public static async Task Run(
[EventGridTrigger] EventGridEvent eventGridEvent,
[Blob("{data.url}", FileAccess.Read)] Stream input,
ILogger log)
{
try {
if (input != null)
{
var createdEvent = ((JObject)eventGridEvent.Data).ToObject <StorageBlobCreatedEventData>();
var extension = Path.GetExtension(createdEvent.Url);
var encoder = GetEncoder(extension);
if (encoder != null)
{
var thumbnailWidth = Convert.ToInt32(Environment.GetEnvironmentVariable("THUMBNAIL_WIDTH"));
var thumbContainerName = Environment.GetEnvironmentVariable("THUMBNAIL_CONTAINER_NAME");
var checkedImageContainerName = Environment.GetEnvironmentVariable("CHECKED_IMAGES_CONTAINER_NAME");
var storageAccount = CloudStorageAccount.Parse(BLOB_STORAGE_CONNECTION_STRING);
var blobClient = storageAccount.CreateCloudBlobClient();
var container = blobClient.GetContainerReference(thumbContainerName);
var blobName = GetBlobNameFromUrl(createdEvent.Url);
var blockBlob = container.GetBlockBlobReference(blobName);
bool isContentApproved = false;
List <EvaluationData> evaluationData = new List <EvaluationData>();
// check image by sending to MS Cognitive services content moderator AI
// first, create new ContentModerator
using (var client = NewClient()) {
EvaluationData imageData = EvaluateImage(client, createdEvent.Url);
if (imageData.ImageModeration.IsImageAdultClassified.HasValue && imageData.ImageModeration.IsImageRacyClassified.HasValue)
{
if (!imageData.ImageModeration.IsImageAdultClassified.Value && !imageData.ImageModeration.IsImageRacyClassified.Value)
{
using (var output = new MemoryStream())
using (Image <Rgba32> image = SixLabors.ImageSharp.Image.Load(input)) {
var divisor = image.Width / thumbnailWidth;
var height = Convert.ToInt32(Math.Round((decimal)(image.Height / divisor)));
image.Mutate(x => x.Resize(thumbnailWidth, height));
image.Save(output, encoder);
output.Position = 0;
await blockBlob.UploadFromStreamAsync(output);
}
}
}
};
}
else
{
log.LogInformation($"No encoder support for: {createdEvent.Url}");
}
}
}
catch (Exception ex) {
log.LogInformation(ex.Message);
throw;
}
}
/// <summary>
/// Send an image url to cognitive services to be checked.
/// </summary>
/// <param name="client"></param>
/// <param name="imageUrl"></param>
/// <returns></returns>
private static EvaluationData EvaluateImage(ContentModeratorClient client, string imageUrl)
{
var url = new BodyModel("URL", imageUrl.Trim());
var imageData = new EvaluationData();
imageData.ImageUrl = url.Value;
// Evaluate for adult and racy content.
imageData.ImageModeration = client.ImageModeration.EvaluateUrlInput("application/json", url, true);
Thread.Sleep(1000);
return(imageData);
}
