HOC

Installation

The HOC library is included in the core @apollo/client package:

1
npm install @apollo/client

You then import the library's symbols from @apollo/client/react/hoc.

graphql(query, [config])(component)

1
import { graphql } from '@apollo/client/react/hoc';

The graphql() function is the core of Apollo's HOC API. Use this function to create higher-order components that can execute queries and update reactively based on the data in your Apollo store.

The graphql() function returns a function that "enhances" any component with reactive GraphQL capabilities. This follows the React

The graphql() function can only provide access to your GraphQL data if there is an

The behavior of your component enhanced with the graphql() function will be different depending on if your GraphQL operation is a

Examples

You can use the graphql() function like this:

1
function TodoApp({ data: { todos } }) {
2
  return (
3
    <ul>
4
      {todos.map(({ id, text }) => (
5
        <li key={id}>{text}</li>
6
      ))}
7
    </ul>
8
  );
9
}
10

11
export default graphql(gql`
12
  query TodoAppQuery {
13
    todos {
14
      id
15
      text
16
    }
17
  }
18
`)(TodoApp);

You can also define an intermediate function and hook up your component with the graphql() function like this:

1
// Create our enhancer function.
2
const withTodoAppQuery = graphql(gql`query TodoAppQuery { ... }`);
3

4
// Enhance our component.
5
const TodoAppWithData = withTodoAppQuery(TodoApp);
6

7
// Export the enhanced component.
8
export default TodoAppWithData;

The config object

Before we look into the specific behaviors of each operation, let's look at the config object. The config object is the second argument you pass into the graphql() function, after your GraphQL document. The config is optional and allows you to add some custom behavior to your higher order component.

1
export default graphql(
2
  gql`query MyQuery { ... }`,
3
  config, // <- The `config` object.
4
)(MyComponent);

Lets go through all of the properties that may live on your config object.

config.options

config.options is an object or a function that allows you to define the specific behavior your component should use in handling your GraphQL data.

The specific options available for configuration depend on the operation you pass as the first argument to graphql(). There are options specific to

You can define config.options as a plain object, or you can compute your options from a function that takes the component’s props as an argument.

Example

1
export default graphql(gql`query MyQuery { ... }`, {
2
  options: {
3
    // Options go here.
4
  },
5
})(MyComponent);

1
export default graphql(gql`query MyQuery { ... }`, {
2
  options: props => ({
3
    // Options are computed from `props` here.
4
  }),
5
})(MyComponent);

config.props

The config.props property allows you to define a map function that takes the props (and optionally lastProps) added by the graphql() function (

The function you define behaves almost exactly like

config.props is most useful when you want to abstract away complex function calls into a simple prop that you can pass down to your component.

Another benefit of config.props is that it also allows you to decouple your pure UI components from your GraphQL and Apollo concerns. You can write your pure UI components in one file and then keep the logic required for them to interact with the store in a completely different place in your project. You can accomplish this by your pure UI components only asking for the props needed to render and config.props can contain the logic to provide exactly the props your pure component needs from the data provided by your GraphQL API.

Example

This example uses

1
export default graphql(gql`query MyQuery { ... }`, {
2
  props: ({ data: { fetchMore } }) => ({
3
    onLoadMore: () => {
4
      fetchMore({ ... });
5
    },
6
  }),
7
})(MyComponent);
8

9
function MyComponent({ onLoadMore }) {
10
  return (
11
    <button onClick={onLoadMore}>
12
      Load More!
13
    </button>
14
  );
15
}

To access props that are not added by the graphql() function, use the ownProps keyword. For example:

1
export default graphql(gql`query MyQuery { ... }`, {
2
  props: ({ data: { liveImage }, ownProps: { loadingImage } }) => ({
3
    image: liveImage || loadingImage,
4
  }),
5
})(MyComponent);

To access lastProps, use the second argument of config.props. For example:

1
export default graphql(gql`query MyQuery { ... }`, {
2
  props: ({ data: { liveImage } }, lastProps) => ({
3
    image: liveImage,
4
    lastImage: lastProps.data.liveImage,
5
  }),
6
})(MyComponent);

config.skip

If config.skip is true, then all of the React Apollo code is skipped entirely. Your component behaves as if the graphql() function isn't there at all.

