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javajacksonspring-webclient

Webclient + Jackson: how to setup deserialization to convert snake_case into camelCase?

I'd like to avoid having to prefix my attributes with @JsonProperty("property_name") and instead just setup the Spring WebClient builder to convert all snake_cases into camelCases.

Is that possible?

Solution

  • Read 9.4.3. Customize the Jackson ObjectMapper and 10.A.4. JSON properties to be aware how many options we can define from configuration file. In your case you need to set:

    spring.jackson.property-naming-strategy=SNAKE_CASE

    If you want to change configuration only for deserialisation you need to customise a way how WebClient is created.

    import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.PropertyNamingStrategy;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.codec.json.Jackson2JsonDecoder;
import org.springframework.web.reactive.function.client.ExchangeStrategies;
import org.springframework.web.reactive.function.client.WebClient;

@Configuration
public class WebClientConfiguration {

    @Bean
    public WebClient webClient(ObjectMapper baseConfig) {
        ObjectMapper newMapper = baseConfig.copy();
        newMapper.setPropertyNamingStrategy(PropertyNamingStrategy.SNAKE_CASE);

        ExchangeStrategies exchangeStrategies = ExchangeStrategies.builder()
                .codecs(configurer ->
                        configurer.defaultCodecs().jackson2JsonDecoder(new Jackson2JsonDecoder(newMapper)))
                .build();
        return WebClient.builder()
                .baseUrl("http://localhost:8080")
                .exchangeStrategies(exchangeStrategies)
                .build();
    }
}

    See: