The useQuery React hook is the primary API for executing queries in an Apollo application. To run a query within a React component, call useQuery and pass it a GraphQL query string. When your component renders, useQuery returns an object from Apollo Client that contains loading, error, and data properties you can use to render your UI. The useQuery hook returns an object with three useful properties that we use in our app: indicates whether the query has completed and results have been returned. is an object that contains any errors that the operation has thrown. contains the results of the query after it has completed. Again, this example is similar to the useQuery-based component above, but it differs after the rendering is completed. Because this component relies on a button click to fire a mutation, we use Testing Library's user-event library to simulate a click with its click method. Jul 19, 2020 · This solution is a nice balance between smooth experience that users can see the cached result first without waiting and accurate result, which then updates to the UI. Nov 5, 2020 · I have these 3 functions that need to run in order. However, since the first function has a loop in it, the 2nd and 3rd functions are finishing before the data from the 1st function is available. ... Jun 27, 2021 · 2 Answers. useQuery ("fetchData", fetchData, { onSuccess: (data) => { console.log ("Get data!"); console.log (data); } }); As simple it could be. Thanks! The onSuccess callback function is called only when the data has been retrieved from the query. Carefully notice that this data is not the one that you're de-structuring from the useQuery ... The useQuery hook. The useQuery hook returns an object with three useful properties that we use in our app: indicates whether the query has completed and results have been returned. is an object that contains any errors that the operation has thrown. contains the results of the query after it has completed. To set in our query, we declare them ... Aug 23, 2021 · variables will be the variables object passed in useQuery (eg, { name: "Fido" } in this example). We have the option here to return dummy data based on what variables are passed. Or, as we are doing in our test, we can ignore the return value and assert with expect that our spy was called with the variables we are expecting. Oct 16, 2020 · read from localstorage, build variables for fetch (offset, limit, ...) fetch with variables; when filters or search change, refetch with modified variables; also save the modified variables to localstorage; My question is: should I use useQuery or useLazyQuery for this purpose. With useQuery, I may could do: Nov 27, 2020 · Writing Our First Reactive Variable #. Here’s what a reactive variable looks like: import { makeVar } from '@apollo/client'; const myReactiveVariable = makeVar (/** An initial value can be passed in here.**/) The makeVar is imported from Apollo Client and is used to declare our a reactive variable. Jan 5, 2021 · I have a Higher Order Component and it accepts a prop variable input called "name". Inside HOC, I'm passing "name" as the input to useQuery. If the name's value changes, useQuery hits the backend API and fetches new results but if the value remains the same, there is no network call made by useQuery. HOC gets re-rendered but no n/w call. Nov 5, 2020 · I have these 3 functions that need to run in order. However, since the first function has a loop in it, the 2nd and 3rd functions are finishing before the data from the 1st function is available. ... Optional for the useQuery hook, because the query can be provided as the first parameter to the hook. Required for the Query component. variables { [key: string]: any } An object containing all of the GraphQL variable s your query requires to execute. Each key in the object corresponds to a variable name, and that key's value corresponds to the ... Jul 14, 2022 · React Query’s useQuery(query, fn) is a Hook that fetches data based on the query passed to it and then stores the data in its parent variable. A query, in this case, consists of a unique key and an asynchronous function that is acted upon. Server-side rendering (SSR) is a performance optimization for modern web apps. It enables you to render your app's initial state to raw HTML and CSS on the server before serving it to a browser. This means users don't have to wait for their browser to download and initialize React (or Angular, Vue, etc.) before content is available: Browser ... I set up my own project and was experiencing the same issue when using useQuery. UPDATE: After adding an item, useQuery seems to work fine. Intended outcome: value of loading changes to false when data is available. Actual outcome: value of loading never updates to false. Version Feb 13, 2021 · 1 Answer. You don’t need an extra way to distribute your data, like react context. Just call