When you upload part of a large file to B2, you must call b2_get_upload_part_url first to get the URL for uploading. Then, you use b2_upload_part on this URL to upload your data.

An uploadUrl and upload authorizationToken are valid for 24 hours or until the endpoint rejects an upload, see b2_upload_file. You can upload as many files to this URL as you need. To achieve faster upload speeds, request multiple uploadUrls and upload your files to these different endpoints in parallel.

Request

Request HTTP Headers

Authorization

required

An account authorization token, obtained from b2_authorize_account. The token must have the writeFiles capability.

Request HTTP Message Body Parameters

fileId

required

The ID of the large file whose parts you want to upload.

Response

Response HTTP Status 200

Information for uploading file parts. The JSON response will contain:

fileId

The unique ID of file being uploaded.

uploadUrl

The URL that can be used to upload parts of this file, see b2_upload_part.

authorizationToken

The authorizationToken that must be used when uploading files with this URL. This token is valid for 24 hours or until the uploadUrl endpoint rejects an upload, see b2_upload_part

Response Errors

If possible the server will return a JSON error structure. Errors include:

status	code	description
400	bad_bucket_id	The requested bucket ID does not match an existing bucket.
400	bad_request	The request had the wrong fields or illegal values. The message returned with the error will describe the problem.
400	cannot_delete_non_empty_bucket	A bucket must be empty before it can be deleted. To delete this bucket, first remove all of the files in the bucket, then try the delete operation again.
401	bad_auth_token	The auth token used is not valid. Call b2_authorize_account again to either get a new one, or an error message describing the problem.
401	expired_auth_token	The auth token used has expired. Call b2_authorize_account again to get a new one.
401	unauthorized	The auth token used is valid, but does not authorize this call with these parameters. The capabilities of an auth token are determined by the application key used with b2_authorize_account.
403	storage_cap_exceeded	Usage cap exceeded.
503	service_unavailable	No uploads available in vault <vaultId>

API Versions

v1: Application keys (July 26, 2018)

Incompatible change: After calling b2_authorize_account with an application key that does not have the right permissions, this call will return a 401 Unauthorized.

v1: Original release (September 22, 2015)

Sample Code

Code

FILE_ID=''; # Provided by b2_start_large_file
ACCOUNT_AUTHORIZATION_TOKEN=''; # Provided by b2_authorize_account
API_URL=''; # Provided by b2_authorize_account
curl \
    -H "Authorization: $ACCOUNT_AUTHORIZATION_TOKEN" \
    -d "`printf '{"fileId":"%s"}' $FILE_ID`" \
    "$API_URL/b2api/v2/b2_get_upload_part_url"

Output

{
  "authorizationToken": "3_20160409004829_42b8f80ba60fb4323dcaad98_ec81302316fccc2260201cbf17813247f312cf3b_000_uplg",
  "fileId": "4_ze73ede9c9c8412db49f60715_f100b4e93fbae6252_d20150824_m224353_c900_v8881000_t0001",
  "uploadUrl": "https://pod-000-1016-09.backblaze.com/b2api/v2/b2_upload_part/4_ze73ede9c9c8412db49f60715_f100b4e93fbae6252_d20150824_m224353_c900_v8881000_t0001/0037"
}

Code

import java.io.*;
import java.util.*;
import java.net.HttpURLConnection;
import java.net.URL;
import javax.json.*;

String fileId = ""; // Provided by b2_start_large_file
String accountAuthorizationToken = ""; // Provided by b2_authorize_account
String apiUrl = ""; // Provided by b2_authorize_account

// Get Upload Part URL
// Create a model
JsonObject getUploadPartJsonObj = Json.createObjectBuilder()
        .add("fileId", fileId)
        .build();

// Write the model to stream
StringWriter sw = new StringWriter();
JsonWriter jw = Json.createWriter(sw);
jsonWriter.writeObject(getUploadPartJsonObj);
jsonWriter.close();
postData = sw.toString();
try {
    URL url = new URL(apiUrl + "/b2api/v2/b2_get_upload_part_url");
    connection = (HttpURLConnection)url.openConnection();
    connection.setRequestMethod("POST");
    connection.setRequestProperty("Authorization", accountAuthorizationToken);
    connection.setRequestProperty("Content-Type", "application/json");
    connection.setRequestProperty("Charset", "UTF-8");
    connection.setRequestProperty("Content-Length", Integer.toString(postData.length()));
    connection.setDoOutput(true);
    DataOutputStream dataOutputStream = new DataOutputStream(connection.getOutputStream());
    dataOutputStream.writeBytes(postData);
    dataOutputStream.close();
    String jsonResponse = myInputStreamReader(connection.getInputStream());
    System.out.println(jsonResponse);
} catch (Exception e) {
    e.printStackTrace();
} finally {
    connection.disconnect();
}

