public static async Task RunAsync([QueueTrigger("mailservice", Connection = "AzureWebJobsStorage")]
QueueMail myQueueItem, TraceWriter log, ExecutionContext context)
{
SmtpServer smtpServer;
var toDomain = myQueueItem.To.Split('@').Last();
if (Filters.Contains(toDomain))
{
var lua = $@"
local function GetServer(keys)
for _,key in ipairs(keys) do
local count = redis.call('GET', key)
if(count ~= 1) then
local current = redis.call('INCR', key)
if(current == 1) then
redis.call('EXPIRE', key, {LockSeconds})
return key
end
end
end
return nil
end
return GetServer(KEYS)";
var redisKeys = Enumerable.Range(0, SmtpServers.Count).Select(p => (RedisKey)$"{p}:{toDomain}")
.ToArray();
var result = Redis.Value.GetDatabase(RedisDbNumber).ScriptEvaluate(lua, redisKeys);
if (result.IsNull)
{
throw new ConstraintException();
}
var index = int.Parse(result.ToString().Split(':').First());
smtpServer = SmtpServers[index];
}
else
{
smtpServer = SmtpServers[0];
}
var smtpClient = new SmtpClient(smtpServer.Host, smtpServer.Port)
{
Credentials = new NetworkCredential(smtpServer.UserName, smtpServer.Password)
};
var mail = new MailMessage(myQueueItem.From, string.Join(",", myQueueItem.To))
{
Subject = myQueueItem.Subject,
Body = myQueueItem.Body,
BodyEncoding = Encoding.UTF8,
IsBodyHtml = true
};
if (myQueueItem.AttachedBlobNames.Any())
{
if (!await BlobContainer.Value.ExistsAsync())
{
throw new Exception($"No blob");
}
var tasks = myQueueItem.AttachedBlobNames.AsParallel().Select(blobname => Task.Run(async() =>
{
var block = BlobContainer.Value.GetBlockBlobReference(blobname);
if (!await block.ExistsAsync())
{
throw new Exception($"No block");
}
var stream = await block.OpenReadAsync();
var fileName = blobname.Split('/').Last();
return(new Attachment(stream, fileName));
})).ToArray();
var attachments = await Task.WhenAll(tasks);
foreach (var attachment in attachments)
{
mail.Attachments.Add(attachment);
}
}
smtpClient.SendCompleted += (sender, e) =>
{
smtpClient.Dispose();
mail.Dispose();
if (e.Cancelled)
{
throw new SmtpException($"Cancelled by smtp server.");
}
if (e.Error != null)
{
throw e.Error;
}
if (!(e.UserState is string[] blobnames))
{
return;
}
if (blobnames.Any())
{
blobnames.AsParallel().ForAll(async blobname =>
await BlobContainer.Value.GetBlockBlobReference(blobname).DeleteAsync());
}
};
smtpClient.SendAsync(mail, myQueueItem.AttachedBlobNames);
}
public static async Task <IActionResult> Run([HttpTrigger(AuthorizationLevel.Anonymous, "post", Route = null)]
HttpRequest req, TraceWriter log)
{
if (!req.Form.TryGetValue("From", out var from))
{
return(new BadRequestErrorMessageResult($"Key:From is missing."));
}
if (!req.Form.TryGetValue("To", out var to))
{
return(new BadRequestErrorMessageResult($"Key:To is missing."));
}
if (!req.Form.TryGetValue("Subject", out var subject))
{
return(new BadRequestErrorMessageResult($"Key:Subject is missing."));
}
if (!req.Form.TryGetValue("Body", out var body))
{
return(new BadRequestErrorMessageResult($"Key:Body is missing."));
}
var blobNames = new ConcurrentBag <string>();
if (req.Form.Files.Count > 0)
{
if (await BlobContainer.Value.CreateIfNotExistsAsync())
{
await BlobContainer.Value.SetPermissionsAsync(new BlobContainerPermissions
{
PublicAccess = BlobContainerPublicAccessType.Container
});
}
foreach (var file in req.Form.Files)
{
var fileName = file.FileName;
string blobName;
CloudBlockBlob block;
do
{
blobName = $"{Guid.NewGuid()}/{fileName}";
block = BlobContainer.Value.GetBlockBlobReference(blobName);
} while (await block.ExistsAsync());
blobNames.Add(blobName);
var stream = file.OpenReadStream();
await block.UploadFromStreamAsync(stream);
}
}
var queueMail = new QueueMail
{
From = from[0],
To = to[0],
Subject = subject[0],
Body = body[0],
AttachedBlobNames = blobNames.ToArray()
};
await Queue.Value.CreateIfNotExistsAsync();
var json = JsonConvert.SerializeObject(queueMail);
var message = new CloudQueueMessage(json);
await Queue.Value.AddMessageAsync(message);
return(new OkObjectResult($"Enqueue mail success."));
}