You can also pass a function to config.skip. If you do, the function takes your component's props and should return a boolean. If the function returns true, then the skip behavior goes into effect.

config.skip is especially useful if you want to use a different query based on some prop. You can see this in an example below.

Example

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export default graphql(gql`query MyQuery { ... }`, {
2
  skip: props => !!props.skip,
3
})(MyComponent);

The following example uses the

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export default compose(
2
  graphql(gql`query MyQuery1 { ... }`, { skip: props => !props.useQuery1 }),
3
  graphql(gql`query MyQuery2 { ... }`, { skip: props => props.useQuery1 }),
4
)(MyComponent);
5

6
function MyComponent({ data }) {
7
  // The data may be from `MyQuery1` or `MyQuery2` depending on the value
8
  // of the prop `useQuery1`.
9
  console.log(data);
10
}

config.name

This property allows you to configure the name of the prop that gets passed down to your component. By default, if the GraphQL document you pass into graphql() is a query, then your prop is named

Example

This example uses the

1
export default compose(
2
  graphql(gql`mutation CreateTodoMutation (...) { ... }`, { name: 'createTodo' }),
3
  graphql(gql`mutation UpdateTodoMutation (...) { ... }`, { name: 'updateTodo' }),
4
  graphql(gql`mutation DeleteTodoMutation (...) { ... }`, { name: 'deleteTodo' }),
5
)(MyComponent);
6

7
function MyComponent(props) {
8
  // Instead of the default prop name, `mutate`,
9
  // we have three different prop names.
10
  console.log(props.createTodo);
11
  console.log(props.updateTodo);
12
  console.log(props.deleteTodo);
13

14
  return null;
15
}

config.withRef

By setting config.withRef to true, you can get the instance of your wrapped component from your higher-order GraphQL component using a getWrappedInstance method available on the instance of your higher-order GraphQL component.

You might want to set this to true when you want to call functions or access properties that are defined on your wrapped component’s class instance.

Example

This example uses the

1
class MyComponent extends Component {
2
  saySomething() {
3
    console.log('Hello, world!');
4
  }
5

6
  render() {
7
    // ...
8
  }
9
}
10

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const MyGraphQLComponent = graphql(gql`query MyQuery { ... }`, { withRef: true })(
12
  MyComponent,
13
);
14

15
class MyContainerComponent extends Component {
16
  render() {
17
    return (
18
      <MyGraphQLComponent
19
        ref={component => {
20
          const wrappedInstance = component.getWrappedInstance();
21
          assert(wrappedInstance instanceof MyComponent);
22
          // We can call methods on the component class instance.
23
          wrappedInstance.saySomething();
24
        }}
25
      />
26
    );
27
  }
28
}

config.alias

Use this property to configure the name of your higher order component wrapper. For example, if you set config.alias to 'withCurrentUser', your wrapper component display name becomes withCurrentUser(${WrappedComponent.displayName}) instead of Apollo(${WrappedComponent.displayName}).

