Apollo and GraphQL for Vue.js

Integrates apollo in your Vue components with declarative queries. Compatible with Vue 1.0+ and 2.0+

Apollo "hello world" example app

More vue-apollo examples

Apollo graphql server example

Howto on Medium

Table of contents

• Installation
• Configuration
• Usage in components
• Queries
  • Simple query
  • Query with parameters
  • Option function
  • Reactive query definition
  • Reactive parameters
  • Skipping the query
  • Advanced options
  • Reactive Query Example
• Mutations
• Subscriptions
  • Skipping the subscription
• Pagination with fetchMore

Installation

npm install --save vue-apollo apollo-client

Configuration

import Vue from 'vue';
import ApolloClient, { createNetworkInterface } from 'apollo-client';
import VueApollo from 'vue-apollo';

// Create the apollo client
const apolloClient = new ApolloClient({
  networkInterface: createNetworkInterface({
    uri: 'http://localhost:3020/graphql',
    transportBatching: true,
  }),
});

// Install the vue plugin
Vue.use(VueApollo, {
  apolloClient,
});

// Your Vue app is now Apollo-enabled!

Usage in components

To declare apollo queries in your Vue component, add an apollo object :

new Vue({
    apollo: {
        // Apollo specific options
    },
});

You can access the apollo-client instance with this.$apollo.client in all your vue components.

Queries

In the apollo object, add an attribute for each property you want to feed with the result of an Apollo query.

Simple query

Use gql to write your GraphQL queries:

import gql from 'graphql-tag';

Put the gql query directly as the value:

apollo: {
  // Simple query that will update the 'hello' vue property
  hello: gql`{hello}`,
},

You can then access the query with this.$apollo.queries.<name>.

You can initialize the property in your vue component's data hook:

data () {
  return {
    // Initialize your apollo data
    hello: '',
  },
},

Or with the ES2015 syntax:

data: () => ({
  // Initialize your apollo data
  hello: '',
}),

Server-side, add the corresponding schema and resolver:

export const schema = `
type Query {
  hello: String
}

schema {
  query: Query
}
`;

export const resolvers = {
  Query: {
    hello(root, args, context) {
      return "Hello world!";
    },
  },
};

For more info, visit the apollo doc.

You can then use your property as usual in your vue component:

<template>
  <div class="apollo">
    <h3>Hello</h3>
    <p>
      {{hello}}
    </p>
  </div>
</template>

Query with parameters

You can add variables (read parameters) to your gql query by declaring query and variables in an object:

// Apollo-specific options
apollo: {
  // Query with parameters
  ping: {
    // gql query
    query: gql`query PingMessage($message: String!) {
      ping(message: $message)
    }`,
    // Static parameters
    variables: {
      message: 'Meow',
    },
  },
},

You can use the apollo watchQuery options in the object, like:

• forceFetch
• fragments
• returnPartialData
• pollInterval
• ...

See the apollo doc for more details.

For example, you could add the forceFetch apollo option like this:

apollo: {
  // Query with parameters
  ping: {
    query: gql`query PingMessage($message: String!) {
      ping(message: $message)
    }`,
    variables: {
      message: 'Meow'
    },
    // Additional options here
    forceFetch: true,
  },
},

Again, you can initialize your property in your vue component:

data () {
  return {
    // Initialize your apollo data
    ping: '',
  };
},

Or with the ES2015 syntax:

data: () => ({
  // Initialize your apollo data
  ping: '',
}),

Server-side, add the corresponding schema and resolver:

export const schema = `
type Query {
  ping(message: String!): String
}

schema {
  query: Query
}
`;

export const resolvers = {
  Query: {
    ping(root, { message }, context) {
      return `Answering ${message}`;
    },
  },
};

And then use it in your vue component:

<template>
  <div class="apollo">
    <h3>Ping</h3>
    <p>
      {{ping}}
    </p>
  </div>
</template>

Option function

You can use a function to initialize the key:

// Apollo-specific options
apollo: {
  // Query with parameters
  ping () {
    // This will called one when the component is created
    // It must return the option object
    return {
      // gql query
      query: gql`query PingMessage($message: String!) {
        ping(message: $message)
      }`,
      // Static parameters
      variables: {
        message: 'Meow',
      },
    }
  },
},

This will called once when the component is created and it must return the option object.

