withMutation.js

// wrapper

import { graphql } from 'react-apollo';
import gql from 'graphql-tag';

export default function withMutation({name, args}) {

  let mutation;

  if (args) {
    const args1 = _.map(args, (type, name) => `$${name}: ${type}`); // e.g. $url: String
    const args2 = _.map(args, (type, name) => `${name}: $${name}`); // e.g. $url: url
    mutation = `
      mutation ${name}(${args1}) {
        ${name}(${args2})
      }
    `
  } else {
    mutation = `
      mutation ${name} {
        ${name}
      }
    `
  }

  return graphql(gql`${mutation}`, {
    props: ({ownProps, mutate}) => ({
      [name]: (vars) => {
        return mutate({ 
          variables: vars,
        });
      }
    }),
  });
}

// component

import { withMutation } from 'withMutation.js';

const MyComponent extends Component {
  fetchMetaData() {
    this.props.getMetaData({url: this.props.url}) /* get url from somewhere */
      .then(result => {/* do something with the result */})
      .catch(error => {/* do something with the error */})
  },
  render() {
    return (/* render component here */)
  }
}

const mutationOptions = {
  name: 'getMetaData',
  args: {url: 'String'},
}

export default withMutation(options)(MyComponent);

// schema

const schema = [`
type JSON

type Mutation {
  getMetaData(url: String) : JSON
}
`];

// resolvers

import GraphQLJSON from 'graphql-type-json';

const rootResolvers = {
  JSON: GraphQLJSON, 
  Mutation: {
    getMetaData(root, { url }, context) {
      const data = ... // make some kind of API call
      return data;
    },
  },
};