useQuery with the same key wherever you need to, and react query will do the rest. It is best to abstract that away in a custom hook. refetch should only be used if you want to refetch with the exact same parameters. Aug 26, 2020 · i need to make one of two queries based on the result of another request to a third party, is there a way to tell Apollo to wait for that request to finish and return the appropriate query for Apollo ? or should i just make the request and add the appropriate query manually to Apollo when i get the results ? Dec 31, 2020 · Addition: If you want to await for resolving mutate, you can wrap the whole call in a Promise and resolve it in onSuccess (or onSuccess / onSettle) like this: await new Promise ( (resolve) => { mutatePostInfo.mutate (value, { onSuccess: () => resolve () }) }); – Froxx Feb 12, 2022 · React Query dependent queries. We can leverage the enabled property to make queries dependent on a variable. This will tell React Query if this query should be enabled or not, and it can accept anything that calculates to a boolean. const { isIdle, data } = useQuery('your-key', yourQueryFn, { enabled: conditionIsTrue, }); May 31, 2023 · My logic is intended as follows: In useEffect. get {id} from the router. trigger getUserFromId (id) with that id. setUser () with db response. Run the query. get user from state and pass it into variables: {} for query. run the query. I think that my problem is that the useEffect is running after my useQuery so the user i am trying to get from ... Again, this example is similar to the useQuery-based component above, but it differs after the rendering is completed. Because this component relies on a button click to fire a mutation, we use Testing Library's user-event library to simulate a click with its click method. Mar 10, 2020 · I want the data returned from useQuery to be undefined when the variables change. Reasoning is that if the variables for the query change, loading is set to true, but data remains set to the data from the previous query with old variables. Actual outcome: data is set to the previous variables data while the next query (with new variables) is in ... Feb 13, 2021 · 1 Answer. You don’t need an extra way to distribute your data, like react context. Just call useQuery with the same key wherever you need to, and react query will do the rest. It is best to abstract that away in a custom hook. refetch should only be used if you want to refetch with the exact same parameters. May 31, 2020 · 14. I need to call a query when submit button is pressed and then handle the response. I need something like this: const [checkEmail] = useLazyQuery (CHECK_EMAIL) const handleSubmit = async () => { const res = await checkEmail ( { variables: { email: values.email }}) console.log (res) // handle response } Try #1: Nov 5, 2020 · I have these 3 functions that need to run in order. However, since the first function has a loop in it, the 2nd and 3rd functions are finishing before the data from the 1st function is available. ... Jul 14, 2022 · React Query’s useQuery(query, fn) is a Hook that fetches data based on the query passed to it and then stores the data in its parent variable. A query, in this case, consists of a unique key and an asynchronous function that is acted upon. May 24, 2021 · The useQuery hook accepts a lot more parameters and returns a lot more variables, which have been documented in the React Query docs. The example above is meant to demonstrate the minimum setup ... Nov 28, 2022 · 1 It because: setParticipant change state asynchronously, useEffect invokes after render actually happend so even if data.participant is not empty, participant is, until next render phase You could change to this: const ProfilePage = ( { id }) => { //... if (loading || !participant) { return <div>Loading</div>; } //... } Share Aug 27, 2019 · let client = new ApolloClient ( { ssrMode: true, link: authLink.concat (httpLink), cache: new InMemoryCache (), }); To clarify when I say 'block rendering' I mean hold off on SSR finalising until the server has the data to send the user so that the tag will appear immediately with the loaded page. reactjs. graphql. Aug 20, 2019 · I think something like this would work - you will need to create the initial state with useState, could be empty array and then onComplete in the useQuery would setTranscationsData... it is triggered every render when state or props change. Could of course add an inital state inside useState which insn't an empty array. Nov 28, 2022 · 1 It because: setParticipant change state asynchronously, useEffect invokes after render actually happend so even if data.participant is not empty, participant is, until next render phase You could change to this: const ProfilePage = ( { id }) => { //... if (loading || !participant) { return <div>Loading</div>; } //... } Share The useQuery hook runs automatically