This also works for subscriptions.

Reactive query definition

You can use a function for the query option, that will update the graphql query definition automatically:

// The featured tag can be either a random tag or the last added tag
featuredTag: {
  query () {
    // Here you can access the component instance with 'this'
    if (this.showTag === 'random') {
      return gql`{
        randomTag {
          id
          label
          type
        }
      }`
    } else if (this.showTag === 'last') {
      return gql`{
        lastTag {
          id
          label
          type
        }
      }`
    }
  },
  // We need this to assign the value of the 'featuredTag' component property
  update: data => data.randomTag || data.lastTag,
},

This also works for subscriptions.

Reactive parameters

Use a function instead to make the parameters reactive with vue properties:

// Apollo-specific options
apollo: {
  // Query with parameters
  ping: {
    query: gql`query PingMessage($message: String!) {
      ping(message: $message)
    }`,
    // Reactive parameters
    variables() {
      // Use vue reactive properties here
      return {
          message: this.pingInput,
      };
    },
  },
},

This will re-fetch the query each time a parameter changes, for example:

<template>
  <div class="apollo">
    <h3>Ping</h3>
    <input v-model="pingInput" placeholder="Enter a message" />
    <p>
      {{ping}}
    </p>
  </div>
</template>

Skipping the query

If the query is skipped, it will disable it and the result will not be updated anymore. You can use the skip option:

// Apollo-specific options
apollo: {
  tags: {
    // GraphQL Query
    query: gql`query tagList ($type: String!) {
      tags(type: $type) {
        id
        label
      }
    }`,
    // Reactive variables
    variables() {
      return {
        type: this.type,
      };
    },
    // Disable the query
    skip() {
      return this.skipQuery
    },
  },
},

Here, skip will be called automatically when the skipQuery component property changes.

You can also access the query directly and set the skip property:

this.$apollo.quries.tags.skip = true

Advanced options

These are the available advanced options you can use:

• update(data) {return ...} to customize the value that is set in the vue property, for example if the field names don't match.
• result(data) is a hook called when a result is received.
• error(error) is a hook called when there are errors, error being an Apollo error object with either a graphQLErrors property or a networkError property.
• loadingKey will update the component data property you pass as the value. You should initialize this property to 0 in the component data() hook. When the query is loading, this property will be incremented by 1 and as soon as it no longer is, the property will be decremented by 1. That way, the property can represent a counter of currently loading queries.
• watchLoading(isLoading, countModifier) is a hook called when the loading state of the query changes. The countModifier parameter is either equal to 1 when the query is now loading, or -1 when the query is no longer loading.

// Apollo-specific options
apollo: {
  // Advanced query with parameters
  // The 'variables' method is watched by vue
  pingMessage: {
    query: gql`query PingMessage($message: String!) {
      ping(message: $message)
    }`,
    // Reactive parameters
    variables() {
      // Use vue reactive properties here
      return {
          message: this.pingInput,
      };
    },
    // We use a custom update callback because
    // the field names don't match
    // By default, the 'pingMessage' attribute
    // would be used on the 'data' result object
    // Here we know the result is in the 'ping' attribute
    // considering the way the apollo server works
    update(data) {
      console.log(data);
      // The returned value will update
      // the vue property 'pingMessage'
      return data.ping;
    },
    // Optional result hook
    result(data) {
      console.log("We got some result!");
    },
    // Error handling
    error(error) {
      console.error('We\'ve got an error!', error);
    },
    // Loading state
    // loadingKey is the name of the data property
    // that will be incremented when the query is loading
    // and decremented when it no longer is.
    loadingKey: 'loadingQueriesCount',
    // watchLoading will be called whenever the loading state changes
    watchLoading(isLoading, countModifier) {
      // isLoading is a boolean
      // countModifier is either 1 or -1
    },
  },
},

