DeleteCache function for MattMarshEvents API

MattMarshEventsApi-DeleteCache.cs

public static class DeleteCache
{
    private static readonly HttpClient HttpClient = new HttpClient();

    [FunctionName("DeleteEventsCache")]
    public static async Task<IActionResult> Run(
        [HttpTrigger(AuthorizationLevel.Anonymous, "delete", Route = "events/cache")] HttpRequest req,
        ILogger log)
    {
        var zoneId = Environment.GetEnvironmentVariable("CloudflareZoneId");
        var authEmail = Environment.GetEnvironmentVariable("CloudflareAuthEmail");
        var authKey = Environment.GetEnvironmentVariable("CloudflareAuthKey"); //this is in KeyVault

        var cachedUrls = new[]{
            "https://api.mattmarshevents.co.uk/events",
            "https://api.mattmarshevents.co.uk/events/",
        };

        var url = $"https://api.cloudflare.com/client/v4/zones/{zoneId}/purge_cache";

        using (var request = new HttpRequestMessage(new HttpMethod("POST"), url))
        {
            request.Headers.TryAddWithoutValidation("X-Auth-Email", authEmail);
            request.Headers.TryAddWithoutValidation("X-Auth-Key", authKey);

            var payload = new
            {
                files = cachedUrls
            };

            var json = JsonConvert.SerializeObject(payload);

            request.Content = new StringContent(json, Encoding.UTF8, "application/json");

            var response = await HttpClient.SendAsync(request);

            if (response.IsSuccessStatusCode)
            {
                log.LogInformation("Successfully cleared cache.");
                return new OkResult();
            }
            var error = await response.Content.ReadAsStringAsync();

            log.LogError(error);

            throw new Exception("Error clearing cache: " + error);
        }
    }
}