How to dynamically set variables in mutation with

问题:

In my component, I am using react-adopt, to compose graphql queries and mutations, so that my render props don't get too messy. I have the following code:

This is my mutation, it takes one argument - planID.

const CREATE_ORDER_MUTATION = gql`
  mutation CREATE_ORDER_MUTATION($planID: String!) {
    createOrder(planID: $planID) {
      planID
      name
      description
      subscriptionType
      images
      subscriptionType
      pricePerMonth
}
}

This is the adopt function, it takes a couple of mutations, one of which is createOrder. The way Apollo works is that I need to pass variables prop to createOrder component here. The problem is, I don't have the planID at this point. planID is available only inside of the actual component.

const Composed = adopt({
  toggleCart: <Mutation mutation={TOGGLE_CART_MUTATION} />,
  createOrder: <Mutation mutation={CREATE_ORDER_MUTATION} />,
});

My component looks like this. I have the planID available here, but how can I pass it as an argument to mutation?!

render() {
const { plan } = this.props;
return (
  <Composed>
    {({ toggleCart, createOrder }) => {
      const handleAdd = () => {
        toggleCart();
        Router.push('/waschingmachine');
        createOrder();
      };
      return (
        <StyledPlan>
          <h1>{plan.name}</h1>
          <p>{plan.description}</p>
          <img src={`static${plan.images[0]}`} alt="blue1" />
          <h2>{plan.pricePerMonth / 100} EUR</h2>
          <div className="buttons">
            <Link
              href={{
                pathname: '/plan',
                query: { id: plan.id },
              }}
            >
              <button type="button">info</button>
            </Link>
            <button onClick={handleAdd} type="button">
              Select Plan
            </button>
          </div>
        </StyledPlan>
      );
    }}
  </Composed>
);
}

If there is no way to solve it this way, how would you approach it differently?

回答1:

The mutate function passed in the rendered children can be called with options. Options can include variables used in the GraphQL mutation string. ^[1].

This means that you can call the createOrder mutation function like so.

createOrder({ variables: { planID: 'some plan id' } });

Given the dynamic nature of planID, there are a number of ways to implement this. One of which is to use data attributes as below:

A data attribute can be set on for the plan id on the button .

<button onClick={handleAdd} data-planid={plan.id} type="button">
      Select Plan
</button>

handleAdd can be refactored to get the planid from the target dataset attribute and invoke createOrder with planID variable.

const handleAdd = event => {
    const planID = event.target.dataset.planid;
    toggleCart();
    Router.push('/waschingmachine');
    createOrder({ variables: { planID } });
};

Another is to directly pass planID to handleAdd when calling it in the onClick prop for the button.

<button onClick={() => handleAdd(plan.id)} type="button">
      Select Plan
</button>

Then update the handler

const handleAdd = planID => {
    toggleCart();
    Router.push('/waschingmachine');
    createOrder({ variables: { planID } });
};

There are tradeoffs to both approaches. For the earlier approach, the planid are set in the DOM as attributes and can be read later. While for the later one, N handlers are created for N plans and are kept in memory.

回答2:

Here is how you can pass arguments through react-adopt way into your inner mutations mapper:

// In a nutshell, `react-adopt` allows you to pass props to your `Composed`
// component, so your inner `mapper` can access those props to pass them to 
// your <Query> or <Mutation>

// Here's your initial `Composed` component from above
const Composed = adopt({
  // `planId` is passed from below via props (see `<ContainerComponent />) 
  toggleCart: ({ planId, render }) => (
    <Mutation mutation={TOGGLE_CART_MUTATION} variables={{ planId }}>{render}</Mutation>,
    ),
  // `planId` is passed from below via props (see `<ContainerComponent />)
  createOrder: ({ planId, render })=> (
    <Mutation mutation={CREATE_ORDER_MUTATION} variables={{ planId }}>{render}</Mutation>                 
  )
});

// `<ContainerComponent />` will take a plan as its props and passed `planId` to 
// the `<Composed />` component
const ContainerComponent = ({ plan }) => (
  <Composed planId={plan.id}>
    {({ toggleCart, createOrder }) => {      
      const handleAdd = e => {
        e.preventDefault();
        toggleCart();
        // ...
        createOrder();
        // ...
      };

      // Whatever your UI needs you can pass them here via here
      return <YourPresentationComponent onClick={handleAdd} />;
    }}
  </Composed>
)

// Now all you need to do is to pass `plan` from your render() to the 
// <ContainerComponent /> (This is the render() where you return your 
render() {
  const { plan } = this.props;
  return <ContainerComponent plan={plan} />
}

Hopefully this can be helpful to solve your issue! Just a side note, you can also get the previous mapper value and pass them onto the next mapper fn as part of the argument, see below:

const Composed = adopt({ 
  // Here you can retrieve the actual `plan` by using `userId` and pass the result 
  // into your next children mapper fn to consume
  plan: ({ userId, render }) => (
   <Query query={GET_PLAN_GRQPHQL} variables={{ userId }}>{render}</Query>
  ),
  // `plan` is actually coming from above <Query /> component 
  toggleCart: ({ plan, render }) => { //... },
  createOrder: ({ plan, render }) => { //...}
});