Android™

Download a File from a SharePoint Documents Library

See more SharePoint Examples

This example shows how to use Chilkat's HttpCurl class to download a file from the root of a SharePoint Documents document library. The example demonstrates how HttpCurl automatically resolves the SharePoint site name to a site ID, finds the drive ID for the Documents library, locates the file by name, and then downloads the file content using Microsoft Graph.

Android™

// 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);

    boolean success = false;

    //  This example downloads a file named "hamlet.json" from the root of the SharePoint
    //  Documents document library.
    //  
    //  The example demonstrates how HttpCurl can automatically resolve all of the
    //  information needed to locate and download a file:
    //  
    //    site_name            -> site_id
    //    site_id              -> document_library_id
    //    document_library_id  -> file_id
    //    file_id              -> file content
    //  
    //  The application only provides the SharePoint site name and the desired
    //  filename.  HttpCurl automatically executes the required Microsoft Graph
    //  requests to obtain the remaining values.

    success = false;

    //  --------------------------------------------------------------------------------------------------------
    //  Before running this example, create an Azure App Registration and grant it
    //  the Microsoft Graph permissions required to access SharePoint.
    //  
    //  The application will authenticate using OAuth2 Client Credentials.
    //  See:
    //  How to Create SharePoint App Registration for OAuth 2.0 Client Credentials
    //  --------------------------------------------------------------------------------------------------------

    //  Build a JSON authentication configuration.
    //  HttpCurl will use this information to automatically obtain OAuth2 access tokens.
    CkJsonObject jsonAuth = new CkJsonObject();

    //  Enable secret lookup.
    //  
    //  Instead of hard-coding sensitive values such as the client ID,
    //  client secret, and token endpoint, secret specification strings
    //  are used.  Chilkat automatically retrieves the actual values from
    //  Windows Credential Manager (Windows) or Apple Keychain (macOS).
    //  
    //  See:
    //  Secret Specification Strings
    jsonAuth.put_EnableSecrets(true);

    success = jsonAuth.UpdateString("oauth2.client_id","!!sharepoint|oauth2|client_id");
    if (success == true) {
        success = jsonAuth.UpdateString("oauth2.client_secret","!!sharepoint|oauth2|client_secret");
        }

    if (success == true) {
        success = jsonAuth.UpdateString("oauth2.token_endpoint","!!sharepoint|oauth2|token_endpoint");
        }

    if (success == false) {
        Log.i(TAG, jsonAuth.lastErrorText());
        return;
        }

    //  Request Microsoft Graph permissions that were granted to the application.
    jsonAuth.UpdateString("oauth2.scope","https://graph.microsoft.com/.default");

    //  ---------------------------------------------------------------------------------------------------

    CkHttpCurl curl = new CkHttpCurl();

    //  Associate the OAuth2 configuration with HttpCurl.
    //  
    //  When the request is executed, Chilkat automatically obtains an access token
    //  if needed and adds the Authorization: Bearer header to the HTTP request.
    curl.SetAuth(jsonAuth);

    //  Define values that are already known.
    //  
    //  These variables are referenced in curl commands using
    //  {{variable_name}} substitution syntax.
    curl.SetVar("sharepoint_hostname","example.sharepoint.com");
    curl.SetVar("site_name","test");

    //  The first step is to obtain the Microsoft Graph site ID.
    //  
    //  The application only knows the SharePoint site name, so define
    //  a function that can retrieve the site information.
    curl.AddFunction("getSite","GET https://graph.microsoft.com/v1.0/sites/root:/sites/{{site_name}}");

    //  Extract the site's ID and store it in the HttpCurl variable named site_id.
    curl.AddOutput("getSite","id","site_id");

    //  The next step is to find the Documents document library.
    //  
    //  Microsoft Graph refers to document libraries as "drives".
    curl.AddFunction("getDrives","GET https://graph.microsoft.com/v1.0/sites/{{site_id}}/drives");

    //  Search the returned drives for the one named "Documents"
    //  and save its drive ID in the document_library_id variable.
    curl.AddOutput2("getDrives","value","name","Documents",true,"id","document_library_id");

    //  Now list the contents of the Documents document library.
    curl.AddFunction("getFiles","GET https://graph.microsoft.com/v1.0/sites/{{site_id}}/drives/{{document_library_id}}/root/children");

    //  Search the returned files for an item named "hamlet.json"
    //  and save its Microsoft Graph item ID in the file_id variable.
    curl.AddOutput2("getFiles","value","name","hamlet.json",true,"id","file_id");

    //  This is the target request.
    //  
    //  GET -L https://graph.microsoft.com/v1.0/drives/{{document_library_id}}/items/{{file_id}}/content
    //  
    //  The /content endpoint returns the actual contents of the file.
    //  
    //  The -L option instructs HttpCurl to follow the redirect returned by
    //  Microsoft Graph.  The Graph API typically responds with a redirect
    //  to the actual file download URL.
    String curlCommand = "GET -L https://graph.microsoft.com/v1.0/drives/{{document_library_id}}/items/{{file_id}}/content";

    //  Execute the request.
    //  
    //  HttpCurl examines the target request and determines that both
    //  document_library_id and file_id are required.
    //  
    //  To obtain these values, it automatically builds and executes
    //  the following dependency chain:
    //  
    //    1) getSite      -> site_id
    //    2) getDrives    -> document_library_id
    //    3) getFiles     -> file_id
    //    4) download     -> file content
    //  
    //  The final response returned by DoYourThing is the downloaded
    //  file content from the target request.
    success = curl.DoYourThing(curlCommand);
    if (success == false) {
        Log.i(TAG, curl.lastErrorText());
        return;
        }

    //  A successful Graph response should return HTTP 200.
    //  Any other status code typically indicates an authentication,
    //  permission, site lookup, document library lookup, or file lookup error.
    int statusCode = curl.get_StatusCode();
    if (statusCode != 200) {
        Log.i(TAG, curl.responseBodyStr());
        Log.i(TAG, "status code = " + String.valueOf(statusCode));
        return;
        }

    //  The response body contains the contents of the downloaded file.
    CkStringBuilder sbFileContents = new CkStringBuilder();
    curl.GetResponseSb(sbFileContents);

    //  Optionally save the downloaded content to a local file.
    //  
    //  The third argument controls whether the file is appended.
    //  Passing ckfalse causes the file to be overwritten if it already exists.
    success = sbFileContents.WriteFile("c:/temp/hamlet.json","utf-8",false);
    if (success == false) {
        Log.i(TAG, sbFileContents.lastErrorText());
        return;
        }

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

  }

  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."
  }
}