"truncateActual" results in null pointer exceptions

[papiomytoglou]

Proposal

Using a JSON mapping file which includes truncateActual in standalone results in null pointer exceptions for all requests with non-matching URIs or date/time values.

For example, when including the matcher below in a mapping

"queryParameters": {
  "datetime": {
    "equalToDateTime": "now",
    "truncateExpected": "first hour of day",
    "truncateActual": "first hour of day"
  }
}

all requests with matching URIs or datetime values will still be handled correctly but all other requests will result in the following null pointer exception:

java.lang.NullPointerException: Cannot invoke "java.time.ZonedDateTime.truncatedTo(java.time.temporal.TemporalUnit)" because "input" is null

Removing truncateActual stops the exception from being thrown but is not a solution since the two matchers are not equivalent.

Tested in standalone versions 3.0.1, 3.1.0 and 3.2.0

Reproduction steps

Create a JSON file in mappings with the following data:

{
  "request": {
    "method": "GET",
    "urlPath": "/first",
    "queryParameters": {
      "datetime": {
        "equalToDateTime": "now",
        "truncateExpected": "first hour of day",
        "truncateActual": "first hour of day"
      }
    }
  },
  "response": {
    "status": 200,
    "body": "First stub"
  }
}

Create a second JSON file, also in mappings, with the following data:

{
  "request": {
    "method": "GET",
    "urlPath": "/second"
  },
  "response": {
    "status": 200,
    "body": "Second stub"
  }
}

Start wiremock-standalone-3.2.0.jar locally on port 80 only using the above two mappings then open a browser and navigate to the following URIs replacing 2023-10-27 with the current date:

http://localhost/first?datetime=2023-10-27T17:09:10.739Z
# Matches successfully

http://localhost/second
# Matches successfully

http://localhost/first
# Matching URI, absent date/time parameter, returns null pointer exception

http://localhost/third
http://localhost/nonexistent
http://localhost/12345
http://localhost/employee?id=42
# Non-matching URIs, all return null pointer exceptions

http://localhost/first?datetime=2047-01-01T17:09:10.739Z
# Matching URI, non-matching date/time parameter value, returns "Request was not matched" response

http://localhost/nonexistent?datetime=2023-10-27T17:09:10.739Z
# Non-matching URI, matching date/time parameter value, returns "Request was not matched" response

References

No response

[papiomytoglou]

It looks like the order the mappings are added with matters. If the mapping containing truncateActual is added last then even the requests with matching URIs return a null pointer exception. So what I described initially is probably the best case scenario.