Contracts

Contracts are objects that define input and output validation rules for endpoints and restrict the access to the endpoint given an access condition.

Attributes

Contracts can have the following attributes:

• roles
• payload
• query
• response

Example contract:

contract AddFriend {
  roles {
    member
  }
  payload {
    properties {
      user_id User
    }
  }
  response {
    properties {
      success const @value(true)
    }
  }
}

The payload, query and response attributes can take multiple options separated by a pipe (|). They can also take a modifier.

contract MyContract {
  response
    | Result const @value("success")
    | Error {
      properties {
        message str
        code int
      }
    }
}

Accepted modifiers:

• Error: wraps the property in a Result.Error object
• Result: wraps the property in a Result.Result object

Using contracts

Contracts can be used by routes and collection functions.

Route usage:

import { contracts } from '../../.aeria/out/index.js'

router.POST('/addFriend', addFriend, contracts.AddFriend)
router.POST('/removeFriend', removeFriend, contracts.RemoveFriend)