JarCastingForm Encoder
This module adds support for encoding application/x-www-form-urlencoded and multipart/form-data forms.
Add dependency
Include the dependency to your app:
Maven:
<dependencies>
...
<dependency>
<groupId>io.github.openfeign.form</groupId>
<artifactId>feign-form</artifactId>
<version>3.8.0</version>
</dependency>
...
</dependencies>
Gradle:
compile 'io.github.openfeign.form:feign-form:3.8.0'
Requirements
The feign-form extension depend on OpenFeign and its concrete versions:
- all
feign-formreleases before 3.5.0 works withOpenFeign9.* versions; - starting from
feign-form's version 3.5.0, the module works withOpenFeign10.1.0 versions and greater.
IMPORTANT: there is no backward compatibility and no any gurantee that the
feign-form's versions after 3.5.0 work withOpenFeignbefore 10.*.OpenFeignwas refactored in 10th release, so the best approach - use the freshestOpenFeignandfeign-formversions.
Notes:
-
spring-cloud-openfeign uses
OpenFeign9.* till v2.0.3.RELEASE and uses 10.* after. Anyway, the dependency already has suitablefeign-formversion, see dependency pom, so you don't need to specify it separately; -
spring-cloud-starter-feignis a deprecated dependency and it always uses theOpenFeign's 9.* versions.
Usage
Add FormEncoder to your Feign.Builder like so:
SomeApi github = Feign.builder()
.encoder(new FormEncoder())
.target(SomeApi.class, "http://api.some.org");
Moreover, you can decorate the existing encoder, for example JsonEncoder like this:
SomeApi github = Feign.builder()
.encoder(new FormEncoder(new JacksonEncoder()))
.target(SomeApi.class, "http://api.some.org");
And use them together:
interface SomeApi {
@RequestLine("POST /json")
@Headers("Content-Type: application/json")
void json (Dto dto);
@RequestLine("POST /form")
@Headers("Content-Type: application/x-www-form-urlencoded")
void from (@Param("field1") String field1, @Param("field2") String[] values);
}
You can specify two types of encoding forms by Content-Type header.
application/x-www-form-urlencoded
interface SomeApi {
@RequestLine("POST /authorization")
@Headers("Content-Type: application/x-www-form-urlencoded")
void authorization (@Param("email") String email, @Param("password") String password);
// Group all parameters within a POJO
@RequestLine("POST /user")
@Headers("Content-Type: application/x-www-form-urlencoded")
void addUser (User user);
class User {
Integer id;
String name;
}
}
multipart/form-data
interface SomeApi {
// File parameter
@RequestLine("POST /send_photo")
@Headers("Content-Type: multipart/form-data")
void sendPhoto (@Param("is_public") Boolean isPublic, @Param("photo") File photo);
// byte[] parameter
@RequestLine("POST /send_photo")
@Headers("Content-Type: multipart/form-data")
void sendPhoto (@Param("is_public") Boolean isPublic, @Param("photo") byte[] photo);
// FormData parameter
@RequestLine("POST /send_photo")
@Headers("Content-Type: multipart/form-data")
void sendPhoto (@Param("is_public") Boolean isPublic, @Param("photo") FormData photo);
// Group all parameters within a POJO
@RequestLine("POST /send_photo")
@Headers("Content-Type: multipart/form-data")
void sendPhoto (MyPojo pojo);
class MyPojo {
@FormProperty("is_public")
Boolean isPublic;
File photo;
}
}
In the example above, the sendPhoto method uses the photo parameter using three different supported types.
Filewill use the File's extension to detect theContent-Type;byte[]will useapplication/octet-streamasContent-Type;FormDatawill use theFormData'sContent-TypeandfileName;- Client's custom POJO for grouping parameters (including types above).
FormData is custom object that wraps a byte[] and defines a Content-Type and fileName like this:
FormData formData = new FormData("image/png", "filename.png", myDataAsByteArray);
someApi.sendPhoto(true, formData);
Spring MultipartFile and Spring Cloud Netflix @FeignClient support
You can also use Form Encoder with Spring MultipartFile and @FeignClient.
Include the dependencies to your project's pom.xml file:
<dependencies>
<dependency>
<groupId>io.github.openfeign.form</groupId>
<artifactId>feign-form</artifactId>
<version>3.8.0</version>
</dependency>
<dependency>
<groupId>io.github.openfeign.form</groupId>
<artifactId>feign-form-spring</artifactId>
<version>3.8.0</version>
</dependency>
</dependencies>
@FeignClient(
name = "file-upload-service",
configuration = FileUploadServiceClient.MultipartSupportConfig.class
)
public interface FileUploadServiceClient extends IFileUploadServiceClient {
public class MultipartSupportConfig {
@Autowired
private ObjectFactory<HttpMessageConverters> messageConverters;
@Bean
public Encoder feignFormEncoder () {
return new SpringFormEncoder(new SpringEncoder(messageConverters));
}
}
}
Or, if you don't need Spring's standard encoder:
@FeignClient(
name = "file-upload-service",
configuration = FileUploadServiceClient.MultipartSupportConfig.class
)
public interface FileUploadServiceClient extends IFileUploadServiceClient {
public class MultipartSupportConfig {
@Bean
public Encoder feignFormEncoder () {
return new SpringFormEncoder();
}
}
}
Thanks to tf-haotri-pham for his feature, which makes use of Apache commons-fileupload library, which handles the parsing of the multipart response. The body data parts are held as byte arrays in memory.
To use this feature, include SpringManyMultipartFilesReader in the list of message converters for the Decoder and have the Feign client return an array of MultipartFile:
@FeignClient(
name = "${feign.name}",
url = "${feign.url}"
configuration = DownloadClient.ClientConfiguration.class
)
public interface DownloadClient {
@RequestMapping("/multipart/download/{fileId}")
MultipartFile[] download(@PathVariable("fileId") String fileId);
class ClientConfiguration {
@Autowired
private ObjectFactory<HttpMessageConverters> messageConverters;
@Bean
public Decoder feignDecoder () {
List<HttpMessageConverter<?>> springConverters =
messageConverters.getObject().getConverters();
List<HttpMessageConverter<?>> decoderConverters =
new ArrayList<HttpMessageConverter<?>>(springConverters.size() + 1);
decoderConverters.addAll(springConverters);
decoderConverters.add(new SpringManyMultipartFilesReader(4096));
HttpMessageConverters httpMessageConverters = new HttpMessageConverters(decoderConverters);
return new SpringDecoder(new ObjectFactory<HttpMessageConverters>() {
@Override
public HttpMessageConverters getObject() {
return httpMessageConverters;
}
});
}
}
}
