string TryGetFromCache(string query, Func <string> retrieveRemoteContent)
{
var contentByteArray = System.Text.Encoding.Unicode.GetBytes(query);
using (var sha256 = System.Security.Cryptography.SHA256.Create())
{
var cacheKey = sha256.ComputeHash(contentByteArray);
var cacheKeyBase64 = new string(cacheKey.Select(@byte => @byte.ToString("X")[0]).ToArray());
if (File.Exists(cacheKeyBase64))
{
return(File.ReadAllText(cacheKeyBase64));
}
var metrics = new MetricsCollector();
var newContent = metrics.LogAndInvoke(() => retrieveRemoteContent(), "retrieveRemoteContent");
var contentWithMeta = $"{{\"query\":{query},\"retrieveDuration\":{(metrics as IEnumerable<Metrics>).Single().Duration.TotalMilliseconds},"
+ newContent.Substring(1);
File.WriteAllText(cacheKeyBase64, contentWithMeta);
return(newContent);
}
}
