AWS S3 Rest API with Android Retrofit V2 library,

问题:

I'm trying upload a Image from my Android APP to Amazon AWS S3 and I need use AWS Restful API.

I'm using Retrofit 2 to make to the request.

My application is connecting successfully with Amazon S3 and performing the request as expected, but when I try to view the Image from the Bucket, the picture does not open. I downloaded the Image to my pc and tried to open but keep getting the message that the image is corrupted.

Lets see my complete code bellow.

My Gradle dependencies

compile 'com.squareup.retrofit:retrofit:2.0.0-beta1'
compile 'com.squareup.retrofit:converter-gson:2.0.0-beta1'
compile 'net.danlew:android.joda:2.8.2'

Here is created a File and starts the request

File file = new File(mCurrentPhotoPath);
RequestBody body = RequestBody.create(MediaType.parse("image/jpeg"), file);
uploadImage(body, "photo_name.jpeg");

Retrofit Interface

public interface AwsS3 {

    @Multipart
    @PUT("/{Key}")
    Call<String> upload(@Path("Key") String Key,
                @Header("Content-Length") long length,
                @Header("Accept") String accept,
                @Header("Host") String host,
                @Header("Date") String date,
                @Header("Content-type") String contentType,
                @Header("Authorization") String authorization,
                @Part("Body") RequestBody body);
}

Utils class to the mount the credentials

public class AWSOauth {

    public static String getOAuthAWS(Context context, String fileName)  throws Exception{

        String secret = context.getResources().getString(R.string.s3_secret);
        String access = context.getResources().getString(R.string.s3_access_key);
        String bucket = context.getResources().getString(R.string.s3_bucket);

        return gerateOAuthAWS(secret, access, bucket,fileName);
    }

    private static String gerateOAuthAWS(String secretKey, String accessKey, String bucket, String imageName) throws Exception {

        String contentType = "image/jpeg";

        DateTimeFormatter fmt = DateTimeFormat.forPattern("EEE', 'dd' 'MMM' 'yyyy' 'HH:mm:ss' 'Z").withLocale(Locale.US);
        String ZONE = "GMT";
        DateTime dt = new DateTime();
        DateTime dtLondon = dt.withZone(DateTimeZone.forID(ZONE)).plusHours(1);
        String formattedDate = dtLondon.toString(fmt);

        String resource = "/" + bucket + "/" + imageName;

        String stringToSign = "PUT" + "\n\n" + contentType + "\n" + formattedDate + "\n" + resource;

        Mac hmac = Mac.getInstance("HmacSHA1");
        hmac.init(new SecretKeySpec(secretKey.getBytes("UTF-8"), "HmacSHA1"));

        String signature = ( Base64.encodeToString(hmac.doFinal(stringToSign.getBytes("UTF-8")), Base64.DEFAULT)).replaceAll("\n", "");

        String oauthAWS = "AWS " + accessKey + ":" + signature;

        return  oauthAWS;
    }
}

Lastly the method to make a request

 public void uploadImage(RequestBody body, String fileName){

        String bucket = getString(R.string.s3_bucket);

        Retrofit restAdapter = new Retrofit.Builder()
                .baseUrl("http://" + bucket + ".s3.amazonaws.com")
                .addConverterFactory(GsonConverterFactory.create())
                .build();

        AwsS3 service = restAdapter.create(AwsS3.class);

        DateTimeFormatter fmt = DateTimeFormat.forPattern("EEE', 'dd' 'MMM' 'yyyy' 'HH:mm:ss' 'Z").withLocale(Locale.US);
        String ZONE = "GMT";
        DateTime dt = new DateTime();
        DateTime dtLondon = dt.withZone(DateTimeZone.forID(ZONE)).plusHours(1);
        String formattedDate = dtLondon.toString(fmt);

        try {

            String oauth = AWSOauth.getOAuthAWS(getApplicationContext(), fileName);

            Call<String> call = service.upload(fileName, body.contentLength(), "/**", bucket + ".s3.amazonaws.com", formattedDate,  body.contentType().toString(), oauth, body);
            call.enqueue(new Callback<String>() {
                @Override
                public void onResponse(Response<String> response) {
                    Log.d("tag", "response : " + response.body());
                }

                @Override
                public void onFailure(Throwable t) {
                    Log.d("tag", "response : " + t.getMessage());
                }
            });

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

I appreciate any helps, thanks in advance!

回答1:

RequestBody avatarBody = RequestBody.create(MediaType.parse("image"),file);
MultipartBody.Part filePart = MultipartBody.Part.createFormData("file", file.getName(), avatarBody);


@Multipart
@POST(url)
Call<ResponseBody> uploadImageAmazon(
            @Part MultipartBody.Part filePart);

I had same experience, and solved it by https://github.com/square/retrofit/issues/2424 this solution

回答2:

I have the same problem, and as I use Fiddler checked the HTTP request content, I found retrofit 2.0.0 beta1 has a different with 1.9.0.

