Handle controller error with GraphQL

[Cyrille_Brun]

System Information

• Strapi Version: 3.6.5
• Operating System:
• Database:
• Node Version:
• NPM Version:
• Yarn Version:

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Hi everyone

I am currently working on a side project in order to try the great cms Strapi.

I have a question concerning error handling in Strapi with graphql. I was playing with the graphql playground and tried some queries/mutations. There is one thing I can’t figure out.

Let’s say I want to register a new user. I use the “register” mutation

It works perfectly.

Now if I omit the password I got this response

which is nice, because I can handle this message on my front-end app. I checked on the strapi’s github to see how it is managed strapi/Auth.js at master · strapi/strapi · GitHub. We can see in the controller the action “register” which returns a BadRequest if the password is empty :

That’s perfect.

Next, I tried the “updateUser” mutation which works pretty well

However, if I let the username empty, I got this error

I checked the “update” action strapi/api.js at master · strapi/strapi · GitHub and we can see a badrequest is returned if the username is empty

I was wondering why I don’t get this error message in the graphql response whereas for the register action I can handle it ? Instead I got “Cannot return null for non-nullable field UsersPermissionsUser.id.” (which I understand, if no user is returned, I can’t access user ID)

If someone can help me
Thanks !