The default display name for React Apollo components is Apollo(${WrappedComponent.displayName}). This pattern is used by most React libraries that make use of higher order components. However, this might get confusing when you are using more than one higher order component and you look at the

Example

This example uses the

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export default compose(
2
  graphql(gql`query MyQuery { ... }`, { alias: 'withCurrentUser' }),
3
  graphql(gql`query MyQuery { ... }`, { alias: 'withList' }),
4
)(MyComponent);

graphql() options for queries

props.data

The higher-order component created with graphql() feeds a data prop into your component. Like so:

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render() {
2
  const { data } = this.props; // <- The `data` prop.
3
}

The data prop contains the data fetched from your query in addition to some other useful information and functions to control the lifecycle of your GraphQL-connected component. So for example, if we had a query that looked like:

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query ViewerAndTodos {
2
  viewer {
3
    name
4
  }
5
  todos {
6
    text
7
  }
8
}

Your data prop would contain that data:

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render() {
2
  const { data } = this.props;
3

4
  console.log(data.viewer); // <- The data returned by your query for `viewer`.
5
  console.log(data.todos); // <- The data returned by your query for `todos`.
6
}

The data prop has some other useful properties which can be accessed directly from data. For example, data.loading or data.error. These properties are documented below.

Make sure to always check data.loading and data.error in your components before rendering. Properties like data.todos which contain your app’s data may be undefined while your component is performing its initial fetch. Checking data.loading and data.error helps you avoid any issues with undefined data. Such checks may look like:

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render() {
2
  const { data: { loading, error, todos } } = this.props;
3
  if (loading) {
4
    return <p>Loading...</p>;
5
  }
6
  if (error) {
7
    return <p>Error!</p>;
8
  }
9
  return (
10
    <ul>
11
      {todos.map(({ id, text }) => (
12
        <li key={id}>{text}</li>
13
      ))}
14
    </ul>
15
  );
16
}

data.loading

A boolean representing whether or not a query request is currently in flight for this component. This means that a query request has been sent using your network interface, and we have not yet gotten a response back. Use this property to render a loading component.

However, just because data.loading is true it does not mean that you won’t have data. For instance, if you already have data.todos, but you want to get the latest todos from your API data.loading might be true, but you will still have the todos from your previous request.

There are multiple different network states that your query may be in. If you want to see what the network state of your component is in more detail then refer to

Example:

1
function MyComponent({ data: { loading } }) {
2
  if (loading) {
3
    return <div>Loading...</div>;
4
  } else {
5
    // ...
6
  }
7
}
8

9
export default graphql(gql`query MyQuery { ... }`)(MyComponent);

data.error

If an error occurred then this property will be an instance of ApolloError. If you do not handle this error you will get a warning in your console that says something like: "Unhandled (in react-apollo) Error: ...".

Example:

1
function MyComponent({ data: { error } }) {
2
  if (error) {
3
    return <div>Error!</div>;
4
  } else {
5
    // ...
6
  }
7
}
8

9
export default graphql(gql`query MyComponentQuery  { ... }`)(MyComponent);

data.networkStatus

data.networkStatus is useful if you want to display a different loading indicator (or no indicator at all) depending on your network status as it provides a more detailed view into the state of a network request on your component than

1. loading: The query has never been run before and the request is now pending. A query will still have this network status even if a result was returned from the cache, but a query was dispatched anyway.
2. setVariables: If a query’s variables change and a network request was fired then the network status will be setVariables until the result of that query comes back. React users will see this when
   options.variables
   changes on their queries.
3. fetchMore: Indicates that fetchMore was called on this query and that the network request created is currently in flight.
4. refetch: It means that refetch was called on a query and the refetch request is currently in flight.
5. Unused.
6. poll: Indicates that a polling query is currently in flight. So for example if you are polling a query every 10 seconds then the network status will switch to poll every 10 seconds whenever a poll request has been sent but not resolved.
7. ready: No request is in flight for this query, and no errors happened. Everything is OK.
8. error: No request is in flight for this query, but one or more errors were detected.

If the network status is less then 7 then it is equivalent to

Example:

1
function MyComponent({ data: { networkStatus } }) {
2
  if (networkStatus === 6) {
3
    return <div>Polling!</div>;
4
  } else if (networkStatus < 7) {
5
    return <div>Loading...</div>;
6
  } else {
7
    // ...
8
  }
9
}
10

11
export default graphql(gql`query MyComponentQuery  { ... }`)(MyComponent);

data.variables

The variables that Apollo used to fetch data from your GraphQL endpoint. This property is helpful if you want to render some information based on the variables that were used to make a request against your server.

