less: 19