If you use ES2015, you can also write the update like this:

update: data => data.ping

Reactive Query Example

Here is a reactive query example using polling:

// Apollo-specific options
apollo: {
  // 'tags' data property on vue instance
  tags: {
    query: gql`query tagList {
      tags {
        id,
        label
      }
    }`,
    pollInterval: 300, // ms
  },
},

Here is how the server-side looks like:

export const schema = `
type Tag {
  id: Int
  label: String
}

type Query {
  tags: [Tag]
}

schema {
  query: Query
}
`;

// Fake word generator
import casual from 'casual';

// Let's generate some tags
var id = 0;
var tags = [];
for (let i = 0; i < 42; i++) {
  addTag(casual.word);
}

function addTag(label) {
  let t = {
    id: id++,
    label,
  };
  tags.push(t);
  return t;
}

export const resolvers = {
  Query: {
    tags(root, args, context) {
      return tags;
    },
  },
};

Mutations

Mutations are queries that changes your data state on your apollo server. For more info, visit the apollo doc.

methods: {
  addTag() {
    // We save the user input in case of an error
    const newTag = this.newTag;
    // We clear it early to give the UI a snappy feel
    this.newTag = '';
    // Call to the graphql mutation
    this.$apollo.mutate({
      // Query
      mutation: gql`mutation ($label: String!) {
        addTag(label: $label) {
          id
          label
        }
      }`,
      // Parameters
      variables: {
        label: newTag,
      },
      // Update the cache with the result
      // 'tagList' is the name of the query declared before
      // that will be updated with the optimistic response
      // and the result of the mutation
      updateQueries: {
        tagList: (previousQueryResult, { mutationResult }) => {
          // We incorporate any received result (either optimistic or real)
          // into the 'tagList' query we set up earlier
          return {
            tags: [...previousQueryResult.tags, mutationResult.data.addTag],
          };
        },
      },
      // Optimistic UI
      // Will be treated as a 'fake' result as soon as the request is made
      // so that the UI can react quickly and the user be happy
      optimisticResponse: {
        __typename: 'Mutation',
        addTag: {
          __typename: 'Tag',
          id: -1,
          label: newTag,
        },
      },
    }).then((data) => {
      // Result
      console.log(data);
    }).catch((error) => {
      // Error
      console.error(error);
      // We restore the initial user input
      this.newTag = newTag;
    });
  },
},

Server-side:

export const schema = `
type Tag {
  id: Int
  label: String
}

type Query {
  tags: [Tag]
}

type Mutation {
  addTag(label: String!): Tag
}

schema {
  query: Query
  mutation: Mutation
}
`;

// Fake word generator
import faker from 'faker';

// Let's generate some tags
var id = 0;
var tags = [];
for (let i = 0; i < 42; i++) {
  addTag(faker.random.word());
}

function addTag(label) {
  let t = {
    id: id++,
    label,
  };
  tags.push(t);
  return t;
}

export const resolvers = {
  Query: {
    tags(root, args, context) {
      return tags;
    },
  },
  Mutation: {
    addTag(root, { label }, context) {
      console.log(`adding tag '${label}'`);
      return addTag(label);
    },
  },
};

Subscriptions

To make enable the websocket-based subscription, a bit of additional setup is required:

import Vue from 'vue'
import ApolloClient, { createNetworkInterface } from 'apollo-client';
// New Imports
import { Client } from 'subscriptions-transport-ws';
import VueApollo, { addGraphQLSubscriptions } from 'vue-apollo';

// Create the network interface
const networkInterface = createNetworkInterface({
  uri: 'http://localhost:3000/graphql',
  transportBatching: true,
});

// Create the subscription websocket client
const wsClient = new Client('ws://localhost:3030');

// Extend the network interface with the subscription client
const networkInterfaceWithSubscriptions = addGraphQLSubscriptions(
  networkInterface,
  wsClient,
);

// Create the apollo client with the new network interface
const apolloClient = new ApolloClient({
  networkInterface: networkInterfaceWithSubscriptions,
});

// Install the plugin like before
Vue.use(VueApollo, {
  apolloClient,
});