Example:

1
function MyComponent({ data: { variables } }) {
2
  return (
3
    <div>
4
      Query executed with the following variables:
5
      <code>{JSON.stringify(variables)}</code>
6
    </div>
7
  );
8
}
9

10
export default graphql(gql`query MyComponentQuery  { ... }`)(MyComponent);

data.refetch(variables)

Forces your component to refetch the query you defined in the graphql() function. This method is helpful when you want to reload the data in your component, or retry a fetch after an error.

data.refetch returns a promise that resolves with the new data fetched from your API once the query has finished executing. The promise will reject if the query failed.

The data.refetch function takes a single variables object argument. The variables argument will replace variables used with either the query option or the query from your graphql() HOC (depending on whether or not you specified a query) option to refetch the query you defined in the graphql() function.

Example:

1
function MyComponent({ data: { refetch } }) {
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  return <button onClick={() => refetch()}>Reload</button>;
3
}
4

5
export default graphql(gql`query MyComponentQuery  { ... }`)(MyComponent);

data.fetchMore(options)

The data.fetchMore function allows you to do pagination with your query component. To learn more about pagination with data.fetchMore, be sure to read the

data.fetchMore returns a promise that resolves once the query executed to fetch more data has resolved.

The data.fetchMore function takes a single options object argument. The options argument may take the following properties:

• [query]: This is an optional GraphQL document created with the gql GraphQL tag. If you specify a query then that query will be fetched when you call data.fetchMore. If you do not specify a query, then the query from your graphql() HOC will be used.
• [variables]: The optional variables you may provide that will be used with either the query option or the query from your graphql() HOC (depending on whether or not you specified a query).
• updateQuery(previousResult, { fetchMoreResult, variables }): This is the required function you define that will actually update your paginated list. The first argument, previousResult, will be the previous data returned by the query you defined in your graphql() function. The second argument is an object with two properties, fetchMoreResult and variables. fetchMoreResult is the data returned by the new fetch that used the query and variables options from data.fetchMore. variables are the variables that were used when fetching more data. Using these arguments you should return a new data object with the same shape as the GraphQL query you defined in your graphql() function. See an example of this below, and also make sure to read the
  pagination documentation
  .

Example:

1
data.fetchMore({
2
  updateQuery: (previousResult, { fetchMoreResult, variables }) => {
3
    return {
4
      ...previousResult,
5
      // Add the new feed data to the end of the old feed data.
6
      feed: [...previousResult.feed, ...fetchMoreResult.feed],
7
    };
8
  },
9
});

data.subscribeToMore(options)

This function will set up a subscription, triggering updates whenever the server sends a subscription publication. This requires subscriptions to be set up on the server to properly work. Check out the

This function returns an unsubscribe function handler which can be used to unsubscribe later.

A common practice is to wrap the subscribeToMore call within getDerivedStateFromProps and perform the subscription after the original query has completed. To ensure the subscription isn't created multiple times, you can add it to component state. See the example for more details.

• [document]: Document is a required property that accepts a GraphQL subscription created with the gql template string tag. It should contain a single GraphQL subscription operation with the data that will be returned.
• [variables]: The optional variables you may provide that will be used with the document option.
• [updateQuery]: An optional function that runs every time the server sends an update. This modifies the results of the HOC query. The first argument, previousResult, will be the previous data returned by the query you defined in your graphql() function. The second argument is an object with two properties. subscriptionData is result of the subscription. variables is the variables object used with the subscription query. Using these arguments you should return a new data object with the same shape as the GraphQL query you defined in your graphql() function. This is similar to the
  fetchMore
  callback.
• [onError]: An optional error callback.

