public async Task <NumberPlateTrigger> FunctionHandler(S3Event evnt, ILambdaContext context)
{
var s3Event = evnt.Records?[0].S3;
context.Logger.LogLine("EVENT Received: " + JsonConvert.SerializeObject(s3Event));
if (regExNumberPlate == null)
{
context.Logger.LogLine("regExNumberPlate is not yet populated. Calling getNumberPlateFromSecretsManager()...");
regExNumberPlate = await getNumberPlateFromSecretsManager(context);
context.Logger.LogLine("regExNumberPlate is " + regExNumberPlate);
}
NumberPlateTrigger result = new NumberPlateTrigger
{
bucket = s3Event.Bucket.Name,
key = s3Event.Object.Key,
contentType = "",
contentLength = s3Event.Object.Size,
charge = int.Parse(Environment.GetEnvironmentVariable("TollgateCharge")),
numberPlate = new NumberPlate()
{
numberPlateRegEx = this.regExNumberPlate,
detected = false
}
};
AWSXRayRecorder recorder = AWSXRayRecorder.Instance;
recorder.BeginSubsegment("TollGantry::Detect Number Plate in Captured Image");
recorder.AddMetadata("bucket", s3Event.Bucket.Name);
recorder.AddMetadata("key", s3Event.Object.Key);
recorder.AddMetadata("regex", this.regExNumberPlate);
//
// TODO: Call Rekognition to detect text in the captured image
//
recorder.EndSubsegment();
//
// Kick off the step function
//
context.Logger.LogLine("Starting the state machine");
IAmazonStepFunctions stepFunctionsClient = new AmazonStepFunctionsClient();
await stepFunctionsClient.StartExecutionAsync(new StartExecutionRequest()
{
StateMachineArn = Environment.GetEnvironmentVariable("NumberPlateProcessStateMachine"), Input = JsonConvert.SerializeObject(result)
});
context.Logger.LogLine("State machine started");
return(result);
}
public async Task <NumberPlateTrigger> FunctionHandler(S3Event evnt, ILambdaContext context)
{
var s3Event = evnt.Records?[0].S3;
context.Logger.LogLine("EVENT Received: " + JsonConvert.SerializeObject(s3Event));
if (regExNumberPlate == null)
{
context.Logger.LogLine("regExNumberPlate is not yet populated. Calling getNumberPlateFromSecretsManager()...");
regExNumberPlate = await getNumberPlateFromSecretsManager(context);
context.Logger.LogLine("regExNumberPlate is " + regExNumberPlate);
}
//var response = await this.S3Client.GetObjectMetadataAsync(s3Event.Bucket.Name, s3Event.Object.Key);
//return response.Headers.ContentType;
NumberPlateTrigger result = new NumberPlateTrigger
{
bucket = s3Event.Bucket.Name,
key = s3Event.Object.Key,
contentType = "",
contentLength = s3Event.Object.Size,
charge = int.Parse(Environment.GetEnvironmentVariable("TollgateCharge")),
numberPlate = new NumberPlate()
{
numberPlateRegEx = this.regExNumberPlate,
detected = false
}
};
recorder.BeginSubsegment("TollGantry::Detect Number Plate in Captured Image");
recorder.AddMetadata("bucket", s3Event.Bucket.Name);
recorder.AddMetadata("key", s3Event.Object.Key);
recorder.AddMetadata("regex", this.regExNumberPlate);
S3Object s3Object = new S3Object();
s3Object.Bucket = s3Event.Bucket.Name;
s3Object.Name = s3Event.Object.Key;
DetectTextRequest detectTextReq = new DetectTextRequest {
Image = new Image {
S3Object = s3Object
}
};
context.Logger.LogLine("Calling Rekognition ... ");
DetectTextResponse detectTextResponse = await rekognitionClient.DetectTextAsync(detectTextReq);
context.Logger.LogLine($"Response from Rekognition: {JsonConvert.SerializeObject(detectTextResponse)}");
// Check if the a valid number was detected...
foreach (var textItem in detectTextResponse.TextDetections)
{
if (!result.numberPlate.detected && textItem.Type.Value == "LINE" && textItem.Confidence > float.Parse(Environment.GetEnvironmentVariable("RekognitionTextMinConfidence")))
{
Regex regex = new Regex(regExNumberPlate);
MatchCollection matches = regex.Matches(textItem.DetectedText);
context.Logger.LogLine($"Matches collection: {matches.Count}");
string plateNumber = "";
foreach (Match match in matches)
{
plateNumber += (match.Groups[1].Value + match.Groups[2].Value);
}
if (!string.IsNullOrEmpty(plateNumber))
{
result.numberPlate.detected = true;
result.numberPlate.confidence = textItem.Confidence;
result.numberPlate.numberPlateString = plateNumber;
context.Logger.LogLine($"A valid plate number was detected ({result.numberPlate.numberPlateString})");
}
}
}
recorder.EndSubsegment();
//
// At this point, we either know it is a valid number plate
// or it couldn't be determined with adequate confidence
// so we need manual intervention
//
//
// Kick off the step function
//
context.Logger.LogLine("Starting the state machine");
//TODO: add code to start the state machine
context.Logger.LogLine("State machine started");
return(result);
}