react-async

Wrapper for react to support asynchronous calls

Installation

Run the following command

npm install @ohm-vision/react-async

Usage

There are several effects offered depending on your needs

useAsync

This is will likely be your best friend and the method you use the most.

It will fire your async function when a dependency has changed and return a Tuple indicating if the method is still loading

Important note:

This method does not wrap anything in a try-catch block, error management is YOUR responsibility

Example

import { useAsync } from "@ohm-vision/react-async"

export function MyAwesomeComponent(props) {
    const [ loading, result ] = useAsync(async (abortSignal: AbortSignal) => {
        // just in case we don't want to use the `useFetch`
        // ie. we have our own API classes, or are calling a third-party sdk
        const result = await fetch("http://example.com", {
            method: "GET",
            signal: abortSignal
        });

        return await result.json();
    }, [ props.dep1 ], () => {
        console.log("I was unloaded");
    });

    if (loading) {
        // todo: show a skeleton component
        return <>Loading...</>;
    }

    // todo: do something with the result
    // note: `result` will be undefined until the first load is complete
}

useEffectAsync

This is the core async effect with nothing special

Important note:

This method does not wrap anything in a try-catch block, error management is YOUR responsibility

Example

import { useEffectAsync } from "@ohm-vision/react-async"

export function MyAwesomeComponent(props) {
    const loading = useEffectAsync(async (signal: AbortSignal) => {
        // some special call

        // all processing is handled here - you manage everything

        // the AbortSignal will automatically be called when the component is unmounted
    }, [ props.dep1 ], () => {
        console.log("I was unloaded");
    });

}

useFetch

This is an extension to the useAsync which wraps the standard fetch call using what I consider to be a good standard for handling the operation

Used for loading data on the client

Important note:

Unlike other methods, this hook will capture the error response and return it to you as the third tuple (triple/triplet?)

This is done because unlike the other methods, there is less control over the function lifecycle when using this hook.

props (param 1)

This accepts all properties of the native fetch command and adds the following:

• url: string | URL | RequestInfo - endpoint to fetch
• responseType: "raw" | "arrayBuffer" | "blob" | "formData" | "text" | "json" - indicates how to process the successful response
  • When raw is used, the original Response object is returned
  • All other responses, will call the appropriate method to read the body and return a mutated response object

Example

import { useFetch } from "@ohm-vision/react-async"

export function MyAwesomeComponent(props) {
    const [ loading, { body }, error ] = useFetch({
        url: "https://example.com",
        responseType: "text",
    }, [ props.dep1 ], () => {
        console.log("I was unloaded");
    });

    if (loading) {
        return <>Loading...</>
    }

    if (error) {
        return <>ERROR: {error.toString()}</>;
    }

    // todo: do something with the body
}

useMemoAsync

This is an extension to the useEffectAsync which attempts to operate similarly to React's native useMemo function

Used for firing asynchronous calls which return a result, could be a good alternative if you want to do something special.

This method will just return the result or the previous value if an async call is still running

Important note:

This method does not wrap anything in a try-catch block, error management is YOUR responsibility

Example

import { useMemoAsync } from "@ohm-vision/react-async"

export function MyAwesomeComponent(props) {
    const result = useMemoAsync(async (abortSignal: AbortSignal) => {
        // just in case we don't want to use the `useFetch`
        // ie. we have our own API classes, or are calling a third-party sdk
        const result = await fetch("http://example.com", {
            method: "GET",
            signal: abortSignal
        });

        return await result.json();
    }, [ props.dep1 ], () => {
        console.log("I was unloaded");
    });

    // todo: do something with the result
    // note: `result` will be undefined until the first load is complete
}

Contact Me

Ohm Vision, Inc