public async static Task Run(
[QueueTrigger("receiptitems", Connection = "AzureWebJobsStorage")] ReceiptQueueMessage receiptQueueItem,
[Table("receiptsTable", Connection = "AzureWebJobsStorage")] CloudTable receiptsTable,
[Queue("ocrqueue", Connection = "SmartServicesStorage")] ICollector <string> receiptOCRQueue,
[Blob("incontainer/receipts", System.IO.FileAccess.Read, Connection = "AzureWebJobsStorage")] string receiptBlob,
TraceWriter log)
{
log.Info($"Step is: {receiptQueueItem.ProcessingStep}");
switch (receiptQueueItem.ProcessingStep)
{
case 0: // processing
log.Info($"Step 0 for item: {receiptQueueItem}");
await CreateTableEntry(receiptQueueItem, receiptsTable);
StartOCR(receiptQueueItem, receiptOCRQueue);
break;
case 1: // complete
log.Info($"Processing Complete for item: {receiptQueueItem}");
UpdateTableStatus(receiptsTable, receiptQueueItem.Status, receiptQueueItem.ExpenseId);
break;
case 99: // retrying
log.Info($"Retrying Processing for item: {receiptQueueItem}");
UpdateTableStatus(receiptsTable, "Retrying", receiptQueueItem.ExpenseId);
StartOCR(receiptQueueItem, receiptOCRQueue);
break;
default:
break;
}
}
private static async Task CreateTableEntry(ReceiptQueueMessage receiptQueueItem, CloudTable receiptsTable)
{
// create table entry
var item = new ReceiptTableItem()
{
PartitionKey = "key",
RowKey = receiptQueueItem.ExpenseId,
ExpenseId = receiptQueueItem.ExpenseId,
UserId = receiptQueueItem.UserId,
Status = "Processing"
};
var operation = TableOperation.Insert(item);
await receiptsTable.ExecuteAsync(operation);
}
private static void StartOCR(ReceiptQueueMessage receiptQueueItem, ICollector <string> receiptOCRQueue)
{
// add message to OCR queue
var OCRCallbackKey = ConfigurationManager.AppSettings["OCRCallbackKey"];
var baseCallbackAddress = ConfigurationManager.AppSettings["BaseCallbackAddress"];
string imageUrl = string.Empty;
if (TryGetBlobLink(receiptQueueItem, out imageUrl))
{
var message = new OCRQueueMessage()
{
ItemId = receiptQueueItem.ExpenseId,
ItemType = "receipt",
ImageUrl = imageUrl,
Callback = $"{baseCallbackAddress}/ocrCallback?code={OCRCallbackKey}"
};
receiptOCRQueue.Add(JsonConvert.SerializeObject(message));
}
}
private static bool TryGetBlobLink(ReceiptQueueMessage receiptQueueItem, out string imageUrl)
{
var storageAccount = CloudStorageAccount.Parse(ConfigurationManager.AppSettings["AzureWebJobsStorage"]);
var blobClient = storageAccount.CreateCloudBlobClient();
var blobContainer = blobClient.GetContainerReference("receipts");
imageUrl = string.Empty;
if (blobContainer.Exists())
{
var blob = blobContainer.GetBlockBlobReference(receiptQueueItem.ExpenseId);
SharedAccessBlobPolicy sasConstraints = new SharedAccessBlobPolicy();
sasConstraints.SharedAccessStartTime = DateTime.UtcNow.AddMinutes(-5);
sasConstraints.SharedAccessExpiryTime = DateTime.UtcNow.AddHours(24);
sasConstraints.Permissions = SharedAccessBlobPermissions.Read;
string sasBlobToken = blob.GetSharedAccessSignature(sasConstraints);
imageUrl = blob.Uri + sasBlobToken;
}
return(!string.IsNullOrEmpty(imageUrl));
}