In order to update the query's store with the result of the subscription, you must specify either the updateQuery option in subscribeToMore or the reducer option in your graphql() function.

Example:

1
class SubscriptionComponent extends Component {
2
  state = {
3
    subscriptionParam: null,
4
    unsubscribe: null,
5
  };
6

7
  static getDerivedStateFromProps(nextProps, prevState) {
8
    if (!nextProps.data.loading) {
9
      // Check for existing subscription
10
      if (prevState.unsubscribe) {
11
        // Only unsubscribe/update state if subscription variable has changed
12
        if (prevState.subscriptionParam === nextProps.subscriptionParam) {
13
          return null;
14
        }
15
        prevState.unsubscribe();
16
      }
17

18
      return {
19
        // Subscribe
20
        unsubscribe: nextProps.data.subscribeToMore({
21
          document: gql`subscription MySubscription {...}`,
22
          variables: {
23
            param: nextProps.subscriptionParam,
24
          },
25
          updateQuery: (previousResult, { subscriptionData, variables }) => {
26
            // Perform updates on previousResult with subscriptionData
27
            return updatedResult;
28
          },
29
        }),
30
        // Store subscriptionParam in state for next update
31
        subscriptionParam: nextProps.subscriptionParam,
32
      };
33
    }
34

35
    return null;
36
  }
37

38
  render() {
39
    ...
40
  }
41
}

data.startPolling(interval)

This function will set up an interval and send a fetch request every time that interval ellapses. The function takes only one integer argument which allows you to configure how often you want your query to be executed in milliseconds. In other words, the interval argument represents the milliseconds between polls.

Polling is a good way to keep the data in your UI fresh. By refetching your data every 5,000 milliseconds (or 5 seconds, for example) you may effectively emulate realtime data without needing to build up a realtime backend.

If you call data.startPolling when your query is already polling then the current polling process will be cancelled and a new process will be started with the interval you specified.

You may also use

If you set your interval to 0 then that means no polling instead of executing a request every JavaScript event loop tick.

Example:

1
class MyComponent extends Component {
2
  componentDidMount() {
3
    // In this specific case you may want to use `options.pollInterval` instead.
4
    this.props.data.startPolling(1000);
5
  }
6

7
  render() {
8
    // ...
9
  }
10
}
11

12
export default graphql(gql`query MyComponentQuery { ... }`)(MyComponent);

data.stopPolling()

By calling this function you will stop any current polling process. Your query will not start polling again until you call data.startPolling.

Example:

1
class MyComponent extends Component {
2
  render() {
3
    return (
4
      <div>
5
        <button
6
          onClick={() => {
7
            this.props.data.startPolling(1000);
8
          }}
9
        >
10
          Start Polling
11
        </button>
12
        <button
13
          onClick={() => {
14
            this.props.data.stopPolling();
15
          }}
16
        >
17
          Stop Polling
18
        </button>
19
      </div>
20
    );
21
  }
22
}
23

24
export default graphql(gql`query MyComponentQuery  { ... }`)(MyComponent);

data.updateQuery(updaterFn)

This function allows you to update the data for your query outside of the context of any mutation, subscription, or fetch. This function only takes a single argument which will be another function. The argument function has the following signature:

1
(previousResult, { variables }) => nextResult

The first argument will be the data for your query that currently exists in the store, and you are expected to return a new data object with the same shape. That new data object will be written to the store and any components tracking that data will be updated reactively.

The second argument is an object with a single property, variables. The variables property allows you to see what variables were used when reading the previousResult from the store.

This method will not update anything on the server. It will only update data in your client cache and if you reload your JavaScript environment then your update will disappear.

Example:

1
data.updateQuery(previousResult => ({
2
  ...previousResult,
3
  count: previousResult.count + 1,
4
}));

config.options

An object or function that returns an object of options that are used to configure how the query is fetched and updated.

If config.options is a function then it will take the component’s props as its first argument.

