Can't solve Playground error: Variable \"$input\" of required type \"MemberInput!\" was not provided

Question

I've beat on this issue for what seems like a week and nothing online solves it. No data object is returned, not even "null". I'm converting from a working REST CRUD app to GraphQL. Not as easy as I expected.

My mutation in Playground:

mutation createMember($input: MemberInput!) {
    createMember (input: $input) {
          first_name
          last_name
          user_name
    }
}

Playground Query Variables below: (Not in the headers section.)

{
  "input": {
    "first_name": "John",
    "last_name": "Creston",
    "user_name": "jc"
    }
}

The schema: (The queries work fine and the Member type, an entity in TypeORM, works with them and full REST CRUD.)

input MemberInput {
    first_name: String!
    last_name: String!
    user_name: String!
}

type Mutation {
    createMember(input: MemberInput!): Member!
}

type Query {
    getMembers: [Member]
    getMember(member_id: Int!): Member!
    checkUserName(user_name: String): Member
    checkEmail(email: String): Member
}

I don't see how the resolver could be the problem for this error message but I'll add the Nestjs resolver:

@Mutation('createMember')
  async createMember(@Args('input') input: MemberInput): Promise<Members> {
    console.log('input in resolver: ', input);
    return await this.membersService.addItem(input);
  }

The service works with REST and the queries so that should be a problem. The console.log in the resolver never appears in terminal.

From the Copy CURL button:

curl 'http://localhost:3000/graphql' -H 'Accept-Encoding: gzip,    
deflate, br' -H 'Content-Type: application/json' -H 'Accept: 
application/json' -H 'Connection: keep-alive' -H 'DNT: 1' -H 'Origin: 
http://localhost:3000' --data-binary '{"query":"mutation 
createMember($input: MemberInput!) {\n  createMember (input: $input) 
{\n      first_name\n      middle_initial\n      last_name\n     
user_name\n      pitch\n      main_skill_title\n    \tskill_id_array\n      
skills_comments\n      other_skills\n      links\n      country\n      
email\n      member_status\n  }\n}"}' --compressed

Answer 1

I had same problem, in variables i had comma at the end of last parameter. gql gave me same error.

change this:

{
    "input": {
        "param1": "val1",
        "param2": "val2",
    }
}

to this:

{
    "input": {
        "param1": "val1",
        "param2": "val2" // no comma here
    }
}

Answer 2

A bit complicated to explain but we've probably all be there. I was trying different "solutions" and the remains of one was accidentally left in my JSON data object. The full object has more properties than my brief one above. An array shouldn't be "[]" in JSON. I was getting tired and desperate last night. I changed the resolver to what I posted above but it didn't fix the problem because of the experiment in JSON caused the same error as before. So I was looking in the wrong places. Once I noticed and removed the quotes my full object's data was posted to the Postgres db.

The code above works.

It would be nice if there were more specific GraphQL errors. I suspected that this one is very general but that didn't help. It didn't indicate that the original problem was in the resolver and later that I had a data input error.