Medplum

// SPDX-FileCopyrightText: Copyright Orangebot, Inc. and Medplum contributors // SPDX-License-Identifier: Apache-2.0 import { stringify } from './utils'; export interface IClientStorage { getInitPromise?(): Promise<void>; clear(): void; getString(key: string): string | undefined; setString(key: string, value: string | undefined): void; getObject<T>(key: string): T | undefined; setObject<T>(key: string, value: T): void; makeKey(key: string): string; } /** * The ClientStorage class is a utility class for storing strings and objects. * * When using MedplumClient in the browser, it will be backed by browser localStorage. * * When Using MedplumClient in the server, it will be backed by the MemoryStorage class. For example, the Medplum CLI uses `FileSystemStorage`. */ export class ClientStorage implements IClientStorage { private readonly storage: Storage; private readonly prefix: string = ''; constructor(storage?: Storage, prefix = '') { this.storage = storage ?? globalThis.localStorage ?? new MemoryStorage(); this.prefix = prefix; } makeKey(key: string): string { return this.prefix + key; } clear(): void { // We only care about checking the keys for localStorage when a prefix is present if (this.storage === globalThis.localStorage && this.prefix) { Object.keys(this.storage) .filter((key) => key.startsWith(this.prefix)) .forEach((key) => { this.storage.removeItem(key); }); } else { // If not localStorage, then just clear out the whole storage this.storage.clear(); } } getString(key: string): string | undefined { return this.storage.getItem(this.makeKey(key)) ?? undefined; } setString(key: string, value: string | undefined): void { if (value) { this.storage.setItem(this.makeKey(key), value); } else { this.storage.removeItem(this.makeKey(key)); } } getObject<T>(key: string): T | undefined { const str = this.getString(key); return str ? (JSON.parse(str) as T) : undefined; } setObject<T>(key: string, value: T): void { this.setString(key, value ? stringify(value) : undefined); } } /** * The MemoryStorage class is a minimal in-memory implementation of the Storage interface. */ export class MemoryStorage implements Storage { private readonly data: Map<string, string>; constructor() { this.data = new Map<string, string>(); } /** * Returns the number of key/value pairs. * @returns The number of key/value pairs. */ get length(): number { return this.data.size; } /** * Removes all key/value pairs, if there are any. */ clear(): void { this.data.clear(); } /** * Returns the current value associated with the given key, or null if the given key does not exist. * @param key - The specified storage key. * @returns The current value associated with the given key, or null if the given key does not exist. */ getItem(key: string): string | null { return this.data.get(key) ?? null; } /** * Sets the value of the pair identified by key to value, creating a new key/value pair if none existed for key previously. * @param key - The storage key. * @param value - The new value. */ setItem(key: string, value: string | null): void { if (value) { this.data.set(key, value); } else { this.data.delete(key); } } /** * Removes the key/value pair with the given key, if a key/value pair with the given key exists. * @param key - The storage key. */ removeItem(key: string): void { this.data.delete(key); } /** * Returns the name of the nth key, or null if n is greater than or equal to the number of key/value pairs. * @param index - The numeric index. * @returns The nth key. */ key(index: number): string | null { return Array.from(this.data.keys())[index]; } } /** * The MockAsyncClientStorage class is a mock implementation of the ClientStorage class. * This can be used for testing async initialization of the MedplumClient. */ export class MockAsyncClientStorage extends ClientStorage implements IClientStorage { private initialized: boolean; private readonly initPromise: Promise<void>; private initResolve: () => void = () => undefined; constructor() { super(); this.initialized = false; this.initPromise = new Promise((resolve) => { this.initResolve = resolve; }); } setInitialized(): void { if (!this.initialized) { this.initResolve(); this.initialized = true; } } getInitPromise(): Promise<void> { return this.initPromise; } get isInitialized(): boolean { return this.initialized; } }