How to download image using rest template?

Question

I have the following code:

restTemplate.getForObject("http://img.championat.com/news/big/l/c/ujejn-runi_1439911080563855663.jpg", File.class);

I especially took image which doesn't require authorization and available absolutely for all.

when following code executes I see the following stacktrace:

org.springframework.web.client.RestClientException: Could not extract response: no suitable HttpMessageConverter found for response type [class java.io.File] and content type [image/jpeg]
    at org.springframework.web.client.HttpMessageConverterExtractor.extractData(HttpMessageConverterExtractor.java:108)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:559)
    at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:512)
    at org.springframework.web.client.RestTemplate.getForObject(RestTemplate.java:243)
    at com.terminal.controller.CreateCompanyController.handleFileUpload(CreateCompanyController.java:615)

what do I wrong?

Answer 1

Image is a byte array, so you need to use byte[].class object as a second argument for RestTemplate.getForObject:

String url = "http://img.championat.com/news/big/l/c/ujejn-runi_1439911080563855663.jpg";
byte[] imageBytes = restTemplate.getForObject(url, byte[].class);
Files.write(Paths.get("image.jpg"), imageBytes);

To make it work, you will need to configure a ByteArrayHttpMessageConverter in your application config:

@Bean
public RestTemplate restTemplate(List<HttpMessageConverter<?>> messageConverters) {
    return new RestTemplate(messageConverters);
}

@Bean
public ByteArrayHttpMessageConverter byteArrayHttpMessageConverter() {
    return new ByteArrayHttpMessageConverter();
}

I've tested this in a Spring Boot project and the image is saved to a file as expected.