# ApolloQuery
You can use the ApolloQuery
(or apollo-query
) component to have watched Apollo queries directly in your template.
After reading this page, see the API Reference for all the possible options.
# Query gql tag
This is the recommended way of using the ApolloQuery
component. It uses the same syntax with the gql
tag like in the other examples:
<template>
<ApolloQuery
:query="gql => gql`
query MyHelloQuery ($name: String!) {
hello (name: $name)
}
`"
:variables="{ name }"
>
<!-- TODO -->
</ApolloQuery>
</template>
We are passing a function to the query
prop that gets the gql
tag as argument, so we can write the GraphQL document directly.
The above example also features variables
passed to the query using the prop with the same name.
Inside the default slot of ApolloQuery
, you can access various slot data about the watched query, like the result
object:
<template v-slot="{ result: { loading, error, data } }">
<!-- Loading -->
<div v-if="loading" class="loading apollo">Loading...</div>
<!-- Error -->
<div v-else-if="error" class="error apollo">An error occurred</div>
<!-- Result -->
<div v-else-if="data" class="result apollo">{{ data.hello }}</div>
<!-- No result -->
<div v-else class="no-result apollo">No result :(</div>
</template>
Here is the complete example component:
<script>
export default {
data () {
return {
name: 'Anne'
}
}
}
</script>
<template>
<div>
<input v-model="name" placeholder="Enter your name">
<ApolloQuery
:query="gql => gql`
query MyHelloQuery ($name: String!) {
hello (name: $name)
}
`"
:variables="{ name }"
>
<template v-slot="{ result: { loading, error, data } }">
<!-- Loading -->
<div v-if="loading" class="loading apollo">Loading...</div>
<!-- Error -->
<div v-else-if="error" class="error apollo">An error occurred</div>
<!-- Result -->
<div v-else-if="data" class="result apollo">{{ data.hello }}</div>
<!-- No result -->
<div v-else class="no-result apollo">No result :(</div>
</template>
</ApolloQuery>
</div>
</template>
# Tag setup
If you are not using vue-cli-plugin-apollo (opens new window) (v0.20.0+
), you need to configure vue-loader (opens new window) to transpile the string template tag. vue-loader
uses Bublé (opens new window) under-the-hood to transpile code inside component templates. We need to add the dangerousTaggedTemplateString
transform to Bublé for gql
to work. For example, with Vue CLI:
// vue.config.js
module.exports = {
chainWebpack: config => {
config.module
.rule('vue')
.use('vue-loader')
.loader('vue-loader')
.tap(options => {
options.transpileOptions = {
transforms: {
dangerousTaggedTemplateString: true,
},
}
return options
})
}
}
In a raw Webpack configuration, it would look like this:
module.exports = {
module: {
rules: [
{
test: /\.vue$/,
use: [
{
loader: 'vue-loader',
options: {
transpileOptions: {
transforms: {
dangerousTaggedTemplateString: true
}
}
}
}
]
},
/* Other rules ... */
]
}
}
# Query with gql files
An alternative way of using the component is by creating separate .gql
files. Those files need pre-processing with graphql-tag (opens new window).
<template>
<ApolloQuery
:query="require('../graphql/HelloWorld.gql')"
:variables="{ name }"
>
<template v-slot="{ result: { loading, error, data } }">
<!-- Loading -->
<div v-if="loading" class="loading apollo">Loading...</div>
<!-- Error -->
<div v-else-if="error" class="error apollo">An error occurred</div>
<!-- Result -->
<div v-else-if="data" class="result apollo">{{ data.hello }}</div>
<!-- No result -->
<div v-else class="no-result apollo">No result :(</div>
</template>
</ApolloQuery>
</template>
# Query operations
You can access the smart query object with the query
slot prop. Here is an example component paginating data with fetchMore
:
<template>
<ApolloQuery
:query="/* query */"
:variables="{
limit: $options.pageSize
}"
v-slot="{ result: { loading, error, data }, query }"
>
<!-- Display data here -->
<button v-if="hasMore" @click="loadMore(query)">Load more</button>
</ApolloQuery>
</template>
<script>
export default {
pageSize: 10,
data: {
return {
page: 1,
hasMore: true
}
},
methods: {
async loadMore (query) {
await query.fetchMore({
variables: {
offset: this.page++ * this.$options.pageSize
},
updateQuery: (prev, { fetchMoreResult }) => {
if (!fetchMoreResult || fetchMoreResult.product.length === 0) {
this.hasMore = false
return prev
}
return Object.assign({}, prev, {
product: [...prev.product, ...fetchMoreResult.product]
})
}
})
}
}
}
</script>
See the API reference for all possible smart query methods.
# Using fragments
Fragments are useful to share parts of GraphQL documents in other documents to retrieve the same data consistently and also to not copy-paste code.
Let's say we have this GetMessages
query with a messages
field that is an array of Message
objects:
query GetMessages {
messages {
id
user {
id
name
}
text
created
}
}
We want to extract all the fields in messages
of the Message
type into a fragment, so we can reuse it elsewhere.
First import the gql
tag in the component:
import gql from 'graphql-tag'
Then, inside the component definition, declare a new fragments
object:
export default {
fragments: {
/** TODO */
}
}
Here is what the message
fragment, which is applied on the Message
type, looks like:
fragment message on Message {
id
user {
id
name
}
text
created
}
We can use the gql
tag just like we do for queries:
export default {
fragments: {
message: gql`
fragment message on Message {
id
user {
id
name
}
text
created
}
`
}
}
Inside our component, we can now access the fragment with this.$options.fragments.message
. To use the fragment in our GetMessages
query, we need to use the GraphQL ...
spread operator and also put the fragment alongside the query:
gql`
query GetMessages {
messages {
...message
}
}
${$options.fragments.message}
`
Which will effectively produce this GraphQL document (that you can try on the GraphQL playground of your API):
query GetMessages {
messages {
...message
}
}
fragment message on Message {
id
user {
id
name
}
text
created
}
So what's happening here? GraphQL will find the ...
operator where we usually select fields in the messages
field inside our query. The ...
operator is followed by the name of the fragment, message
, which then looked up the whole GraphQL document. Here we have correctly defined the fragment, so it's found just under the query. Finally, GraphQL will copy all the fragment content and replace ...message
with it.
In the end, we obtain the final query:
query GetMessages {
messages {
id
user {
id
name
}
text
created
}
}
fragment message on Message {
id
user {
id
name
}
text
created
}
Here is the full example component:
<!-- MessageList.vue -->
<script>
import gql from 'graphql-tag'
export default {
fragments: {
message: gql`
fragment message on Message {
id
user {
id
name
}
text
created
}
`
}
}
</script>
<template>
<ApolloQuery
:query="gql => gql`
query GetMessages {
messages {
...message
}
}
${$options.fragments.message}
`"
>
<!-- Content... -->
</ApolloQuery>
</template>
# Reusing the fragment
Now we can retrieve the message
fragment in another component:
<!-- MessageForm.vue -->
<script>
import gql from 'graphql-tag'
import MessageList from './MessageList.vue'
export default {
methods: {
async sendMessage () {
await this.$apollo.mutate({
mutation: gql`
mutation SendMessage ($input: SendMessageInput!) {
addMessage (input: $input) {
newMessage {
...message
}
}
}
${MessageList.fragments.message}
`,
variables: {
/* variables here */
},
/* other options here */
})
}
}
}
</script>