HomeOfThings - Node Utils: various utilities and common types
npm install @homeofthings/node-utils






- AsyncContext: little wrapper around AsyncLocalStorage providing default value
``Typescript`
asyncContext = new AsyncContext(defaultContext);
...
asyncContext.set(newContext)
...
currentContext = asyncContext.get();
- ConfigService: singleton service based on node-config
`Typescript`
configService = new ConfigService({ configDirectory: 'path/to/config' });
then use one of the methods provided by the ConfigService:
`TypeScript
export declare class ConfigService {
readonly configDirectory: string;
readonly environment: string;
constructor(_opts: ConfigOptions);
getConfig(key: string): object | undefined;
reloadConfig(): void;
getString(key: string, defaultValue: string): string;
getNumber(key: string, defaultValue: number): number;
getBoolean(key: string, defaultValue: boolean): boolean;
getObject(key: string, defaultValue: object): object;
// resolve path relative to config-directory
getPath(key: string, defaultValue: string): string;
getOptionalString(key: string): string | undefined;
getOptionalNumber(key: string): number | undefined;
getOptionalBoolean(key: string): boolean | undefined;
getOptionalObject(key: string): object | undefined;
// resolve path relative to config-directory
getOptionalPath(key: string): string | undefined;
}
`
reload on SIGHUP:
`TypeScript`
process.on('SIGHUP', () => ConfigService.getInstance().reloadConfig());
- LruCache: LRU cache
`Typescript
cache = new LruCache
cache.set(id, userSession); // add this to the cache and mark it as least recently used
...
cache.get(anotherId); // if it is available in the cache it will be marked as least recently used
`
- sequentialize: run Promises in sequence
`Typescript`
await sequentialize(item.map(() => doWork(item)));
- wait: wait until a condition is true or timed out
`Typescript`
await wait(condition); // polls until condition is true
await wait(condition, 1000); // polls until condition is true or timed out after 1000ms
- WritableStrings: a Writable for writing to a string array
- quoteArgs and quoteArg`: quote arguments for better readability (e.g. for logging)