Mehedi Hassan Piash | Senior Software Engineer | Android | iOS | KMP | Ktor | Jetpack Compose | React-Native.

September 28, 2024

RTK Query example code in react-native

September 28, 2024 Posted by Mehedi Hassan Piash , , , No comments

RTK Query is one of the best ways to handle data fetching efficiently, a data-fetching and caching tool that comes with the Redux Toolkit. In this article, we’ll walk through an example of using RTK Query in a React Native application.

We’ll demonstrate how to set up RTK Query to fetch movie data from TheMovieDB API and display it in your React Native app.

Movie with RTK Query

Prerequisites

Before we dive in, ensure you have the following set up:
• A React Native project
• Redux Toolkit installed
• RTK Query integrated into your Redux setup
• TheMovieDB API Key (Sign up at themoviedb.org)

Step 1: Install Dependencies
First, you need to install the required dependencies if you haven’t already:

npm install @reduxjs/toolkit react-redux
import { createApi, fetchBaseQuery } from '@reduxjs/toolkit/query/react'
import {Constants} from "../../appconstants/AppConstants.ts";
import {MovieResult} from "../../types/MovieResult.ts";
import {MovieItem} from "../../types/MovieItem.ts";
import {MovieDetail} from "../../types/MovieDetail.ts";
import {CastAndCrew} from "../../types/ArtistAndCrew.ts";
import {ArtistDetail} from "../../types/ArtistDetail.ts";

export const nowPlayingMovieApi = createApi({
reducerPath: 'nowPlayingMovieApi',
baseQuery: fetchBaseQuery({ baseUrl: 'https://api.themoviedb.org/3/' }),
endpoints: (builder) => ({
getNowPlayingMovie: builder.query<MovieItem[], number>({
query: (page) => `movie/now_playing?api_key=${Constants.API_KEY}&language=en-US?page=${page}`,
transformResponse: (response: MovieResult) => response.results
}),
}),
})

export const { useGetNowPlayingMovieQuery } = nowPlayingMovieApi;

export const popularMovieApi = createApi({
reducerPath: 'popularMovieApi',
baseQuery: fetchBaseQuery({ baseUrl: 'https://api.themoviedb.org/3/' }),
endpoints: (builder) => ({
getPopularMovie: builder.query<MovieItem[], number>({
query: (page ) => `movie/popular?api_key=${Constants.API_KEY}&language=en-US?page=${page}`,
transformResponse: (response: MovieResult) => response.results
}),
}),
})


export const {useGetPopularMovieQuery} = popularMovieApi;

export const topRatedMovieApi = createApi({
reducerPath: 'topRatedMovieApi',
baseQuery: fetchBaseQuery({ baseUrl: 'https://api.themoviedb.org/3/' }),
endpoints: (builder) => ({
getTopRatedMovie: builder.query<MovieItem[], number>({
query: (page) => `movie/top_rated?api_key=${Constants.API_KEY}&language=en-US?page=${page}`,
transformResponse: (response: MovieResult) => response.results
}),
}),
})
export const {useGetTopRatedMovieQuery} = topRatedMovieApi;


export const upcomingMovieApi = createApi({
reducerPath: 'upcomingMovieApi',
baseQuery: fetchBaseQuery({ baseUrl: 'https://api.themoviedb.org/3/' }),
endpoints: (builder) => ({
getUpcomingMovie: builder.query<MovieItem[], number>({
query: (page) => `movie/upcoming?api_key=${Constants.API_KEY}&language=en-US?page=${page}`,
transformResponse: (response: MovieResult) => response.results
}),
}),
})

export const {useGetUpcomingMovieQuery} = upcomingMovieApi;

export const movieDetailApi = createApi({
reducerPath: 'movieDetailApi',
baseQuery: fetchBaseQuery({ baseUrl: 'https://api.themoviedb.org/3/' }),
endpoints: (builder) => ({
getMovieDetail: builder.query<MovieDetail, number>({
query: (movieId) => `movie/${movieId}?api_key=${Constants.API_KEY}&language=en-US`,
transformResponse: (response: MovieDetail) => response
}),
}),
})

export const {useGetMovieDetailQuery} = movieDetailApi;


export const similarMovieApi = createApi({
reducerPath: 'similarMovieApi',
baseQuery: fetchBaseQuery({ baseUrl: 'https://api.themoviedb.org/3/' }),
endpoints: (builder) => ({
getSimilarMovie: builder.query<MovieItem[], number>({
query: (movieId) => `movie/${movieId}/recommendations?api_key=${Constants.API_KEY}&language=en-US`,
transformResponse: (response: MovieResult) => response.results
}),
}),
})
export const {useGetSimilarMovieQuery} = similarMovieApi;

export const artistAndCrewApi = createApi({
reducerPath: 'artistAndCrewApi',
baseQuery: fetchBaseQuery({ baseUrl: 'https://api.themoviedb.org/3/' }),
endpoints: (builder) => ({
getArtistAndCrew: builder.query<CastAndCrew, number>({
query: (movieId) => `movie/${movieId}/credits?api_key=${Constants.API_KEY}&language=en-US`,
transformResponse: (response: CastAndCrew) => response
}),
}),
})

