Uploading image from Android to GCS

Question

I am trying to upload an image from Android directly to Google cloud storage. But the API does not seem to work. They have some Java samples which are tied to the App engine

Answer 1

Hpsaturn's answer worked for me. He missed to answer a few points. How to get service account id and p12 file. For getting these 2, open console.developers.google.com and choose your project. Enable Cloud Storage API. You see a message to create credentials. Go to credentials in API manager and create credential by selecting Service account key and follow the details in image. You will get the service account id and p12 file from this screen.

Hpsaturn also missed to mention AppData, which is your custom Application class defined in manifest. For everyone's convenience, I am attaching the complete CloudStorage class here.

package com.abc.xyz.utils;

import android.net.Uri;
import android.os.Environment;
import android.util.Log;

import com.abc.xyz.app.AppController;
import com.google.api.client.auth.oauth2.Credential;
import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.api.client.http.HttpTransport;
import com.google.api.client.http.InputStreamContent;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.jackson2.JacksonFactory;
import com.google.api.services.storage.Storage;
import com.google.api.services.storage.StorageScopes;
import com.google.api.services.storage.model.StorageObject;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.List;

/**
 * Created by wjose on 8/20/2016.
 */
public class CloudStorage {

    private static final String TAG = "CloudStorage";

    public static void uploadFile(String bucketName, String name, Uri uri)throws Exception {

        Storage storage = getStorage();
        StorageObject object = new StorageObject();
        object.setBucket(bucketName);
        File sdcard = Environment.getExternalStorageDirectory();
        //File file = new File(sdcard,filePath);
        File file = new File(uri.getPath());

        InputStream stream = new FileInputStream(file);

        try {
            String contentType = URLConnection.guessContentTypeFromStream(stream);
            InputStreamContent content = new InputStreamContent(contentType,stream);

            Storage.Objects.Insert insert = storage.objects().insert(bucketName, null, content);
            insert.setName(name);
            StorageObject obj = insert.execute();
            Log.d(TAG, obj.getSelfLink());
        } finally {
            stream.close();
        }
    }

    static Storage storage = null;
    private static Storage getStorage() throws Exception {

        if (storage == null) {
            HttpTransport httpTransport = new NetHttpTransport();
            JsonFactory jsonFactory = new JacksonFactory();
            List scopes = new ArrayList();
            scopes.add(StorageScopes.DEVSTORAGE_FULL_CONTROL);

            Credential credential = new GoogleCredential.Builder()
                    .setTransport(httpTransport)
                    .setJsonFactory(jsonFactory)
                    .setServiceAccountId("myuser-801@xxxyyyzzz.iam.gserviceaccount.com") //Email
                    .setServiceAccountPrivateKeyFromP12File(getTempPkc12File())
                    .setServiceAccountScopes(scopes).build();

            storage = new Storage.Builder(httpTransport, jsonFactory,
                    credential).setApplicationName("MyApp")
                    .build();
        }

        return storage;
    }

    private static File getTempPkc12File() throws IOException {
        // xxx.p12 export from google API console
        InputStream pkc12Stream = MyApplication.getInstance().getAssets().open("xxxyyyzzz-0c80eed2e8aa.p12");
        File tempPkc12File = File.createTempFile("temp_pkc12_file", "p12");
        OutputStream tempFileStream = new FileOutputStream(tempPkc12File);
        int read = 0;
        byte[] bytes = new byte[1024];
        while ((read = pkc12Stream.read(bytes)) != -1) {
            tempFileStream.write(bytes, 0, read);
        }
        return tempPkc12File;
    }
}

btb, I used only following dependency in the gradle.

compile 'com.google.apis:google-api-services-storage:+'