README.md

Legacy Estimator

WARNING: The legacy estimator is only part of the library to provide the functionality of previous versions. You should use the fieldConfig estimator for new projects and migrate old implementations.

Usage

import queryComplexity, {legacyEstimator} from 'graphql-query-complexity';

const rule = queryComplexity({
  estimators: [
    legacyEstimator()
  ]
  // ... other config
});

You can set a custom complexity in the field config:

const Post = new GraphQLObjectType({
  name: 'Post',
  fields: () => ({
    title: { type: GraphQLString },
    text: { type: GraphQLString, complexity: 5 },
  }),
});

The same query would now result in a complexity of 7. 5 for the text field and 1 for each of the other fields.

You can also pass a calculation function in the field config to determine a custom complexity. This function will provide the complexity of the child nodes as well as the field input arguments.

That way you can make a more realistic estimation of individual field complexity values:

const Query = new GraphQLObjectType({
  name: 'Query',
  fields: () => ({
    posts: {
      type: new GraphQLList(Post),
      complexity: (args, childComplexity) => childComplexity * args.count,
      args: {
        count: {
          type: GraphQLInt,
          defaultValue: 10
        }
      }
    },
  }),
});

This would result in a complexity of 60 since the childComplexity of posts (text 5, title 1) is multiplied by the number of posts (args.count).