Keycloak

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import { isRecord } from "../utils/isRecord";
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import { CONTENT_TYPE_HEADER, CONTENT_TYPE_JSON } from "./constants";
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export class ApiError extends Error {}
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export async function parseResponse<T>(response: Response): Promise<T> {
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  const contentType = response.headers.get(CONTENT_TYPE_HEADER);
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  const isJSON = contentType ? contentType.includes(CONTENT_TYPE_JSON) : false;
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  if (!isJSON) {
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    throw new Error(
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      `Expected response to have a JSON content type, got '${contentType}' instead.`,
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    );
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  }
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  const data = await parseJSON(response);
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  if (!response.ok) {
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    throw new ApiError(getErrorMessage(data));
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  }
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  return data as T;
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}
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async function parseJSON(response: Response): Promise<unknown> {
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  try {
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    return await response.json();
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  } catch (error) {
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    throw new Error("Unable to parse response as valid JSON.", {
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      cause: error,
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    });
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  }
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}
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function getErrorMessage(data: unknown): string {
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  if (!isRecord(data)) {
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    throw new Error("Unable to retrieve error message from response.");
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  }
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  const errorKeys = ["error_description", "errorMessage", "error"];
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  for (const key of errorKeys) {
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    const value = data[key];
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    if (typeof value === "string") {
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      return value;
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    }
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  }
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  throw new Error(
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    "Unable to retrieve error message from response, no matching key found.",
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  );
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}
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