In my problem, the different of HTTP request content prevent server get the correct data.

In order to make a same HTTP request content, i do next steps using retrofit 2.0.0 deta1.

---

In the retrofit service, add a form-data header for the http request;

@Headers("Content-Type: multipart/form-data;boundary=95416089-b2fd-4eab-9a14-166bb9c5788b")

int retrofit 2.0.0 deta1, the header using @Multipart will get a data like this:

Content-Type: multipart/mixed

as the deafult value is mixed, and has no boundary title.

---

Do not using @Multipart to upload file, just using @Body RequestBody

if you using @Multipart to request Server, you have to pass param(file) through

@Part(key), then a new problem you will get. May be retrofit 2.0.0beta1 has a BUG ..., @Multipart generate a bad http request compile with 1.9.0.

---

When you call the method, you need pass MultipartRequestBody to @Body RequestBody

Using MultipartBuilder to create a MultipartRequestBody, when you new MultipartBuilder, call this consturt:

new MultipartBuilder("95416089-b2fd-4eab-9a14-166bb9c5788b")

the param is you set int @headers(boundary=)

builder.addFormDataPart(String name, String filename, RequestBody value)

This method will help form a data like below int HTTP request content:

Content-Disposition: form-data; name="imgFile"; filename="IMG_20150911_113029.jpg" Content-Type: image/jpg Content-Length: 1179469

RequestBody value is what you has generate in your code.

I just resolve this problem temporary.

Hope can help you!

回答3:

I have used Retrofit 2 resolve
and I use Body instead of Part for your RequestBody in interface

@PUT("")Call<String> nameAPI(@Url String url ,@Body RequestBody body);

and java code

 //prepare image file
 File file = new File(pathImg);
    RequestBody requestBody = RequestBody.create(MediaType.parse("image/jpeg"), file);

    Call<String> call  = SingletonApiServiceS3.getInstance().getService().nameAPI(
            path,
            requestBody
    );
    call.enqueue(new Callback<String>() {
        @Override
        public void onResponse(Call<String> call, final Response<String> response) {

            if (response.isSuccessful()) {



            } else {

            }
        }

        @Override
        public void onFailure(Call<String> call, Throwable t) {

            Toast.makeText(getContext(),"onFailure : "+t.getMessage().toString(),Toast.LENGTH_SHORT).show();
        }
    });

回答4:

You are sending a multipart payload, but forcing the Content-type to be image/jpeg. Your jpg is corrupt because S3 probably saved the multipart headers into your jpg file since you told it the whole message was a JPG. Since you do not actually have multiple parts to send, you can drop the Multipart annotation and use Body instead of Part for your RequestBody

public interface AwsS3 {

    @PUT("/{Key}")
    Call<String> upload(@Path("Key") String Key,
                @Header("Content-Length") long length,
                @Header("Accept") String accept,
                @Header("Host") String host,
                @Header("Date") String date,
                @Header("Content-type") String contentType,
                @Header("Authorization") String authorization,
                @Body RequestBody body);
}

You should also be able to remove explicitly setting the Content-type and Content-length headers.

回答5:

I haven't used Retrofit 2, just Retrofit 1, so YMMV, but I believe that the typical way to do what you're trying to do is to use TypedFile where you are attempting to use RequestBody.

I'm guessing that Retrofit uses RequestBody internally.

You would create the TypedFile something like:

TypedFile typedFile = new TypedFile("multipart/form-data", new File("path/to/your/file"));

and your interface would be:

   @Multipart
    @PUT("/{Key}")
    Call<String> upload(@Path("Key") String Key,
                @Header("Content-Length") long length,
                @Header("Accept") String accept,
                @Header("Host") String host,
                @Header("Date") String date,
                @Header("Content-type") String contentType,
                @Header("Authorization") String authorization,
                @Part("Body") TypedFile body);
}

There's a decent example at https://futurestud.io/blog/retrofit-how-to-upload-files/

回答6:

You can use retrofit 2 to upload the image/file

@Multipart
@POST("/api/attachment")
Call<JsonPrimitive> addAttachment(@Part MultipartBody.Part imageFile);

Now to make the call:

 RequestBody requestBody = RequestBody.create(MediaType.parse("multipart/form-data"), file);
    MultipartBody.Part imageFileBody = MultipartBody.Part.createFormData("file", file.getName(), requestBody);

Note : Make sure you are using retrofit2 as for some reason I was unable to upload image using retrofit1 library.