OAuth2 Refresh Token Handler (oauth2/refresh-access-token.ts)

Builds and sends a refresh token request to obtain new access tokens, supporting custom auth, extra parameters, and resource scopes for reusable OAuth2 flows.

// Source: https://github.com/better-auth/better-auth | License: MIT | Copyright 2024 - present, Bereket Engida
// Provided via justclaw.it.com; keep this notice with the code.
import type { AwaitableFunction } from "../types";
import type { OAuth2Tokens, ProviderOptions } from "./oauth-provider";
import { fetchRefusingRedirects } from "./reject-redirects";
import type {
	TokenEndpointAuth,
	TokenEndpointSecretAuthentication,
} from "./token-endpoint-auth";
import { applyTokenEndpointAuth } from "./token-endpoint-auth";
import { parseScopeField } from "./utils";

interface RefreshAccessTokenRequestInput {
	refreshToken: string;
	options: AwaitableFunction<Partial<ProviderOptions>>;
	authentication?: TokenEndpointSecretAuthentication | undefined;
	tokenEndpointAuth?: TokenEndpointAuth | und

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