.NET Core function error handling

If the handler reports a .NET Core function execution or loading error, the runtime automatically catches the error and returns a JSON document with information about the error type. For more information about the JSON document format, see Invoking a function.

The error info is also written to the execution log. You can view the log via the Yandex Cloud CLI or the management console.

Examples of error handlingExamples of error handling

Case 1: User code goes outside the array boundaries, causing the function to throw IndexOutOfRangeException. The runtime catches the exception and generates a JSON document containing the error message (the errorMessage field), error type (the errorType field), and stack trace (the stackTrace field).

Function code:

public class Handler {
  public int FunctionHandler(byte[] input) {
    readonly var array = new int[]{1, 2, 3, 4, 5};
    // At this point, the function throws IndexOutOfRangeException.
    return array[15];
  }
}

JSON document returned:

{
  "errorMessage": "Index was outside the bounds of the array",
  "errorType": "System.IndexOutOfRangeException",
  "stackTrace": [
    ...
  ]
}

Case 2: User code indicates an error by throwing an exception from the function.

Function code:

public class Handler {
  public int FunctionHandler(byte[] input) {
    throw new SystemException("Some error message");
  }
}

JSON document returned:

{
  "errorMessage": "Some error message",
  "errorType": "System.SystemException",
  "stackTrace": [
    ...
  ]
}