export const {useGetArtistAndCrewQuery} = artistAndCrewApi;

export const artistDetailApi = createApi({
reducerPath: 'artistDetailApi',
baseQuery: fetchBaseQuery({ baseUrl: 'https://api.themoviedb.org/3/' }),
endpoints: (builder) => ({
getAristDetail: builder.query<ArtistDetail, number>({
query: (personId) => `person/${personId}?api_key=${Constants.API_KEY}&language=en-US`,
transformResponse: (response: ArtistDetail) => response
}),
}),
})

export const {useGetAristDetailQuery} = artistDetailApi;
import {configureStore} from '@reduxjs/toolkit'
import createSagaMiddleware from 'redux-saga';
import rootSaga from './sagas';
import logger from 'redux-logger';
import {
artistAndCrewApi,
artistDetailApi,
movieDetailApi,
nowPlayingMovieApi,
popularMovieApi,
similarMovieApi,
topRatedMovieApi,
upcomingMovieApi
} from './query/RTKQuery.ts'
import {setupListeners} from "@reduxjs/toolkit/query";

const sagaMiddleware = createSagaMiddleware();
const middleware = [sagaMiddleware];

const configurationAppStore = () => {
const store = configureStore({
reducer: {
[nowPlayingMovieApi.reducerPath]: nowPlayingMovieApi.reducer,
[popularMovieApi.reducerPath]: popularMovieApi.reducer,
[topRatedMovieApi.reducerPath]: topRatedMovieApi.reducer,
[upcomingMovieApi.reducerPath]: upcomingMovieApi.reducer,
[movieDetailApi.reducerPath]: movieDetailApi.reducer,
[similarMovieApi.reducerPath]: similarMovieApi.reducer,
[artistAndCrewApi.reducerPath]: artistAndCrewApi.reducer,
[artistDetailApi.reducerPath]: artistDetailApi.reducer,
},
middleware: (getDefaultMiddleware) => getDefaultMiddleware().concat([...middleware, logger,
nowPlayingMovieApi.middleware,
popularMovieApi.middleware,
topRatedMovieApi.middleware,
upcomingMovieApi.middleware,
movieDetailApi.middleware,
similarMovieApi.middleware,
artistAndCrewApi.middleware,
artistDetailApi.middleware
]),
devTools: process.env.NODE_ENV === 'development'
})
setupListeners(store.dispatch)
sagaMiddleware.run(rootSaga);
return store
}
export default configurationAppStore

Types

import {MovieItem} from "./MovieItem";
import {Dates} from "./Dates";

export interface MovieResult {
dates: Dates
page: number
results: MovieItem[]
total_pages: number
total_results: number
}
export interface MovieItem {
adult: boolean
backdrop_path: string
genre_ids: number[]
id: number
original_language: string
original_title: string
overview: string
popularity: number
poster_path: string
release_date: string
title: string
video: boolean
vote_average: number
vote_count: number
}
export interface Dates {
maximum: string
minimum: string
}

MovieComponent.tsx

import React, {useState} from 'react';
import {FlatList, Image, View, TouchableOpacity, ImageBackground} from "react-native";
import styles from "./MovieListStyle";
import {Constants} from "../../appconstants/AppConstants";
import {MovieItem} from "../../types/MovieItem";

interface MovieItemProps {
movies: Array<MovieItem>;
onPress: (item: MovieItem) => void;
loadMoreData: () => void
}

const MovieComponent = (props: MovieItemProps) => {
const {movies, onPress, loadMoreData} = props;
const [isLoading, setIsLoading] = useState(true)
const movieItem = ({item}: { item: MovieItem }) => {
return (<TouchableOpacity style={styles.movieItemContainer} onPress={() => onPress(item)}>
<ImageBackground
imageStyle={{borderRadius: 18}}
source={isLoading ? require('../../assets/placeholder.jpeg') : {uri: `${Constants.IMAGE_URL}${item.poster_path}`}}
>
<Image
style={styles.imageView}
source={{
uri: `${Constants.IMAGE_URL}${item.poster_path}`,
}}
onLoadEnd={() => {
setIsLoading(false)
}}
/>
</ImageBackground>
</TouchableOpacity>)
};

return (<View style={styles.mainView}>
<FlatList
style={styles.flatListContainer}
data={movies}
renderItem={movieItem}
numColumns={2}
keyExtractor={(item, index) => index.toString()}
onEndReachedThreshold={0.5}
onEndReached={loadMoreData}
/>
</View>);
}

export default MovieComponent

Home.tsx

import React, {useEffect, useState} from 'react';
import Loading from '../../components/loading/Loading';
import MovieComponent from '../../components/movielist/MovieComponent.tsx';
import {View} from 'react-native';
import styles from './HomeStyle'
import {useGetNowPlayingMovieQuery} from "../../redux/query/RTKQuery.ts";
import {useNavigation} from "@react-navigation/native";
import {MovieItem} from "../../types/MovieItem.ts";