on component render, whereas the useMutation hook returns a mutate function needed to trigger the mutation The useQuery hook is used to send queries, whereas the useMutation hook is used to send mutations The useQuery hook returns an array, whereas the useMutation hook returns an object Only the useQuery hook accepts variables The useQuery hook returns an ... Jan 26, 2020 · We use graphql-code-generator to generate the introspection file for us. Go to your back-end code, or wherever your graphql.gql file lies, and do: Install GraphQL Code Generator: yarn add graphql yarn add -D @graphql-codegen/cli. Run the initialization wizard: yarn graphql-codegen init. Jun 27, 2021 · 2 Answers. useQuery ("fetchData", fetchData, { onSuccess: (data) => { console.log ("Get data!"); console.log (data); } }); As simple it could be. Thanks! The onSuccess callback function is called only when the data has been retrieved from the query. Carefully notice that this data is not the one that you're de-structuring from the useQuery ... A derived boolean from the status variable above, provided for convenience. isSuccess: boolean. A derived boolean from the status variable above, provided for convenience. isError: boolean. A derived boolean from the status variable above, provided for convenience. isLoadingError: boolean. Will be true if the query failed while fetching for the ... Jan 26, 2020 · We use graphql-code-generator to generate the introspection file for us. Go to your back-end code, or wherever your graphql.gql file lies, and do: Install GraphQL Code Generator: yarn add graphql yarn add -D @graphql-codegen/cli. Run the initialization wizard: yarn graphql-codegen init. Mar 19, 2023 · this works, because you can't expect await refetch() to change the data variable in the closure (the result from useQuery). So you have to use the result returned from refetch(). If you only need the query to eventually call refetch, I would use queryClient.fetchQuery instead. – Aug 26, 2020 · i need to make one of two queries based on the result of another request to a third party, is there a way to tell Apollo to wait for that request to finish and return the appropriate query for Apollo ? or should i just make the request and add the appropriate query manually to Apollo when i get the results ? Each one of them will become a reactive object. These reactive queries will be executed automatically, both when the component is mounted, and if/when any variable objects change. Great! Now let's define the graphql query to be used: Open src/graphql-operations/index.ts and add the following code: src/graphql-operations/index.ts Copy Jan 26, 2020 · We use graphql-code-generator to generate the introspection file for us. Go to your back-end code, or wherever your graphql.gql file lies, and do: Install GraphQL Code Generator: yarn add graphql yarn add -D @graphql-codegen/cli. Run the initialization wizard: yarn graphql-codegen init. Jul 29, 2020 · The Apollo platform is an implementation of GraphQL that transfers data between the cloud (the server) to the UI of your app. When you use Apollo Client, all of the logic for retrieving data, tracking, loading, and updating the UI is encapsulated by the useQuery hook (as in the case of React). Hence, data fetching is declarative. Unlike useQuery, useMutation doesn't execute its operation automatically on render. Instead, you call this mutate function. An object with field s that represent the current status of the mutation 's execution (data, loading, etc.) This object is similar to the object returned by the useQuery hook. For details, see Result. Example Nov 27, 2020 · Writing Our First Reactive Variable #. Here’s what a reactive variable looks like: import { makeVar } from '@apollo/client'; const myReactiveVariable = makeVar (/** An initial value can be passed in here.**/) The makeVar is imported from Apollo Client and is used to declare our a reactive variable. The useQuery hook returns an object with three useful properties that we use in our app: indicates whether the query has completed and results have been returned. is an object that contains any errors that the operation has thrown. contains the results of the query after it has completed. Apollo Client allows you to make local modifications to your GraphQL data by updating the cache, but sometimes it's more straightforward to update your client-side GraphQL data by refetching queries from the server. In theory, you could refetch every active query after a client-side update, but you can save time and network bandwidth by ... Sep 12, 2022 · Set the `enabled` property in the useQuery call. Once the user clicked on that button we will update the fetchPosts state value, which will trigger the component to re-render and the useQuery hook will execute and fetch the data in case the fetchPosts value is true. function Example() { const [fetchPosts, setFetchPosts] = useState(false); const ... Jul 19, 2020 · This solution is a nice balance between smooth experience that users can see the cached result first without waiting and accurate result, which then updates to the UI. Aug 10, 2020 · the query qUsuario is: query qUsuario ($user:ID!) { user (id:$user) { email, firstName, lastName, } } but in the first time i got the follow error: [GraphQL error]: Variable "$user" of required type "ID!" was not provided. and then in few milliseconds later, the query works! Mar 10, 2021 · In the last post, we did a basic web service request using the useQuery hook. This post will expand this example and make a second request that requires data from the first request. Our requirement. At the moment, our React component requests the people resource in the Star Wars API and displays the character’s name. The useQuery hook updates and executes queries whenever its inputs, like the query or variables change, but in some cases we may find that we need to programmatically trigger a new query. This is the purpose of the executeQuery method which is a method on the result object that useQuery returns. Sep 10, 2021 · If you have a mutation that updates the title of your blog post, and the backend returns the complete blog post as a response, you can update the query cache directly via setQueryData: update-from-mutation-response. 1const useUpdateTitle = (id) => {. 2 const queryClient = useQueryClient() 3. 4 return useMutation({. Feb 13, 2021 · 1 Answer. You don’t need an extra way to distribute your data, like react context. Just call useQuery with the same key wherever you need to, and react query will do the rest. It is best to abstract that away in a custom hook. refetch should only be used if you want to refetch with the exact same parameters. May 31, 2020 · 14. I need to call a query when submit button is pressed and then handle the response. I need something like this: const [checkEmail] = useLazyQuery (CHECK_EMAIL) const handleSubmit = async () => { const res = await checkEmail ( { variables: { email: values.email }}) console.log (res) // handle response } Try #1: Once again, we'll pass our query to the useQuery hook. This time, we also need to pass the corresponding launch's launchId to the query as a variable. We'll use React Router's useParams hook to access the launchId from our current URL. Apollo Client allows you to make local modifications to your GraphQL data by updating the cache, but sometimes it's more straightforward to update your client-side GraphQL data by refetching queries from the server. In theory, you could refetch every active query after a client-side update, but you can save time and network bandwidth by ... Feb 12, 2022 · React Query dependent queries. We can leverage the enabled property to make queries dependent on a variable. This will tell React Query if this query should be enabled or not, and it can accept anything that calculates to a boolean. const { isIdle, data } = useQuery('your-key', yourQueryFn, { enabled: conditionIsTrue, }); Sep 12, 2022 · Set the `enabled` property in the useQuery call. Once the user clicked on that button we will update the fetchPosts state value, which will trigger the component to re-render and the useQuery hook will execute and fetch the data in case the fetchPosts value is true. function Example() { const [fetchPosts, setFetchPosts] = useState(false); const ... Mar 19, 2023 · this works, because you can't expect await refetch() to change the data variable in the closure (the result from useQuery). So you have to use the result returned from refetch(). If you only need the query to eventually call refetch, I would use queryClient.fetchQuery instead. – Mar 14, 2019 · Normally I put [all, my, query, variables] into the useQuery to avoid multiple runs when other state is changing. @pak11273 I don't understand why you would need another state (useState). Using the data from useQuery should suffice, no? I needed the onComplete to trigger another query which needed data from the first query. Mar 19, 2023 · this works, because you can't expect await refetch() to change the data variable in the closure (the result from useQuery). So you have to use the result returned from refetch(). If you only need the query to eventually call refetch, I would use queryClient.fetchQuery instead. – Mar 19, 2023 · this works, because you can't expect await refetch() to change the data variable in the closure (the result from useQuery). So you have to use the result returned from refetch(). If you only need the query to eventually call refetch, I would use queryClient.fetchQuery instead. – Once again, we'll pass our query to the useQuery hook. This time, we also need to pass the corresponding launch's launchId to the query as a variable. We'll use React Router's useParams hook to access the launchId from our current URL. The problem is that the value