/// <summary>
/// Saves a new or updated alert.
/// </summary>
/// <param name="alert">The alert.</param>
/// <exception cref="ArgumentNullException">alert</exception>
/// <exception cref="ArgumentException">The alert must have an AlertId - alert</exception>
public void SaveAlert(JobAlert alert)
{
if (alert == null)
{
throw new ArgumentNullException(nameof(alert));
}
if (String.IsNullOrEmpty(alert.AlertId))
{
throw new ArgumentException("The alert must have an AlertId", nameof(alert));
}
var table = _tableClient.GetTableReference(_alertsTable);
table.CreateIfNotExistsAsync().Wait();
var query = _queryConverter.ToCollection(alert.Query);
query.Remove("page");
query.Remove("pagesize");
query.Remove("sort");
var serialised = query.ToString();
// Azure tables use an index clustered first by partition key then by row key,
// so use email as the partition key to make it easy to get all alerts for a user.
var entity = new JobAlertTableEntity()
{
PartitionKey = ToAzureKeyString(alert.Email),
RowKey = alert.AlertId,
Criteria = serialised,
Frequency = alert.Frequency,
JobsSet = alert.JobsSet.ToString()
};
try
{
table.Execute(TableOperation.InsertOrReplace(entity));
}
catch (StorageException ex)
{
if (ex.Message.Contains("(400) Bad Request"))
{
var alertQuery = _queryConverter.ToCollection(alert.Query).ToString();
LogHelper.Error <AzureTableStorageAlertsRepository>(alertQuery + " returned " + ex.RequestInformation.ExtendedErrorInformation.ErrorMessage, ex);
ex.ToExceptionless().Submit();
}
else
{
throw;
}
}
}
/// <summary>
/// Generates a new unique identifier based on the content of a job alert.
/// </summary>
/// <param name="alert">The alert.</param>
/// <returns></returns>
public string GenerateId(JobAlert alert)
{
if (alert == null)
{
throw new ArgumentNullException(nameof(alert));
}
if (String.IsNullOrEmpty(alert.Email))
{
throw new ArgumentException("The alert must include an email address to generate a unique ID", nameof(alert));
}
HashAlgorithm algorithm = SHA1.Create();
var bytes = Encoding.ASCII.GetBytes(alert.JobsSet + alert.Email + _queryConverter.ToCollection(alert.Query).ToString());
var hash = algorithm.ComputeHash(bytes);
StringBuilder sb = new StringBuilder();
for (int i = 0; i < hash.Length; i++)
{
sb.Append(hash[i].ToString("X2"));
}
return(sb.ToString().ToLowerInvariant());
}