> For the complete documentation index, see [llms.txt](https://deenz.gitbook.io/bq2/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://deenz.gitbook.io/bq2/guides/test-credential.md).

# TestCredential

The [TestCredential](https://github.com/0xdeenz/bq-core-v2/blob/main/packages/lib/src/testCredential.ts) object abstracts most of the Block Qualified logic away, allowing you to easily interact with the protocol. It incorporates an [OpenZeppelin Autotask](https://docs.openzeppelin.com/defender/autotasks) for a [transaction relayer](https://docs.openzeppelin.com/defender/relay), making it easier to onboard users.

## Defining a TestCredential Object

You can define a new TestCredential object with the following syntax:

```js
const testCredential = await TestCredential.init(
    credentialId,
    {
        provider: "provider",
        apiKey: process.env.PROVIDER_KEY
    },
    "network",
    openAnswersHashes
)
```

{% hint style="warning" %}
The value for `openAnswersHashes` needs to be provided for tests that implement an open answers component, as defined for [Block Qualified tests](/bq2/technical-reference/block-qualified-tests.md)
{% endhint %}

{% hint style="info" %}
To see the officially supported networks, check out the [deployed contracts](/bq2/getting-started/deployed-contracts.md)
{% endhint %}

## Grading a Solution to a Test

Once initialized, you can use the TestCredential object to grade solutions to the test:

```js
const result = testCredential.gradeSolution({ multipleChoiceAnswers, openAnswers })
```

Where `result` will be an object containing the following values:

* `grade`: over 100, grade obtained in the test.
* `minimumGrade`: over 100, minimum grade needed to pass the test.
* `pass`: whether the test was passed or not.
* `nQuestions`: number of open answer questions that make up this test.
* `multipleChoiceGrade`: grade obtained in the multiple choice component of this test.
* `openAnswerGrade`: grade obtained in the open answer component of this test.
* `multipleChoiceWeight`: percentage that the multiple choice component contributes towards the final grade.
* `openAnswerResults` array containing boolean values indicating the result for each open answer question.

## Generating and Verifying a Solution Proof

You can generate a test solution proof as described in [Block Qualified Proofs](/bq2/guides/proofs.md) by calling:

```js
const proof = await testCredential.generateSolutionProof(identity, { multipleChoiceAnswers, openAnswers })
```

Where the value for `identity` is a valid [Semaphore identity](http://semaphore.appliedzkp.org/docs/guides/identities) that is then added to a given group, as described in the [Block Qualified contracts](/bq2/technical-reference/contracts.md#solving-a-test).

{% hint style="info" %}
The TestCredential object takes care of generating additional proofs when the credential being solved is restricted.
{% endhint %}

You can then verify this proof by calling:

```js
const proofIsValid = await testCredential.verifySolutionProof(proof)
```

Which will return `true` or `false`.

## Sending a Solution Transaction

You can use the implemented [OpenZeppelin Relayer](https://docs.openzeppelin.com/defender/relay) to send this transaction free of gas.

```js
await testCredential.sendSolutionTransaction(proof)
```

{% hint style="info" %}
This helps in increasing privacy, since all solving transactions get sent from the same relayer address.
{% endhint %}

## Generating and Verifying a Rating Proof

You can generate a rating proof as described in [Rating the Credential Issuer](/bq2/guides/functionalities/credential-issuer-rating.md) by calling:

```js
const rateProof = await testCredential.generateRateIssuerProof(identity, rating, comment)
```

Where the value for `identity` is a valid [Semaphore identity](http://semaphore.appliedzkp.org/docs/guides/identities) that must have already gained this test credential.

You can then verify this proof by calling:

```js
const proofIsValid = await testCredential.verifyRateIssuerProof(rateProof)
```

Which will return `true` or `false`.

## Sending a Rating Transaction

You can use the implemented [OpenZeppelin Relayer](https://docs.openzeppelin.com/defender/relay) to send this transaction free of gas.

```js
await testCredential.sendRateIssuerTransaction(rateProof)
```

{% hint style="info" %}
This helps in increasing privacy, since all rating transactions get sent from the same relayer address.
{% endhint %}