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node_modules/matrix-js-sdk/lib/pollingCachedValue.d.ts

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+import { type Logger } from "./logger.ts";
+/**
+ * How to fetch and cache a given value, as passed to {@link PollingCachedValue}.
+ */
+export interface PollingCachedValueOptions<ValueType> {
+    /** The name of the cached value (for tracing/logs). */
+    name: string;
+    /** The logger to derive this value's child logger from. */
+    logger: Logger;
+    /** Fetches a fresh value. Rejections are retried according to the retry policy. */
+    fetch: () => Promise<ValueType>;
+    /**
+     * The default time-to-live before the value gets refreshed, overridable per run
+     * via {@link PollingCachedValue.start}.
+     * If undefined the value never expires; use {@link PollingCachedValue.refresh} to clear the cache.
+     */
+    ttlMillis?: number;
+    /** Called when a new value is cached. Use to emit changes if needed. */
+    onValueCached?: (value: ValueType) => void;
+    /**
+     * Determines whether a non-transient error should be cached.
+     * By default errors are not cached, i.e. the next attempt retries the fetch.
+     */
+    shouldCacheError?: (error: unknown) => boolean;
+}
+/**
+ * Defines a generic mechanism to fetch and cache a value, refreshing it periodically.
+ */
+export declare class PollingCachedValue<ValueType> {
+    private readonly opts;
+    private cached?;
+    private fetchPromise?;
+    private ttlTimeoutHandle?;
+    private isStopped;
+    private ttlMillis?;
+    private readonly logger;
+    /**
+     * Build a generic mechanism allowing to fetch and cache a given value.
+     * @param opts - Describes what to fetch and how to cache it, see {@link PollingCachedValueOptions}.
+     */
+    constructor(opts: PollingCachedValueOptions<ValueType>);
+    /**
+     * Gets the cached value if any.
+     */
+    get(): ValueType | undefined;
+    /**
+     * Ensures that the value was fetched once before getting the actual cached value.
+     */
+    wait(): Promise<ValueType | undefined>;
+    /**
+     * Call this as early as possible and when the value can already be fetched.
+     * @param ttlMillis - The time-to-live before the value gets refreshed, overriding the one
+     *     given at construction. If omitted the configured default is kept.
+     */
+    start(ttlMillis?: number): void;
+    /**
+     * Call when the client is stopped, or when the cached value is no longer needed.
+     */
+    stop(): void;
+    /**
+     * Force to refresh.
+     * @throws
+     */
+    refresh(): Promise<ValueType | undefined>;
+    /**
+     * Internal fetch method
+     * @param force - if set to true will force a fetch of the value even if a fetch is already in progress.
+     * @private
+     */
+    private doFetch;
+    /**
+     * Gracefully handle transient error retries, respect retry_after_millis for rate limits.
+     * @private
+     */
+    private fetchWithRetryPolicy;
+}
+//# sourceMappingURL=pollingCachedValue.d.ts.map