Confusion with ArrayOptions.contains

[cheersmas]

I've two use cases here:

• Only one option object must have isCorrect: true for Multiple Choice Question for single answers
• More than one option objects must have isCorrect: true for Multiple Choice Question for multiple answers
  the flag isCorrect for at least one option object in an array has to be true.
• For each question there must be at least one correct option.

I've two Schemas one for a Question and one for Option.
The OptionsDTO defines the option's schema and the QuestionsDTO has an array of options inside them.
I'm trying to create such schema using the contains option in the ArrayOptions.
It throws a status code 500 with undefined is not an object (evaluating 'value.options.reduce') message.

What would be the correct way to achieve this?

const OptionsDTO = t.Object({
  text: t.String(),
  isCorrect: t.Boolean()
})

const QuestionDTO = t.Object({
  text: t.String(),
  options: t.Array(OptionsDTO, {
    minItems: 2,
    maxItems: 5,
    contains: t.Object({
      text: t.String(),
      isCorrect: t.Literal(true)
    })
  })
})

[sinclairzx81]

@cheersmas Heya, have you tried minContains and maxContains ?

import { Type } from '@sinclair/typebox'
import { Value } from '@sinclair/typebox/value'

const Answer = Type.Object({
  text: Type.String(),
  isCorrect: Type.Boolean()
})
const SingleChoice = Type.Object({
  text: Type.String(),
  options: Type.Array(Answer, {
    minContains: 1, // expect ONLY 1 element to contain schematic
    maxContains: 1,
    contains: Type.Object({
      text: Type.String(),
      isCorrect: Type.Literal(true)
    })
  })
})
const MultiChoice = Type.Object({
  text: Type.String(),
  options: Type.Array(Answer, {
    minContains: 1, // expect at least 1 element to contain schematic
    contains: Type.Object({
      text: Type.String(),
      isCorrect: Type.Literal(true)
    })
  })
})
// ------------------------------------------------------------------
// SingleChoice
// ------------------------------------------------------------------
const A = Value.Check(SingleChoice, { // true
  text: 'SingleChoice',
  options: [
    { text: 'A', isCorrect: true },
    { text: 'B', isCorrect: false }
  ]
})
const B = Value.Check(SingleChoice, { // false
  text: 'SingleChoice',
  options: [
    { text: 'A', isCorrect: true },
    { text: 'B', isCorrect: true }
  ]
})
// ------------------------------------------------------------------
// MultiChoice
// ------------------------------------------------------------------
const C = Value.Check(MultiChoice, { // true
  text: 'MultiChoice',
  options: [
    { text: 'A', isCorrect: true },
    { text: 'B', isCorrect: true }
  ]
})
const D = Value.Check(MultiChoice, { // false
  text: 'MultiChoice',
  options: [
    { text: 'A', isCorrect: false },
    { text: 'B', isCorrect: false }
  ]
})

[cheersmas]

I tried this, although your answer validates correctly. It isn't working for me when I use it to validate my body in a POST request in Elysia. I'm using bun.
It throws the same error. If I try to debug this, on turning on caught exceptions it lands me here. The value here is:

You see the value is an array and it tries to get the options key from it which is undefined:

Here is my complete server code.

import { Elysia, t } from 'elysia'
import mongoose from 'mongoose'
import { Quiz } from './models/Quiz'

const PORT = 8000
const MONGODB_PATH = 'mongodb://localhost:27017/quiz_db'

const OptionDTO = t.Object({
  text: t.String(),
  isCorrect: t.Boolean()
})

const QuestionDTO = t.Object({
  text: t.String(),
  options: t.Array(OptionDTO, {
    minContains: 1,
    maxContains: 1,
    // minItems: 2,
    // maxItems: 5,
    contains: t.Object({
      text: t.String(),
      isCorrect: t.Literal(true)
    })
  })
})

const QuizDTO = t.Object({
  text: t.String(),
  questions: t.Array(QuestionDTO, { minItems: 1, maxItems: 10 })
})

async function main() {
  const app = new Elysia()

  try {
    await mongoose.connect(MONGODB_PATH)
  } catch (err) {
    console.error(err);
  }

  app.get('/', () => 'hello elysia')
  app.post('/api/quiz', async ({ body, ...rest }) => {
    console.log('something')
  }, {
    body: QuizDTO,
  })
  app.get('/api/quiz', async (context) => {
    try {
      const quizzes = await Quiz.find({});
      return quizzes
    } catch (err) {
      return
    }
  })
  app.listen(PORT)

  console.log(`running at: ${app.server?.hostname}:${app.server?.port}`)
}

main().catch(console.error)

[sinclairzx81]

@cheersmas This looks like a compiler bug as the check function should never throw. The issue appears to be the incorrect value.options.reduce (which should just be value.reduce), I can publish a patch for this within the next hour.

How easy is it for you to update TypeBox in Elysia?

[sinclairzx81]

@cheersmas Hi. I have just published a fix for this which should prevent errors being thrown (this was a good catch)

The update is on @sinclair/typebox@0.31.17 so you will need to ensure Elysia is on this version. Associated PR can be found #608.

[cheersmas]

Since, it is a minor version. I think a reinstall of ElysiaJS should fix this. I've raised a PR here
elysiajs/elysia#228