Sequelize-typescript: Validate not working properly

[bschveitzer]

When calling instance .validate() it returns me a sequelize object instead of ValidationError object.

Is that supposed to happen ?

[RobinBuschmann]

Hey @bschveitzer. Can you post a code example and your sequelize version please? Thank you :)

[Cyberuben]

Hi @RobinBuschmann,

as I see this issue has gone silent, and I'm experiencing the same issue, I'll post the code here:

let user = new User(data);
let errors = await user.validate();
console.log(errors);

this will output an instance of the user that I just created, no validation errors.

I'm using VSCode and the intellisense shows the following:

There is in fact an error in the data I'm supplying, as it is thrown when I'm trying to save the model, but something here seems to go wrong.

[Cyberuben]

To elaborate on the issue: I found that this problem occurs whenever you supply a validator function that returns either true or false

With the following code:

    // within my model definition
    @Unique
    @IsEmail
    @Is("emailAvailable", emailAvailable)
    @Column
    email: string;

works with the following validator:

const emailAvailable = async function (email: string): Promise<void> {
    const user = await User.findOne({ where: { email } });

    if (user != null && user.id !== this.id) {
        throw new Error("Email already in use");
    }
};

fails with the following validator:

const emailAvailable = async function (email: string): Promise<boolean> {
    const user = await User.findOne({ where: { email } });

    return user == null || user.id === this.id;
};

I'm not sure if this is intended behavior, as custom validators for Sequelize seem to be badly documented, but at least I found the source for my issues.

[RobinBuschmann]

Ah ok, I got it. Validation works differently for the two latest sequelize major versions. While validate() in version 3 resolves with an error if one exists, it rejects the promise in version 4:

user.validate().then(err => ...) // 3.X
user.validate().catch(err => ...) // 4.X

sequelize-typescript currently supports both major versions. So the actual issue is in the sequelize-typescript typings. It should be something like
validate(...): Promise<ValidationError /*v3*/ | Model> than the current type definition.

[RobinBuschmann]

Is fixed with [email protected]