[ExcludeFromCodeCoverage] //Mostly using the ImageSharp SDK so not worth testing.
public IActionResult Run([HttpTrigger(AuthorizationLevel.Function, "post", Route = null)] HttpRequest req, ILogger log)
{
// Configure logging
ScopedData data = new ScopedData();
if (data.InitialiseFromRequestHeaders(req))
{
data.Apply();
}
try
{
log.LogInformation("{functionName}: Image resize starting", FunctionName);
using Image image = Image.Load(req.Body);
// Note we don't dispose this stream on purpose as it's used by the http server plumbing to serve the reponse.
MemoryStream output = new MemoryStream();
// Resize things down to a max width of x to ensure they're small enough for cog services
if (image.Width > ResizeToWidthPixels)
{
// If you pass 0 as any of the values for width and height dimensions then ImageSharp will automatically determine the correct opposite dimensions size to preserve the original aspect ratio.
// https://docs.sixlabors.com/articles/imagesharp/resize.html
image.Mutate(x => x.Resize(ResizeToWidthPixels, 0));
}
image.Save(output, new JpegEncoder());
output.Position = 0;
log.LogInformation("{functionName}: Image resize complete sending result", FunctionName);
return(new FileStreamResult(output, ReturnedContentType));
}
catch (Exception ex)
{
log.LogError(ex, "{functionName}: Failed to resize image", FunctionName);
ObjectResult internalErrorResponse = new ObjectResult($"Failed while attempting to resize image: {ex.Message}")
{
// Ensure a 500 response code as likely to be retryable error
StatusCode = 500
};
return(internalErrorResponse);
}
finally
{
log.LogInformation("{functionName}: Completed", FunctionName);
}
}
/// <summary>
/// Extension method to initialise the ScopedData instance from an incoming http Request.
/// </summary>
/// <param name="data">Reference to ScopedData instance.</param>
/// <param name="req">The incoming http request.</param>
/// <returns>boolean indicating whether any of the values have been set.</returns>
public static bool InitialiseFromRequestHeaders(this ScopedData data, HttpRequest req)
{
bool updated = false;
// If we have a correlation id in the header use it. This is preferred as we can still
// log the creation of the BlobInfo object.
if (req.Headers.ContainsKey(GeneralConstants.CorrelationIdHeaderName))
{
StringValues correlationId = req.Headers[GeneralConstants.CorrelationIdHeaderName];
// We don't currently support a non-guid correlation id
if (!Guid.TryParse(correlationId, out Guid corrId))
{
throw new NotSupportedException($"The {GeneralConstants.CorrelationIdHeaderName} header is not a valid Guid");
}
data.AddCustomData(GeneralConstants.CorrelationIdKey, corrId.ToString());
updated = true;
}
return(updated);
}
[ExcludeFromCodeCoverage] //This function just calls other services which are tested so there is no logic here that can be tested.
public async Task RunAsync([EventGridTrigger] EventGridEvent eventGridEvent, ILogger log)
{
try
{
// Get data from event grid event
dynamic eventGridEventData = JsonConvert.DeserializeObject(eventGridEvent.Data.ToString());
Uri uri = new Uri(eventGridEventData.url.ToString());
// Generate correlation id and set Telemetry
Guid correlation = _blobInfoFactoryService.CreateCorrelationId();
ScopedData scopedData = new ScopedData();
scopedData.AddCustomData(GeneralConstants.CorrelationIdKey, correlation.ToString()).Apply();
log.LogInformation("Started: {functionName} {uri}, {name}", _functionName, uri, uri.Segments.Last());
// Exclude empty files and folders
if (!string.IsNullOrEmpty(uri.AbsoluteUri))
{
// Generate BlobInfo
BlobInfo blobInfo = _blobInfoFactoryService.CreateBlobInfo(uri, uri.Segments.Last(), correlation);
log.LogInformation("{functionName}: created BlobInfo", _functionName);
// Send service bus message
await _serviceBusService.SubmitBlobInfoToServiceBus(blobInfo);
log.LogInformation("{functionName}: submitted BlobInfo to Service Bus", _functionName);
}
}
catch (Exception ex)
{
log.LogError(ex, "{functionName}: Failed to submit BlobInfo to Service Bus for {eventData}", _functionName, eventGridEvent.Data.ToString());
throw;
}
finally
{
log.LogInformation("{functionName}: Completed {eventData}", _functionName, eventGridEvent.Data.ToString());
}
}
