in services/thumbnails/csharp/Startup.cs [40:117]
public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILogger<Startup> logger)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
logger.LogInformation("Service is starting...");
app.UseRouting();
var thumbBucket = GetEnvironmentVariable("BUCKET_THUMBNAILS");
var projectId = GetEnvironmentVariable("PROJECT_ID");
app.UseEndpoints(endpoints =>
{
endpoints.MapPost("/", async context =>
{
JToken pubSubMessage;
using (var reader = new StreamReader(context.Request.Body))
{
pubSubMessage = JValue.Parse(await reader.ReadToEndAsync());
logger.LogInformation("PubSub message: " + pubSubMessage);
}
var eventType = (string)pubSubMessage["message"]["attributes"]["eventType"];
var data = (string)pubSubMessage["message"]["data"];
var fileEvent = JValue.Parse(Encoding.UTF8.GetString(Convert.FromBase64String(data)));
if (eventType != "OBJECT_FINALIZE")
{
logger.LogInformation($"Event type {eventType} is not OBJECT_FINALIZE. Skipping file.");
return;
}
logger.LogInformation("Base 64 decoded file event: " + fileEvent);
var bucket = (string)fileEvent["bucket"];
var name = (string)fileEvent["name"];
using (var inputStream = new MemoryStream())
{
var client = await StorageClient.CreateAsync();
await client.DownloadObjectAsync(bucket, name, inputStream);
logger.LogInformation($"Downloaded '{name}' from bucket '{bucket}'");
using (var outputStream = new MemoryStream())
{
inputStream.Position = 0; // Reset to read
using (Image image = Image.Load(inputStream))
{
image.Mutate(x => x
.Resize(ThumbWidth, ThumbHeight)
);
logger.LogInformation($"Resized image '{name}' to {ThumbWidth}x{ThumbHeight}");
image.SaveAsPng(outputStream);
}
await client.UploadObjectAsync(thumbBucket, name, "image/png", outputStream);
logger.LogInformation($"Uploaded '{name}' to bucket '{thumbBucket}'");
var firestore = await FirestoreDb.CreateAsync(projectId);
var pictureStore = firestore.Collection("pictures");
var doc = pictureStore.Document(name);
var metadata = new Dictionary<string, object>()
{
{"thumbnail", true},
};
await doc.SetAsync(metadata, SetOptions.MergeAll);
logger.LogInformation($"Updated Firestore about thumbnail creation for {name}");
}
}
});
});
}