The options available for use in this object depend on the operation type you pass in as the first argument to graphql(). The references below will document which options are available when your operation is a query. To see what other options are available for different operations, see the generic documentation for

Example:

1
export default graphql(gql`query MyQuery { ... }`, {
2
  options: {
3
    // Options go here.
4
  },
5
})(MyComponent);

1
export default graphql(gql`query MyQuery { ... }`, {
2
  options: props => ({
3
    // Options are computed from `props` here.
4
  }),
5
})(MyComponent);

options.variables

The variables that will be used when executing the query operation. These variables should correspond with the variables that your query definition accepts. If you define config.options as a function then you may compute your variables from your props.

Example:

1
export default graphql(
2
  gql`
3
  query MyQuery ($width: Int!, $height: Int!) {
4
    ...
5
  }
6
`,
7
  {
8
    options: props => ({
9
      variables: {
10
        width: props.size,
11
        height: props.size,
12
      },
13
    }),
14
  },
15
)(MyComponent);

options.fetchPolicy

The fetch policy is an option that allows you to specify how you want your component to interact with the Apollo Client cache. By default, your component will try to read from the cache first, and if the full data for your query is in the cache then Apollo simply returns the data from the cache. If the full data for your query is not in the cache then Apollo will execute your request using your network interface. By changing this option you can change this behavior.

For a list of supported fetch policies, see

Example:

1
export default graphql(gql`query MyQuery { ... }`, {
2
  options: { fetchPolicy: 'cache-and-network' },
3
})(MyComponent);

options.errorPolicy

The error policy is an option which allows you to specify how you want your component to handle errors that can happen when fetching data from GraphQL. There are two types of errors that can happen during your request; a runtime error on the client or server which results in no data, or some GraphQL errors which may be delivered alongside actual data. In order to control how your UI interacts with these errors, you can use the error policy to tell Apollo when you want to know about GraphQL Errors or not!

Valid errorPolicy values are:

• none: This is the default value where we treat GraphQL errors as runtime errors. Apollo will discard any data that came back with the request and render your component with an error prop.
• ignore: Much like none, this causes Apollo to ignore any data from your server, but it also won't update your UI aside from setting the loading state back to false.
• all: Selecting all means you want to be notified any time there are any GraphQL errors. It will render your component with any data from the request and any errors with their information. It is particularly helpful for server side rendering so your UI always shows something

Example:

1
export default graphql(gql`query MyQuery { ... }`, {
2
  options: { errorPolicy: 'all' },
3
})(MyComponent);

options.pollInterval

The interval in milliseconds at which you want to start polling. Whenever that number of milliseconds elapses your query will be executed using the network interface and another execution will be scheduled using the configured number of milliseconds.

This option will start polling your query immediately when the component mounts. If you want to start and stop polling dynamically then you may use

If you set options.pollInterval to 0 then that means no polling instead of executing a request every JavaScript event loop tick.

Example:

1
export default graphql(gql`query MyQuery { ... }`, {
2
  options: { pollInterval: 5000 },
3
})(MyComponent);

options.notifyOnNetworkStatusChange

Whether or not updates to the network status or network error should trigger re-rendering of your component.

The default value is false.

Example:

1
export default graphql(gql`query MyQuery { ... }`, {
2
  options: { notifyOnNetworkStatusChange: true },
3
})(MyComponent);

options.context

With the flexibility and power of

partialRefetch

If true, perform a query refetch if the query result is marked as being partial, and the returned data is reset to an empty Object by the Apollo Client QueryManager (due to a cache miss).

The default value is false for backwards-compatibility's sake, but should be changed to true for most use-cases.

Example:

1
export default graphql(gql`query MyQuery { ... }`, {
2
  options: { partialRefetch: true },
3
})(MyComponent);

graphql() options for mutations

props.mutate

The higher order component created when you pass a mutation to graphql() will provide your component with a single prop named mutate. Unlike the data prop which you get when you pass a query to graphql(), mutate is a function.