// Your app is now subscription-ready!

import App from './App.vue'

new Vue({
  el: '#app',
  render: h => h(App)
});

Use the $apollo.subscribe() method to subscribe to a GraphQL subscription that will get killed automatically when the component is destroyed:

mounted() {
  const subQuery = gql`subscription tags($type: String!) {
    tagAdded(type: $type) {
      id
      label
      type
    }
  }`;

  const observer = this.$apollo.subscribe({
    query: subQuery,
    variables: {
      type: 'City',
    },
  });

  observer.subscribe({
    next(data) {
      console.log(data);
    },
    error(error) {
      console.error(error);
    },
  });
},

You can declare subscriptions in the apollo option with the subscribe keyword:

apollo: {
  // Subscriptions
  subscribe: {
    // When a tag is added
    tags: {
      query: gql`subscription tags($type: String!) {
        tagAdded(type: $type) {
          id
          label
          type
        }
      }`,
      // Reactive variables
      variables() {
        // This works just like regular queries
        // and will re-subscribe with the right variables
        // each time the values change
        return {
          type: this.type,
        };
      },
      // Result hook
      result(data) {
        console.log(data);
        // Let's update the local data
        this.tags.push(data.tagAdded);
      },
    },
  },
},

You can then access the subscription with this.$apollo.subscriptions.<name>.

For the server implementation, you can take a look at this simple example.

Just like queries, you can declare the subscription with a function, and you can declare the query option with a reactive function.

Skipping the subscription

If the subscription is skipped, it will disable it and it will not be updated anymore. You can use the skip option:

// Apollo-specific options
apollo: {
  // Subscriptions
  subscribe: {
    // When a tag is added
    tags: {
      query: gql`subscription tags($type: String!) {
        tagAdded(type: $type) {
          id
          label
          type
        }
      }`,
      // Reactive variables
      variables() {
        return {
          type: this.type,
        };
      },
      // Result hook
      result(data) {
        // Let's update the local data
        this.tags.push(data.tagAdded);
      },
      // Skip the subscription
      skip() {
        return this.skipSubscription;
      }
    },
  },
},

Here, skip will be called automatically when the skipSubscription component property changes.

You can also access the subscription directly and set the skip property:

this.$apollo.subscriptions.tags.skip = true

Pagination with fetchMore

Use the fetchMore() method on the query:

<template>
  <div id="app">
    <h2>Pagination</h2>
    <div class="tag-list" v-if="tagsPage">
      <div class="tag-list-item" v-for="tag in tagsPage.tags">
        {{ tag.id }} - {{ tag.label }} - {{ tag.type }}
      </div>
      <div class="actions">
        <button v-if="showMoreEnabled" @click="showMore">Show more</button>
      </div>
    </div>
  </div>
</template>

<script>
import gql from 'graphql-tag';

const pageSize = 10;

export default {
  name: 'app',
  data: () => ({
    page: 0,
    showMoreEnabled: true,
  }),
  apollo: {
    // Pages
    tagsPage: {
      // GraphQL Query
      query: gql`query tagsPage ($page: Int!, $pageSize: Int!) {
        tagsPage(page: $page, size: $pageSize) {
          tags {
            id
            label
            type
          }
          hasMore
        }
      }`,
      // Initial variables
      variables: {
        page: 0,
        pageSize,
      },
    },
  },
  methods: {
    showMore() {
      this.page ++;
      // Fetch more data and transform the original result
      this.$apollo.queries.tagsPage.fetchMore({
        // New variables
        variables: {
          page: this.page,
          pageSize,
        },
        // Transform the previous result with new data
        updateQuery: (previousResult, { fetchMoreResult }) => {
          const newTags = fetchMoreResult.data.tagsPage.tags;
          const hasMore = fetchMoreResult.data.tagsPage.hasMore;

          this.showMoreEnabled = hasMore;

          return {
            tagsPage: {
              // Merging the tag list
              tags: [...previousResult.tagsPage.tags, ...newTags],
              hasMore,
            },
          };
        },
      });
    },
  },
};
</script>

Here is a simple example for the server.

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