This repository was created to help react developers optimize their codebase and figure out a way to write less boilerplate code. Some of the hooks and utils in this repo were created by me, others was borrowed from blogs, community resources, and also from the other developers i worked with. My goal is just to accumulate knowledge and share it with others. Please note, not all hooks and utils here are in their original form, sometimes I made some changes to fit my goals or modified them based on what works better in my experience. So if you find any mistakes, please let me know.

useStickyState

There are situations when we need to persist state between sessions, which obviously leads us to deal with localSorage values. To serve this purpose i like to use hook called useStickyState:

✏️ Code

const useStickyState = <T>(defaultValue: T, key: string) => {
  const [value, setValue] = React.useState<T>(() => {
    const stickyValue = window.localStorage.getItem(key);

    return stickyValue !== null ? JSON.parse(stickyValue) : defaultValue;
  });

  React.useEffect(() => {
    window.localStorage.setItem(key, JSON.stringify(value));
  }, [key, value]);

  return [value, setValue] as const;
};

🧑‍💻 Usage example

const SomeComponent() {
  const [person, setPerson] = useStickyState('Some Key', 'some value');
}

It's used just like React.useState, except it takes two arguments: a default value, and a key. The second argument, key, will be used as the localStorage key. It's important that each useStickyState instance uses a unique value.

💡 Quick typescript note

The hook simply infers the type of the value passed in, but when i use it in my projects i prefer strict typization to view all the values that might be stored in the localStorage.

/** All possible keys for usePersistedState */
enum Keys {
    ZoneAlert = 'disable_zone_alert_for_date',
}

/** All possible key: value pairs for usePersistedState */
type Entries = {
    [Keys.ZoneAlert]: ZoneAlertDefaultState;
};

const useStickyState = <T extends Entries[Keys], U extends Keys>(defaultValue: T, key: U) => ...

parseError

This sounds familiar, right?

try {
  //some code here
} catch (error) {
  notify({ message: error.message });
}

But if we use typescript, it will yield at us that the error actually has type 'unknown' and we can't access the 'message' property without an additional type check. Utility function parseError gives us an opportunity to handle this case in a simple and secure way:

✏️ Code

type ErrorWithMessage = {
  message: string;
};

type ErrorWithStatus = {
  status: number;
};

function isErrorWithMessage(error: unknown): error is ErrorWithMessage {
  return (
    typeof error === "object" &&
    error !== null &&
    "message" in error &&
    typeof (error as Record<string, unknown>).message === "string"
  );
}

function isErrorWithStatus(error: unknown): error is ErrorWithStatus {
  return (
    typeof error === "object" &&
    error !== null &&
    "status" in error &&
    typeof (error as Record<string, unknown>).status === "number"
  );
}

function toErrorWithMessage(maybeError: unknown): ErrorWithMessage {
  if (isErrorWithMessage(maybeError)) return maybeError;

  if (typeof maybeError === "string" && maybeError) {
    return new Error(maybeError);
  }

  try {
    return new Error(
      maybeError ? JSON.stringify(maybeError) : i18n("error.message-default")
    );
  } catch {
    // fallback in case there's an error stringifying the maybeError
    // like with circular references for example.
    return new Error(String(maybeError));
  }
}

export function getErrorMessage(error: unknown) {
  return toErrorWithMessage(error).message;
}

const WELL_KNOWN_STATUSES_MAP: Record<string, string | undefined> = {
  403: i18n("title.error-403"),
  404: i18n("title.error-404"),
  500: i18n("title.error-500"),
};

export const parseError = (error: unknown) => {
  const status = isErrorWithStatus(error) ? String(error.status) : "500";

  return {
    description: getErrorMessage(error),
    status,
    title:
      WELL_KNOWN_STATUS_KEYSETS_MAP[status] ||
      i18nK("title.error-default") ||
      "",
  };
};

🧑‍💻 Usage example

try {
  //some code here
} catch (error) {
  const { title, description, status } = parseError(error);

  notify({ title, description, status });
}

Now we can be sure that our 'catch' case handles properly because we use type safe function, which covers all failure scenario and prevents your code from unexpected collapse.

useFilters

I think every frontend engineer at least once created a page with entities filters. Hook 'useFilters' can help you perform this typical task with ease.

✏️ Code

interface UseFiltersParams<T extends {}, F extends {}, O extends {}> {
  initialData: T[];
  initialFilters: F;
  filterFn: (data: T[], filter: F, options?: O) => T[];
  options?: O;
}

const useFilters = <T extends {}, F extends {}, O extends {}>(
  params: UseFiltersParams<T, F, O>
) => {
  const { initialData, initialFilters, filterFn, options } = params;

  const [filter, setFilter] = React.useState(initialFilters);
  const [filteredValue, setFilteredValue] = React.useState(initialData);

