(Android™) Download Object from Google Cloud Storage

Demonstrates how to download an object from Google Cloud Storage to a file.

Chilkat Android™ Downloads Android™ Java Libraries Android C/C++ Libraries

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // This example uses a previously obtained access token having permission for the 
    // scope "https://www.googleapis.com/auth/cloud-platform"

    // In this example, Get Google Cloud Storage OAuth2 Access Token, 
    // the service account access token was saved to a text file.  This example fetches the access token from the file..
    CkStringBuilder sbToken = new CkStringBuilder();
    sbToken.LoadFile("qa_data/tokens/googleCloudStorageAccessToken.txt","utf-8");

    // Send a GET equivalent to this curl command.

    // curl -X GET \
    //     -H "Authorization: Bearer [OAUTH2_TOKEN]" \
    //     -o "[SAVE_TO_LOCATION]" \
    //     "https://www.googleapis.com/storage/v1/b/[BUCKET_NAME]/o/[OBJECT_NAME]?alt=media"

    CkHttp http = new CkHttp();

    http.put_AuthToken(sbToken.getAsString());

    // Construct a URL to download an object named "starfish.jpg" from the "chilkat-ocean" bucket.
    http.SetUrlVar("bucket_name","chilkat-ocean");
    http.SetUrlVar("object_name","starfish.jpg");
    String url = "https://www.googleapis.com/storage/v1/b/{$bucket_name}/o/{$object_name}?alt=media";

    // If there is an error response, then we didn't actually download the file data,
    // but instead we downloaded an error response..
    CkBinData fileData = new CkBinData();
    boolean success = http.DownloadBd(url,fileData);
    if (success == false) {
        Log.i(TAG, http.lastErrorText());
        return;
        }

    CkStringBuilder sbErrorResponse = new CkStringBuilder();
    int responseCode = http.get_LastStatus();
    if (responseCode == 401) {
        Log.i(TAG, "If invalid credentials, then it is likely the access token expired.");
        Log.i(TAG, "Your app should automatically fetch a new access token and re-try.");
        }

    if (responseCode != 200) {
        // Get the error response
        sbErrorResponse.AppendBd(fileData,"utf-8",0,0);
        Log.i(TAG, "Error response code = " + String.valueOf(responseCode));
        Log.i(TAG, "Error:");
        Log.i(TAG, sbErrorResponse.getAsString());
        return;
        }

    Log.i(TAG, "Success.");

    // Save the downloaded data to a file.
    success = fileData.WriteFile("qa_output/starfish.jpg");

  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}