internal static async Task ReplicateBlobAsync(PhotoModel model, TextWriter log)
{
//The source connection string needs to be in AppSettings using the
//storage account name.
var sourceConnectionString = ConfigurationManager.AppSettings[model.StorageAccountName];
//The target connection string is the local region's storage account
var targetConnectionString = SettingsHelper.LocalStorageConnectionString;
//Copy from the upload container to the photos container,
// potentially across storage accounts
await log.WriteLineAsync("sourceConnectionString: " + sourceConnectionString);
await log.WriteLineAsync("targetConnectionString: " + targetConnectionString);
var storageRepo = new StorageRepository(sourceConnectionString);
var container = await storageRepo.ReplicateBlobAsync(
targetConnectionString,
StorageConfig.UserUploadBlobContainerName,
StorageConfig.PhotosBlobContainerName,
model.ServerFileName, log);
//Monitor the copy operation and wait for it to finish
//before proceeding
await storageRepo.MonitorCopy(container, model.ServerFileName, log);
}
internal static async Task SaveToRedisAsync(PhotoModel p, TextWriter log)
{
//Use repository to add to all caches
IDatabase cache = RedisCache.Connection.GetDatabase();
RedisRepository repo = new RedisRepository(cache);
await repo.AddPhotoToCachesAsync(p);
}
internal static async Task SaveToTableStorageAsync(PhotoModel p, TextWriter log)
{
var storageConnectionString = SettingsHelper.LocalStorageConnectionString;
var repo = new StorageRepository(storageConnectionString);
var result = await repo.SaveToTableStorageAsync(DAL.Azure.StorageConfig.TableName, p);
await log.WriteLineAsync("Save to table HTTP result: " + result);
}
// This function will get triggered/executed when a new message is written
// on an Azure Queue called queue.
public static async Task ProcessQueueMessage(
[QueueTrigger("uploadqueue")] string message,
TextWriter log)
{
log.WriteLineAsync(message).Wait();
var m = message.Split(',');
await log.WriteAsync("Message received: " + m);
var model = new PhotoModel
{
ID = m[0],
ServerFileName = m[1],
StorageAccountName = m[2],
Owner = m[3],
OwnerName = m[4],
BlobURL = m[5],
OriginRegion = m[6]
};
//Copy blob from source to destination
await log.WriteAsync("Replicating blob...");
await Helpers.ReplicateBlobAsync(model, log);
try
{
//Change the blob URL to point to the new location!
await log.WriteAsync("Getting blob URIs");
string storageConnectionString = SettingsHelper.LocalStorageConnectionString;
var repo = new StorageRepository(storageConnectionString);
model.BlobURL = repo.GetBlobURI(model.ServerFileName, StorageConfig.PhotosBlobContainerName).ToString();
model.ThumbnailURL = repo.GetBlobURI(model.ServerFileName, StorageConfig.ThumbnailsBlobContainerName).ToString();
//Create thumbnail
await log.WriteAsync("Creating thumbnail");
await Helpers.CreateThumbnailAsync(repo, model.ServerFileName, log);
//Store in table storage
await log.WriteAsync("Saving to table storage");
await Helpers.SaveToTableStorageAsync(model, log);
//Add to Redis cache
await log.WriteAsync("Saving to Redis");
await Helpers.SaveToRedisAsync(model, log);
}
catch (Exception oops)
{
await log.WriteLineAsync(oops.Message);
}
}
/// <summary>
/// Saves an entity to Azure table storage
/// </summary>
/// <param name="tableName">The name of the table to save to</param>
/// <param name="model">The PhotoModel object to be saved</param>
/// <returns>System.String - the HTTP status code of the save operation</returns>
public async Task<string> SaveToTableStorageAsync(
string tableName,
PhotoModel model)
{
//We use the DateAdded field for cross-partition queries
DateTime now = System.DateTime.Now;
model.DateAdded = now;
PhotoEntity entity = new PhotoEntity(model);
//These properties are used in a full table scan to populate
//all photos for all users. Needed as some way to get the
//items for a single day for all users.
entity.DayAdded = now.Day;
entity.MonthAdded = now.Month;
entity.YearAdded = now.Year;
var client = _account.CreateCloudTableClient();
var table = client.GetTableReference(tableName);
var operation = TableOperation.InsertOrReplace(entity);
var result = await table.ExecuteAsync(operation);
//TODO: Do we need to check the HTTP status code here?
return result.HttpStatusCode.ToString();
}