const Home = () => {
const navigation = useNavigation();
const [page, setPage] = useState(1);
const [movies, setMovies] = useState<Array<MovieItem>>([]);
const {data, error, isLoading, isFetching} = useGetNowPlayingMovieQuery(page)
useEffect(() => {
if (data && page > 1) {
setMovies((prevMovies) => [...prevMovies, ...data]);
}else {
setMovies(data ?? []);
}
}, [page, data?.length]);

const loadMoreMovies = () => {
if (!isFetching && !isLoading && !error) {
setPage( page + 1);
}
};

if (isLoading) return <Loading/>;

return (<View style={styles.mainView}>
<MovieComponent
movies={movies}
onPress={(item) => navigation.navigate('MovieDetail', {movieId: item.id})}
loadMoreData={loadMoreMovies}/>
</View>);
}
export default Home;

GitHub: https://github.com/piashcse/react-native-movie
Medium: https://piashcse.medium.com/rtk-query-example-code-in-react-native-e9a0bd402d8f

July 28, 2024

Ktor Client in Kotlin Multiplatform

July 28, 2024 Posted by Mehedi Hassan Piash , , No comments

 

Kotlin Multiplatform (KMP) allows you to write code that can be shared across multiple platforms, including Android, iOS, desktop and the web. One of the libraries that make KMP even more powerful is Ktor, a framework for building asynchronous servers and clients in connected systems. In this blog post, we’ll walk through setting up a Ktor client in a KMP project and making a sample HTTP request.

ktor client

Setting Up the Ktor Client

First, let’s look at the code snippet that configures the Ktor client:

val client = HttpClient {
defaultRequest {
url {
takeFrom("https://api.themoviedb.org/") // Base url
parameters.append("api_key", "59cd6896d8432")
}
}
expectSuccess = true
install(HttpTimeout) {
val timeout = 30000L
connectTimeoutMillis = timeout
requestTimeoutMillis = timeout
socketTimeoutMillis = timeout
}
install(Logging) {
logger = Logger.DEFAULT
level = LogLevel.HEADERS
logger = object : Logger {
override fun log(message: String) {
println(message)
}
}
}
install(ContentNegotiation) {
json(Json {
ignoreUnknownKeys = true
})
}
}

Let’s break down what each part of this configuration does.

Default Request Configuration

The defaultRequest block sets up default parameters for all requests made by this client:

defaultRequest {
url {
takeFrom("https://api.themoviedb.org/") // Base url
parameters.append("api_key", "59cd6896d8432")
}
}

Here, we’re specifying a base URL and appending an API key to every request. This is useful for APIs that require authentication or other constant query parameters.

Timeout Configuration

Next, we configure the timeouts for the client:

install(HttpTimeout) {
val timeout = 30000L
connectTimeoutMillis = timeout
requestTimeoutMillis = timeout
socketTimeoutMillis = timeout
}

We set a 30-second timeout for connecting, requesting, and socket operations. This ensures that our client doesn’t hang indefinitely.

Logging Configuration

The Logging feature helps us log HTTP requests and responses:

install(Logging) {
logger = Logger.DEFAULT
level = LogLevel.HEADERS
logger = object : Logger {
override fun log(message: String) {
println(message)
}
}
}

Here, we log the headers of the requests and responses. The custom logger prints these logs to the console.

Content Negotiation

Finally, we configure content negotiation to handle JSON data:

install(ContentNegotiation) {
json(Json {
ignoreUnknownKeys = true
})
}

This tells the client to use JSON for content negotiation and to ignore unknown keys in the JSON response, making the client more resilient to changes in the API.

Using the Ktor Client

Once the client is configured, you can use it to make HTTP requests. Here’s an example of making a GET request to fetch data for a specific person:

suspend fun fetchPersonData(personId: String): Person {
return client.get {
url {
encodedPath = "3/person/$personId"
}
}.body()
}

In this function, we make a GET request to the /3/person/{personId} endpoint. The encodedPath specifies the endpoint, and the personId is dynamically included in the URL. The body() function is used to parse the response into a Person object.

Example Usage

You can call the fetchPersonData function in a coroutine to get the data for a specific person:

fun main() = runBlocking {
val personId = "12345"
val personData = fetchPersonData(personId)
println(personData)
}

In this example, we use runBlocking to start a coroutine, fetch the data for a person with ID 12345, and print the result.

Conclusion

Configuring a Ktor client in a Kotlin Multiplatform project is straightforward and highly customizable. By setting up default requests, timeouts, logging, and content negotiation, you can ensure your HTTP client is robust and efficient. Making requests and handling responses is seamless, allowing you to build powerful and responsive applications. Happy coding!

Ref: https://piashcse.medium.com/ktor-client-in-kotlin-multiplatform-27e6ac59ae01