csharp-context.md

AWS Lambda context object in C#

When Lambda runs your function, it passes a context object to the handler. This object provides properties with information about the invocation, function, and execution environment.

Context properties

• FunctionName – The name of the Lambda function.
• FunctionVersion – The version of the function.
• InvokedFunctionArn – The Amazon Resource Name (ARN) that's used to invoke the function. Indicates if the invoker specified a version number or alias.
• MemoryLimitInMB – The amount of memory that's allocated for the function.
• AwsRequestId – The identifier of the invocation request.
• LogGroupName – The log group for the function.
• LogStreamName – The log stream for the function instance.
• RemainingTime (TimeSpan) – The number of milliseconds left before the execution times out.
• Identity – (mobile apps) Information about the Amazon Cognito identity that authorized the request.
• ClientContext – (mobile apps) Client context that's provided to Lambda by the client application.
• Logger The logger object for the function.

The following C# code snippet shows a simple handler function that prints some of the context information.

public async Task Handler(ILambdaContext context)
{
    Console.WriteLine("Function name: " + context.FunctionName);
    Console.WriteLine("RemainingTime: " + context.RemainingTime);
    await Task.Delay(TimeSpan.FromSeconds(0.42));
    Console.WriteLine("RemainingTime after sleep: " + context.RemainingTime);
}