state stays null but when I refresh the component (I go into VSCode, I do a random modification and I save) it works. Here's the state and the function : export const pokemonFilters: PokemonFilters = [ { game: `yellow`, version: `yellow`, min: 0, max: 152, }, (a few more objects like that in the array) const [game ... I have a code below where in I want to finish doSomethingFirst() before proceeding with the rest of the code: async doSomething() { const response = await doSomethingFirst(); // get the response Nov 5, 2020 · I have these 3 functions that need to run in order. However, since the first function has a loop in it, the 2nd and 3rd functions are finishing before the data from the 1st function is available. ... Mar 24, 2021 · Using GraphQLClient allows us to set the API key on each request. To get all blog posts from the API, we use the useGetPosts function. The useQuery hook expects a key ( get-posts) and a GraphQL query. The hook can receive more options, but for this example, we just need these two. Once the fetch is done, we return the data. Mar 14, 2023 · A query is an asynchronous data source bound to a unique key. TanStack Query uses the useQuery Hook to get the data. In the example, our useQuery takes two parameters, a unique key for the query and a function that returns a Promise. The useQuery returns the following: isLoading: In the fetching state May 13, 2020 · Local State Management improvements with Cache Policies and Reactive Variables. My personal favorite new features about Apollo Client 3 are Cache Policies and Reactive Variables. Cache Policies Cache Policies introduce a new way to modify what the cache returns before reads and writes to the cache. It introduces cleaner patterns for setting ... Nov 5, 2020 · I have these 3 functions that need to run in order. However, since the first function has a loop in it, the 2nd and 3rd functions are finishing before the data from the 1st function is available. ... Mar 10, 2020 · I want the data returned from useQuery to be undefined when the variables change. Reasoning is that if the variables for the query change, loading is set to true, but data remains set to the data from the previous query with old variables. Actual outcome: data is set to the previous variables data while the next query (with new variables) is in ... Feb 7, 2021 · 1. Another thing to consider is the default configuration of you useQuery () hook which is provided by the QueryClient. For example rerendering on window focus is a default setting, which causes the hook to refetch and therefore rerender on every window focus (for example when clicking on devtools and click back into the DOM. The first parameter to useQuery is a string and this is how the hook knows what to cache when data is returned. You want to make sure this is unique. Another optional way of creating this “cache key”, is to pass it an array of strings. react-query will combine them into one string. As mentioned, you’ll want to make the cache key unique ... Nov 14, 2020 · This can be achived using useEffect ( () => {// send the request}, [criteria]) Because, useEffect ensures that the request will send to server only if the setCriteria is finished. But, I am using react-query library. so that, it is not allowed to use useQuery inside useEffect. As A result, the request is send to server before it the setState is ... Apollo Client allows you to make local modifications to your GraphQL data by updating the cache, but sometimes it's more straightforward to update your client-side GraphQL data by refetching queries from the server. In theory, you could refetch every active query after a client-side update, but you can save time and network bandwidth by ... Jul 19, 2020 · This solution is a nice balance between smooth experience that users can see the cached result first without waiting and accurate result, which then updates to the UI. May 31, 2020 · 5 Answers Sorted by: 19 This works for me: const { refetch } = useQuery (CHECK_EMAIL, { skip: !values.email }) const handleSubmit = async () => { const res = await refetch ( { variables: { email: values.email }}) console.log (res) } Share Follow answered Dec 15, 2020 at 16:05 kurtko 1,978 4 30 46 2 some suggestion: it would be better to build the key as an array to be able to use the fuzzy invalidation react-query provides. something like: ["posts", postId]; also, you don't need to call refetch after calling setPostId. setting the id will trigger a re-render, which will change the key. changing the key will automatically trigger a refetch. Sep 10, 2021 · If you have a mutation that updates the title of your blog post, and the backend returns the complete blog post as a response, you can update the query cache directly via setQueryData: update-from-mutation-response. 1const useUpdateTitle = (id) => {. 2 const queryClient = useQueryClient() 3. 4 return useMutation({. .