// Input stream reader example. 
static public String myInputStreamReader(InputStream in) throws IOException {
    InputStreamReader reader = new InputStreamReader(in);
    StringBuilder sb = new StringBuilder();
    int c = reader.read();
    while (c != -1) {
        sb.append((char)c);
        c = reader.read();
    }
    reader.close();
    return sb.toString();
}

Output

{
  "authorizationToken": "3_20160409004829_42b8f80ba60fb4323dcaad98_ec81302316fccc2260201cbf17813247f312cf3b_000_uplg",
  "fileId": "4_ze73ede9c9c8412db49f60715_f100b4e93fbae6252_d20150824_m224353_c900_v8881000_t0001",
  "uploadUrl": "https://pod-000-1016-09.backblaze.com/b2api/v2/b2_upload_part/4_ze73ede9c9c8412db49f60715_f100b4e93fbae6252_d20150824_m224353_c900_v8881000_t0001/0037"
}

Code

import base64
import json
import urllib2

file_id = "" # Provided by b2_start_large_file
request = urllib2.Request(
    '%s/b2api/v2/b2_get_upload_part_url' % api_url,
    json.dumps({ 'fileId' : file_id }),
    headers = { 'Authorization': account_authorization_token }
)
response = urllib2.urlopen(request)
response_data = json.loads(response.read())
response.close()

Output

{
  "authorizationToken": "3_20160409004829_42b8f80ba60fb4323dcaad98_ec81302316fccc2260201cbf17813247f312cf3b_000_uplg",
  "fileId": "4_ze73ede9c9c8412db49f60715_f100b4e93fbae6252_d20150824_m224353_c900_v8881000_t0001",
  "uploadUrl": "https://pod-000-1016-09.backblaze.com/b2api/v2/b2_upload_part/4_ze73ede9c9c8412db49f60715_f100b4e93fbae6252_d20150824_m224353_c900_v8881000_t0001/0037"
}

Code

import Foundation

let apiUrl = "" // Provided by b2_authorize_account
let fileId = "" // The file ID provided by b2_start_large_file
let accountAuthorizationToken = "" // Provided by b2_authorize_account

// Create the request
var request = URLRequest(url: URL(string: "\(apiUrl)/b2api/v2/b2_get_upload_part_url")!)
request.httpMethod = "POST"
request.addValue( accountAuthorizationToken, forHTTPHeaderField: "Authorization")
request.httpBody = "{\"fileId\":\"\(fileId)\"}".data(using: .utf8)

// Create the task
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
	if let data = data {
		let json = String(data: data, encoding: .utf8)
		print("\(json!)")
	}
}

// Start the task
task.resume()

// Swift 4.1 (swiftlang-902.0.48 clang-902.0.37.1) Xcode 9.3.1 (9E501)

Output

{
  "authorizationToken": "3_20160409004829_42b8f80ba60fb4323dcaad98_ec81302316fccc2260201cbf17813247f312cf3b_000_uplg",
  "fileId": "4_ze73ede9c9c8412db49f60715_f100b4e93fbae6252_d20150824_m224353_c900_v8881000_t0001",
  "uploadUrl": "https://pod-000-1016-09.backblaze.com/b2api/v2/b2_upload_part/4_ze73ede9c9c8412db49f60715_f100b4e93fbae6252_d20150824_m224353_c900_v8881000_t0001/0037"
}

Code

require 'json'
require 'net/http'

api_url = "" # Provided by b2_authorize_account
file_id = "" # Provided by b2_start_large_file
account_authorization_token = "" # Provided by b2_authorize_account
uri = URI.join("#{api_url}/b2api/v2/b2_get_upload_part_url")
req = Net::HTTP::Post.new(uri)
req.add_field("Authorization","#{account_authorization_token}")
req.body = "{\"fileId\":\"#{file_id}\"}"
http = Net::HTTP.new(req.uri.host, req.uri.port)
http.use_ssl = true
res = http.start {|http| http.request(req)}
case res
when Net::HTTPSuccess then
    res.body
when Net::HTTPRedirection then
    fetch(res['location'], limit - 1)
else
    res.error!
end

