Whole Body Binding

When request part names aren’t known ahead of time, or to read the entire body, a special type can be used to indicate the entire body is desired.

If a route has an argument of type MultipartBody (not to be confused with the class for the client) annotated with @Body, each part of the request will be emitted through the argument. A MultipartBody is a publisher of CompletedPart instances.

For example:

Binding to the entire multipart body

import io.micronaut.http.annotation.Body;
import io.micronaut.http.annotation.Controller;
import io.micronaut.http.annotation.Post;
import io.micronaut.http.multipart.CompletedFileUpload;
import io.micronaut.http.multipart.CompletedPart;
import io.micronaut.http.server.multipart.MultipartBody;
import org.reactivestreams.Publisher;
import org.reactivestreams.Subscriber;
import org.reactivestreams.Subscription;
import reactor.core.publisher.Mono;
import io.micronaut.core.async.annotation.SingleResult;
import static io.micronaut.http.MediaType.MULTIPART_FORM_DATA;
import static io.micronaut.http.MediaType.TEXT_PLAIN;
@Controller("/upload")
public class WholeBodyUploadController {
    @Post(value = "/whole-body", consumes = MULTIPART_FORM_DATA, produces = TEXT_PLAIN) (1)
    @SingleResult
    public Publisher<String> uploadBytes(@Body MultipartBody body) { (2)
        return Mono.create(emitter -> {
            body.subscribe(new Subscriber<CompletedPart>() {
                private Subscription s;
                @Override
                public void onSubscribe(Subscription s) {
                    this.s = s;
                    s.request(1);
                }
                @Override
                public void onNext(CompletedPart completedPart) {
                    String partName = completedPart.getName();
                    if (completedPart instanceof CompletedFileUpload) {
                        String originalFileName = ((CompletedFileUpload) completedPart).getFilename();
                    }
                }
                @Override
                public void onError(Throwable t) {
                    emitter.error(t);
                }
                @Override
                public void onComplete() {
                    emitter.success("Uploaded");
                }
            });
        });
    }
}

Binding to the entire multipart body

import io.micronaut.http.annotation.Body
import io.micronaut.http.annotation.Controller
import io.micronaut.http.annotation.Post
import io.micronaut.http.multipart.CompletedFileUpload
import io.micronaut.http.multipart.CompletedPart
import io.micronaut.http.server.multipart.MultipartBody
import org.reactivestreams.Subscriber
import org.reactivestreams.Subscription
import reactor.core.publisher.Mono
import static io.micronaut.http.MediaType.MULTIPART_FORM_DATA
import static io.micronaut.http.MediaType.TEXT_PLAIN
@Controller("/upload")
class WholeBodyUploadController {
    @Post(value = "/whole-body", consumes = MULTIPART_FORM_DATA, produces = TEXT_PLAIN) (1)
    Mono<String> uploadBytes(@Body MultipartBody body) { (2)
        Mono.<String>create({ emitter ->
            body.subscribe(new Subscriber<CompletedPart>() {
                private Subscription s
                @Override
                void onSubscribe(Subscription s) {
                    this.s = s
                    s.request(1)
                }
                @Override
                void onNext(CompletedPart completedPart) {
                    String partName = completedPart.name
                    if (completedPart instanceof CompletedFileUpload) {
                        String originalFileName = completedPart.filename
                    }
                }
                @Override
                void onError(Throwable t) {
                    emitter.error(t)
                }
                @Override
                void onComplete() {
                    emitter.success("Uploaded")
                }
            })
        })
    }
}

Binding to the entire multipart body

import io.micronaut.http.MediaType.MULTIPART_FORM_DATA
import io.micronaut.http.MediaType.TEXT_PLAIN
import io.micronaut.http.annotation.Body
import io.micronaut.http.annotation.Controller
import io.micronaut.http.annotation.Post
import io.micronaut.http.multipart.CompletedFileUpload
import io.micronaut.http.multipart.CompletedPart
import io.micronaut.http.server.multipart.MultipartBody
import org.reactivestreams.Subscriber
import org.reactivestreams.Subscription
import reactor.core.publisher.Mono
@Controller("/upload")
class WholeBodyUploadController {
    @Post(value = "/whole-body", consumes = [MULTIPART_FORM_DATA], produces = [TEXT_PLAIN]) (1)
    fun uploadBytes(@Body body: MultipartBody): Mono<String> { (2)
        return Mono.create { emitter ->
            body.subscribe(object : Subscriber<CompletedPart> {
                private var s: Subscription? = null
                override fun onSubscribe(s: Subscription) {
                    this.s = s
                    s.request(1)
                }
                override fun onNext(completedPart: CompletedPart) {
                    val partName = completedPart.name
                    if (completedPart is CompletedFileUpload) {
                        val originalFileName = completedPart.filename
                    }
                }
                override fun onError(t: Throwable) {
                    emitter.error(t)
                }
                override fun onComplete() {
                    emitter.success("Uploaded")
                }
            })
        }
    }
}