MissingRequiredPropertyException in a response

The Java API Client distinguishes optional and required properties. Optional properties are marked with the @Nullable annotation.

When an API object is built and a required property hasn’t been set, a MissingRequiredPropertyException is thrown. This applies both to request object built by your application and to response objects returned by Elasticsearch, so that you can be assured that a property that does not have the @Nullable annotation will never be null.

However, there may be bugs in the Elasticsearch API specification where a response object’s property is incorrectly required, leading to a MissingRequiredPropertyException when deserializing a response. If this happens, here’s how you can work around it:

    ApiTypeHelper.DANGEROUS_disableRequiredPropertiesCheck(true);
    SomeRequest request = SomeRequest.of(...);
    SomeResponse response = esClient.someApi(request);
    ApiTypeHelper.DANGEROUS_disableRequiredPropertiesCheck(false);
    // Do something with response
}

The DANGEROUS_disableRequiredPropertiesCheck method disables required property checks on the current thread, and for response deserialization in asynchronous requests. As its name implies, it is dangerous as it removes the guarantees of properties that are not @Nullable. This is a temporary workaround until the issue is fixed.

Note that the result of this method is an AutoCloseable object that resets required property checks to its previous setting. You can therefore use it in a try-with-resource block as follows:

try (ApiTypeHelper.DisabledChecksHandle h =
        ApiTypeHelper.DANGEROUS_disableRequiredPropertiesCheck(true)) {
    SomeRequest request = SomeRequest.of(...);
    SomeResponse response = esClient.someApi(request);
    // Do something with response
}