React Native AsyncStorage Implementation

storage.js

import { AsyncStorage } from 'react-native' // change this to @react-native-community/async-storage when this issue is solved https://github.com/react-native-community/react-native-async-storage/issues/14

export default Storage = {
    async getItem(itemKey) {
        let result = {
            key: itemKey,
            value: null,
            error: null,
        }

        try {
            const item = await AsyncStorage.getItem(itemKey)
            if (item !== null) {
                result.value = JSON.parse(item)
            }
        } catch (error) {
            result.error = error
        }

        return result
    },
    async setItem(itemKey, itemValue) {
        let result = {
            key: itemKey,
            value: null,
            error: null,
        }
        try {
            await AsyncStorage.setItem(itemKey, JSON.stringify(itemValue))
            result.value = itemValue
        } catch (error) {
            result.error = error
        }
        return result
    },
    async removeItem(itemKey) {
        let result = {
            key: itemKey,
            value: null,
            error: null,
        }
        try {
            result.value = await AsyncStorage.getItem(itemKey)
            await AsyncStorage.removeItem(itemKey)
        } catch (error) {
            result.error = error
        }
        return result
    },
    async concatArray(itemKey, itemValue) {
        let result = {
            key: itemKey,
            value: null,
            error: null,
        }

        try {
            let oldArray = await AsyncStorage.getItem(itemKey)
            let array = oldArray ? JSON.parse(oldArray) : []
            array.push(itemValue)
            await AsyncStorage.setItem(itemKey, JSON.stringify(array))
            result.value = array
        } catch (error) {
            result.error = error
        }

        return result
    },
    async updateArrayAtIndex(itemKey, itemValue, itemIndex) {
        let result = {
            key: itemKey,
            value: null,
            error: null,
        }

        try {
            let oldArray = await AsyncStorage.getItem(itemKey)
            let array = oldArray ? JSON.parse(oldArray) : []
            array[itemIndex] = itemValue
            await AsyncStorage.setItem(itemKey, JSON.stringify(array))
            result.value = array
        } catch (error) {
            result.error = error
        }

        return result
    },
    async removeArrayIndex(itemKey, itemIndex) {
        let result = {
            key: itemKey,
            value: null,
            error: null,
        }

        try {
            let oldArray = await AsyncStorage.getItem(itemKey)
            let array = oldArray ?  JSON.parse(oldArray) : []
            array = array.filter((x, i) => i != itemIndex)
            await AsyncStorage.setItem(itemKey, JSON.stringify(array))
            result.value = array
        } catch (error) {
            result.error = error
        }

        return result
    }
}