- public static JSONStringifyWithMapSupport(
- obj: Record<string, unknown> | Record<string, unknown>[],
- space?: number
- ): string {
- return JSON.stringify(
- obj,
- (key, value: Record<string, unknown>) => {
- if (value instanceof Map) {
- return {
- dataType: 'Map',
- value: [...value],
- };
- }
- return value;
- },
- space
- );
- }
+export const isCFEnvironment = (): boolean => {
+ return env.VCAP_APPLICATION != null
+}
+
+export const isNotEmptyString = (value: unknown): value is string => {
+ return typeof value === 'string' && value.trim().length > 0
+}
+
+export const isNotEmptyArray = (value: unknown): value is unknown[] => {
+ return Array.isArray(value) && value.length > 0
+}
+
+export const insertAt = (str: string, subStr: string, pos: number): string =>
+ `${str.slice(0, pos)}${subStr}${str.slice(pos)}`
+
+/**
+ * Computes the retry delay in milliseconds using an exponential backoff algorithm.
+ *
+ * @param retryNumber - the number of retries that have already been attempted
+ * @param delayFactor - the base delay factor in milliseconds
+ * @returns delay in milliseconds
+ */
+export const exponentialDelay = (retryNumber = 0, delayFactor = 100): number => {
+ const delay = Math.pow(2, retryNumber) * delayFactor
+ const randomSum = delay * 0.2 * secureRandom() // 0-20% of the delay
+ return delay + randomSum
+}
+
+/**
+ * Generates a cryptographically secure random number in the [0,1[ range
+ *
+ * @returns A number in the [0,1[ range
+ */
+export const secureRandom = (): number => {
+ return getRandomValues(new Uint32Array(1))[0] / 0x100000000
+}