The mutate function will actually execute your mutation using the network interface therefore mutating your data. The mutate function will also then update your cache in ways you define.

To learn more about how mutations work, be sure to check out the

The mutate function accepts the same options that

The reason the mutate function accepts the same options is that it will use the options from

Example:

1
function MyComponent({ mutate }) {
2
  return (
3
    <button
4
      onClick={() => {
5
        mutate({
6
          variables: { foo: 42 },
7
        });
8
      }}
9
    >
10
      Mutate
11
    </button>
12
  );
13
}
14

15
export default graphql(gql`mutation MyMutation { ... }`)(MyComponent);

config.options

An object or function that returns an object of options that are used to configure how the query is fetched and updated.

If config.options is a function then it will take the component’s props as its first argument.

The options available for use in this object depend on the operation type you pass in as the first argument to graphql(). The references below will document which options are available when your operation is a mutation. To see what other options are available for different operations, see the generic documentation for

The properties accepted in this options object may also be accepted by the

Example:

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export default graphql(gql`mutation MyMutation { ... }`, {
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  options: {
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    // Options go here.
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  },
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})(MyComponent);

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export default graphql(gql`mutation MyMutation { ... }`, {
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  options: props => ({
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    // Options are computed from `props` here.
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  }),
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})(MyComponent);

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function MyComponent({ mutate }) {
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  return (
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    <button
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      onClick={() => {
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        mutate({
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          // Options are component from `props` and component state here.
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        });
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      }}
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    >
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      Mutate
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    </button>
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  );
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}
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export default graphql(gql`mutation MyMutation { ... }`)(MyComponent);

options.variables

The variables which will be used to execute the mutation operation. These variables should correspond to the variables that your mutation definition accepts. If you define config.options as a function, or you pass variables into the

Example:

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export default graphql(
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  gql`
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  mutation MyMutation ($foo: String!, $bar: String!) {
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    ...
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  }
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`,
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  {
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    options: props => ({
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      variables: {
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        foo: props.foo,
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        bar: props.bar,
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      },
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    }),
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  },
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)(MyComponent);

options.optimisticResponse

Often when you mutate data it is fairly easy to predict what the response of the mutation will be before asking your server. The optimistic response option allows you to make your mutations feel faster by simulating the result of your mutation in your UI before the mutation actually finishes.

To learn more about the benefits of optimistic data and how to use it be sure to read the recipe on

This optimistic response will be used with

Example:

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function MyComponent({ newText, mutate }) {
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  return (
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    <button
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      onClick={() => {
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        mutate({
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          variables: {
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            text: newText,
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          },
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          // The optimistic response has all of the fields that are included in
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          // the GraphQL mutation document below.
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          optimisticResponse: {
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            createTodo: {
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              id: -1, // A temporary id. The server decides the real id.
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              text: newText,
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              completed: false,
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            },
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          },
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        });
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      }}
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    >
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      Add Todo
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    </button>
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  );
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}
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export default graphql(gql`
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  mutation CreateTodo ($text: String!) {
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    createTodo(text: $text) {
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      id
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      text
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      completed
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    }
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  }
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`)(MyComponent);

options.update

This option allows you to update your store based on your mutation’s result. By default Apollo Client will update all of the overlapping nodes in your store. Anything that shares the same id as returned by the dataIdFromObject you defined will be updated with the new fields from your mutation results. However, sometimes this alone is not sufficient. Sometimes you may want to update your cache in a way that is dependent on the data currently in your cache. For these updates you may use an options.update function.

options.update takes two arguments. The first is an instance of a DataProxy object which has some methods which will allow you to interact with the data in your store. The second is the response from your mutation - either the optimistic response, or the actual response returned by your server (see the mutation result described in the

In order to change the data in your store call methods on your DataProxy instance like