  React.useEffect(() => {
    setFilteredValue(filterFn(initialData, filter, options));
  }, [initialData, filterFn, filter, options]);

  const onFilterChange = React.useCallback(
    (currentFilter: F) => {
      setFilteredValue(filterFn(initialData, currentFilter, options));
    },
    [initialData, filterFn, options]
  );

  const handleChange = React.useCallback(
    (currentFilter: F) => {
      setFilter(currentFilter);
      onFilterChange(currentFilter);
    },
    [onFilterChange]
  );

  return [filteredValue, filter, handleChange] as const;
};

🧑‍💻 Usage example

const INITIAL_FILTERS: RuleFilter = {
  tagOrDescriptionOrId: "",
  ruleGroup: "",
  ruleType: "",
};

const getFilteredRules = (rules: Rule[], filters: RuleFilter) => {
  const {
    tagOrDescriptionOrId,
    ruleGroup,
    ruleType,
    paranoiaLevel,
    activeState,
    blocking,
  } = filters;

  let result = rules;

  if (ruleGroup) {
    result = filterByField(result, "ruleGroup", ruleGroup);
  }

  if (ruleType) {
    result = filterByField(result, "ruleType", ruleType);
  }

  if (tagOrDescriptionOrId) {
    result = filterBySomeFields(
      result,
      ["description", "id", "tags"],
      tagOrDescriptionOrId
    );
  }

  return result;
};

const [filteredRules, filter, onFilterChange] = useFilters({
  initialData: rules,
  initialFilters: INITIAL_FILTERS_BASE,
  filterFn: getFilteredRules,
});

The hook can easily be upgraded to persist filters to the url string,i just showed you the basic version here.

useElementSize

If you want to get the target element size, i would suggest you to take a look at 'useElementSize'

✏️ Code

import React from "react";

import round from "lodash/round";
import throttle from "lodash/throttle";

const RESIZE_THROTTLE = 16;
const ROUND_PRESICION = 2;

export interface UseElementSizeResult {
  width: number;
  height: number;
}

export function useElementSize<T extends HTMLElement = HTMLDivElement>(
  ref: React.MutableRefObject<T | null> | null,
  // can be used, when it is needed to force reassign observer to element
  // in order to get correct measures. might be related to below
  // https://github.com/WICG/resize-observer/issues/65
  key?: string
) {
  const [size, setSize] = React.useState<UseElementSizeResult>({
    width: 0,
    height: 0,
  });

  React.useLayoutEffect(() => {
    if (!ref?.current) {
      return undefined;
    }

    const handleResize: ResizeObserverCallback = (entries) => {
      if (!Array.isArray(entries)) {
        return;
      }

      const entry = entries[0];

      if (entry?.borderBoxSize) {
        const borderBoxSize = entry.borderBoxSize[0]
          ? entry.borderBoxSize[0]
          : (entry.borderBoxSize as unknown as ResizeObserverSize);
        // ...but old versions of Firefox treat it as a single item
        // https://github.com/mdn/dom-examples/blob/main/resize-observer/resize-observer-text.html#L88

        setSize({
          width: round(borderBoxSize.inlineSize, ROUND_PRESICION),
          height: round(borderBoxSize.blockSize, ROUND_PRESICION),
        });
      } else {
        const target = entry.target as HTMLElement;

        setSize({
          width: round(target.offsetWidth, ROUND_PRESICION),
          height: round(target.offsetHeight, ROUND_PRESICION),
        });
      }
    };

    const observer = new ResizeObserver(
      throttle(handleResize, RESIZE_THROTTLE)
    );

    observer.observe(ref.current);

    return () => {
      observer.disconnect();
    };
  }, [ref, key]);

  return size;
}

🧑‍💻 Usage example

const labelSize = useElementSize(isLabelVisible ? labelRef : null, size);

const startContentSize = useElementSize(
  isStartContentVisible ? startContentRef : null,
  size
);

useDebounce

I think that debounce needs no introduction, it's an indispensable helper on any front-end project, allowing us to do a lot of cool stuff, like preventing unnecessary api calls when user is typing in a search field. Here is a hook implementation:

✏️ Code

export function useDebounce<T>(value: T, delay: number): T {
  const [debounced, setDebounced] = useState(value);

  useEffect(() => {
    const timerId = setTimeout(() => {
      setDebounced(value);
    }, delay);

    return () => {
      clearTimeout(timerId);
    };
  }, [value, delay]);

  return debounced;
}

🧑‍💻 Usage example

const [query, setQuery] = useState(""); // updates without a delay
const debouncedQuery = useDebounce(query, 1000); // updates with a 1 second delay

useToggle

Often when implementing new features we want to toggle something (modals, switchers, etc.), so why don't make this logic reusable?

✏️ Code

const useToggle = (
  initialValue: boolean
): [boolean, (nextValue?: boolean) => void] => {
  const [value, setValue] = useState(initialValue);

  function toggle(nextValue?: boolean) {
    //we can pass an optional argument or the state simply will be changed to the opposite value
    setValue((current) => nextValue ?? !current);
  }

  return [value, toggle];
};

🧑‍💻 Usage example

const [on, toggle] = useToggle(true);

toggle();
//or
toggle(true);