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Failure simulation

Imposter can simulate failure types to enable you to test adverse scenarios, such as the connection being closed without receiving a response.

Injecting failures

Failures can be injected via configuration or using a script driven approach.

The failure takes effect after any request processing has completed (scripts, plugins etc.) but before the response is sent.

Note Failures can also be combined with performance simulation effects. For example to simulate a delay followed by a closed connection.

The supported failure types are:

Failure type Effect Configuration value
Empty response Send an empty HTTP response EmptyResponse
Close connection Close the connection before sending a response CloseConnection

Configuration driven

Specify the fail option in configuration:

# ...

  - method: GET
    path: /example1
      # send an empty HTTP response
      fail: EmptyResponse

  - method: GET
    path: /example2
      # close the connection before sending a response
      fail: CloseConnection

Script driven

If using Scripting, use the withFailure(...) method.

To send an empty response:


To close the connection:



You will see log entries similar to the following:

15:39:09 INFO  i.g.i.s.CharacteristicsService - 
  Simulating EmptyResponse failure for GET http://localhost:50204/example1