title: graphql mutation gives syntax error: Expected Name
body: <p>I am trying to implement mutations with a variable. But I get the following error:</p>
  
  <pre><code>"Syntax Error GraphQL request (3:22) Expected Name, found $
  
  2:     mutation {
  3:       createProperty($property) {
                          ^
  4:         id
  "
  </code></pre>
  
  <p>My schema definitely doesn't say anything about a name, that's why I think this error is so strange.. I also don't think the documentations about graphql / apollo are very good.</p>
  
  <p><strong>Calling the mutation from client:</strong></p>
  
  <pre><code>const property = {
      title: 'First house',
      cost: 849,
      bedrooms: 3,
      bathrooms: 2,
      car_spaces: 1,
      house_size: 60,
    };
  
    const createPropertyQuery =
    graphql(gql`
      mutation {
        createProperty($property) {
          id
        }
      }
    `, {
        options: {
          variables: {
            property,
          },
        },
      });
  
  
    const { data } = await apolloClient.query({
      query: createPropertyQuery,
    });
  </code></pre>
  
  <p><strong>Schema:</strong></p>
  
  <pre><code>type Property {
      title: String!
      cost: Float
      user: User
      bedrooms: Int!
      bathrooms: Int!
      car_spaces: Int!
      house_size: Int!
  }
  input propertyInput {
      title: String!
      cost: Float
      bedrooms: Int!
      bathrooms: Int!
      car_spaces: Int!
      house_size: Int!
  }
  
  type RootMutation {
      createProperty (
          property: propertyInput
      ): Property
  }
  </code></pre>