Retrofit: How to upload array of images as a Part of multipart request?

[lashket]

I must send multipart request in which one part is array of images.
For example:

{
    "name": "Frying Pan Tower",
  "lat": 33.747358867853706,
  "lng": -77.92252913117409,
  "depth": 15.24,
  "images[]" - to this field i need paste a array of images
}

I'm using Retrofit 2.0.1

For one image i create something like this, and it's work fine for me

    @Multipart
    Call<ResponseBody> add(
            @Part("name") RequestBody name,
            @Part("distribution") RequestBody distribution,
            @Part("habitat") RequestBody habitat,
            @Part MultipartBody.Part image);

[JakeWharton]

You can use @Part List<MultipartBody.Part> images for a runtime-defined number of parts.

[Tooto]

@lashket hi! May you say, how you solved your problem? I cant send list of images :(

[mengmengmengmeng]

hi @JakeWharton, I also tried this approach

@Multipart @POST(Endpoints.BASE_URL + Endpoints.EVENTS) Call<ResponseBody> createTrip(@Header("Authorization") String header, @Part("access_token") String access, @Part List<MultipartBody.Part> photos, @Part("name") RequestBody trip_name, @Part("start_at") RequestBody start_at, @Part("end_at") RequestBody end_at, @Part("downpayment_rate") RequestBody downpayment, @Part("booking_fee") RequestBody booking_fee, @Part("meeting_place") RequestBody meeting_place, @Part List<MultipartBody.Part> itinerary, @Part("min_pax") RequestBody min_pax, @Part("max_pax") RequestBody max_pax, @Part("lat") RequestBody lat, @Part("lng") RequestBody lng);

@Part List<MultipartBody.Part> itinerary is actually working but @Part List<MultipartBody.Part> photos is not.

This is how I created them

for (int i = 0; i < coverImages.size(); i++) { File file = new File(coverImages.get(i).path); RequestBody requestBody = RequestBody.create(MediaType.parse("image/*"), file); MultipartBody.Part filePart = MultipartBody.Part.createFormData("photos[]", file.getName(), requestBody); photos.add(filePart); }

    `for (int i = 0; i < etListItinerary.size(); i++) {
        MultipartBody.Part part = MultipartBody.Part.createFormData("itineraries_description[]", etListItinerary.get(i).getText().toString());
        itineraries_description.add(part);
    }`

[agustinparamio]

@mengmengmengmeng did you manage to resolve this issue? i'm having troubles to send a header, a json object and an array of images to my API. My code looks very similar to yours, did it worked?

[alex8530]

hi there , if any one still couldn't solve this issue ,,, try this
@Multipart
Call add(
@Part("name") RequestBody name,
@Part("distribution") RequestBody distribution,
@Part("habitat") RequestBody habitat,
@Part MultipartBody.Part image,
@Part List images
);

[castrojr913]

You can use @Part List<MultipartBody.Part> images for a runtime-defined number of parts.

@JakeWharton @alex8530 it seems there is a constraint up to 20 images in order to upload. I've tried to send a HTTP request with more than 20 attached images as multipart-data through com.squareup.retrofit2:retrofit:2.2.0 and com.squareup.okhttp3:logging-interceptor:3.4.1

[JakeWharton]

There is no constraint in either Retrofit or OkHttp so anything imposed will be done by the target server.