Output

{
  "authorizationToken": "3_20160409004829_42b8f80ba60fb4323dcaad98_ec81302316fccc2260201cbf17813247f312cf3b_000_uplg",
  "fileId": "4_ze73ede9c9c8412db49f60715_f100b4e93fbae6252_d20150824_m224353_c900_v8881000_t0001",
  "uploadUrl": "https://pod-000-1016-09.backblaze.com/b2api/v2/b2_upload_part/4_ze73ede9c9c8412db49f60715_f100b4e93fbae6252_d20150824_m224353_c900_v8881000_t0001/0037"
}

Code

using System;
using System.Net;
using System.Text;
using System.IO;
using System.Runtime.Serialization.Json;
using System.Runtime.Serialization;

String apiUrl = ""; // Provided by b2_authorize_account
String fileId = ""; // Provided by b2_start_large_file
String authorizationToken = ""; // Provided by b2_authorize_account

// Get Upload URL
String getUploadUrlJsonStr = "{\"fileId\":\"" + fileId + "\"}";
byte[] getUloadUrlJsonData = Encoding.UTF8.GetBytes(getUploadUrlJsonStr);
HttpWebRequest getUploadUrlRequest = (HttpWebRequest)WebRequest.Create(apiUrl + "/b2api/v2/b2_get_upload_part_url");
getUploadUrlRequest.Method = "POST";
getUploadUrlRequest.Headers.Add("Authorization", authorizationToken);
getUploadUrlRequest.ContentType = "application/json; charset=utf-8";
getUploadUrlRequest.ContentLength = getUloadUrlJsonData.Length;
using (Stream stream = getUploadUrlRequest.GetRequestStream())
{
    stream.Write(getUloadUrlJsonData, 0, getUloadUrlJsonData.Length);
    stream.Close();
}

// Handle the response and print the json
try
{
    HttpWebResponse getUploadUrlResponse = (HttpWebResponse)getUploadUrlRequest.GetResponse();
	using(StringReader responseReader = new StreamReader(getUploadUrlResponse.GetResponseStream()))
    {
    	String json = responseReader.ReadToEnd();
    	Console.WriteLine(json);
    }
    getUploadUrlResponse.Close();    
}
catch (WebException e)
{
    using (HttpWebResponse errorResponse = (HttpWebResponse)e.Response)
    {
        Console.WriteLine("Error code: {0}", errorResponse.StatusCode);
        using (StreamReader reader = new StreamReader(errorResponse.GetResponseStream()))
        {
            String text = reader.ReadToEnd();
            Console.WriteLine(text);
        }
    }
}

Output

under construction

Code

<?php

$file_id = "" // Obtained from b2_start_large_file
$account_auth_token = "" // Obtained from b2_authorize_account
$data = array("fileId" => $file_id);
$post_fields = json_encode($data);

// Setup headers
$headers = array();
$headers[] = "Accept: application/json";
$headers[] = "Authorization: " . $account_auth_token;

//  Setup curl to do the post
$session = curl_init($api_url . "/b2api/v2/b2_get_upload_part_url");
curl_setopt($session, CURLOPT_HTTPHEADER, $headers);  // Add headers
curl_setopt($session, CURLOPT_POSTFIELDS, $post_fields); 
curl_setopt($session, CURLOPT_RETURNTRANSFER, true); // Receive server response
$server_output = curl_exec($session);
curl_close ($session);
print $server_output;

?>

Output

{
  "authorizationToken": "3_20160409004829_42b8f80ba60fb4323dcaad98_ec81302316fccc2260201cbf17813247f312cf3b_000_uplg",
  "fileId": "4_ze73ede9c9c8412db49f60715_f100b4e93fbae6252_d20150824_m224353_c900_v8881000_t0001",
  "uploadUrl": "https://pod-000-1016-09.backblaze.com/b2api/v2/b2_upload_part/4_ze73ede9c9c8412db49f60715_f100b4e93fbae6252_d20150824_m224353_c900_v8881000_t0001/0037"
}