Lists all of the versions of all of the files contained in one bucket, in alphabetical order by file name, and by reverse of date/time uploaded for versions of files with the same name.

This call returns at most 1000 file names per transaction, but it can be called repeatedly to scan through all of the file names in a bucket. Each time you call, it returns a "nextFileName" and "nextFileId" that can be used as the starting point for the next call.

This call supports the same options for matching a file name prefix and for grouping files into folders as b2_list_file_names. See that page for more details.

The application key you authorized with may restrict access to some files. See b2_list_file_names for details.

Request

Request HTTP Headers

Authorization

required

The account authorization token returned by b2_authorize_account. The token must have the listFiles capability.

Request HTTP Message Body Parameters

bucketId

required

The bucket to look for file names in.

startFileName

optional

The first file name to return.
If there are no files with this name, the first version of the file with the first name after the given name will be the first in the list.
If startFileId is also specified, the name-and-id pair is the starting point. If there is a file with the given name and ID, it will be first in the list. Otherwise, the first file version that comes after the given name and ID will be first in the list.

startFileId

optional

The first file ID to return. startFileName must also be provided if startFileId is specified. (See startFileName.)

maxFileCount

optional

The maximum number of files to return from this call. The default value is 100, and the maximum is 10000. Passing in 0 means to use the default of 100.
NOTE: b2_list_file_versions is a Class C transaction (see Pricing). The maximum number of files returned per transaction is 1000. If you set maxFileCount to more than 1000 and more than 1000 are returned, the call will be billed as multiple transactions, as if you had made requests in a loop asking for 1000 at a time. For example: if you set maxFileCount to 10000 and 3123 items are returned, you will be billed for 4 Class C transactions.

prefix

optional

Files returned will be limited to those with the given prefix. Defaults to the empty string, which matches all files.

delimiter

optional

Files returned will be limited to those within the top folder, or any one subfolder. Defaults to NULL. Folder names will also be returned. The delimiter character will be used to "break" file names into folders.

Response

Response HTTP Status 200

List of file names as JSON:

files

An array of objects, each one describing one file. (See below.)

nextFileName

What to pass in to startFileName for the next search to continue where this one left off, or null if there are no more files. Note this this may not be the name of an actual file, but using it is guaranteed to find the next file version in the bucket.

nextFileId

What to pass in to startFileId for the next search to continue where this one left off, or null if there are no more files. Note this this may not be the ID of an actual file, but using it is guaranteed to find the next file version in the bucket.

And each of the files is:

accountId

The account that owns the file.

action

One of "start", "upload", "hide", "folder", or other values added in the future. "upload" means a file that was uploaded to B2 Cloud Storage. "start" means that a large file has been started, but not finished or canceled. "hide" means a file version marking the file as hidden, so that it will not show up in b2_list_file_names. "folder" is used to indicate a virtual folder when listing files.

bucketId

The bucket that the file is in.

contentLength

The number of bytes stored in the file. Only useful when the action is "upload". Always 0 when the action is "start", "hide", or "folder".

contentSha1

The SHA1 of the bytes stored in the file as a 40-digit hex string. Large files do not have SHA1 checksums, and the value is "none". The value is null when the action is "hide" or "folder".

contentType

When the action is "upload" or "start", the MIME type of the file, as specified when the file was uploaded. For "hide" action, always "application/x-bz-hide-marker". For "folder" action, always null.

fileId

The unique identifier for this version of this file. Used with b2_get_file_info, b2_download_file_by_id, and b2_delete_file_version. The value is null when for action "folder".

fileInfo

The custom information that was uploaded with the file. This is a JSON object, holding the name/value pairs that were uploaded with the file.

fileName

The name of this file, which can be used with b2_download_file_by_name.

uploadTimestamp

This is a UTC time when this file was uploaded. It is a base 10 number of milliseconds since midnight, January 1, 1970 UTC. This fits in a 64 bit integer such as the type "long" in the programming language Java. It is intended to be compatible with Java's time long. For example, it can be passed directly into the java call Date.setTime(long time).
Always 0 when the action is "folder".

Response Errors

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

status	code	description
400	bad_request	The request had the wrong fields or illegal values. The message returned with the error will describe the problem.
400	invalid_bucket_id	Invalid bucketId: <bucketId>
400	out_of_range	maxFileCount out of range: <maxFileCount>
400	invalid_file_id	Invalid startFileId: <startFileId>
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.
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.
503	bad_request	Timed out while iterating and skipping files

API Versions

v2: Remove application key workaround (Sept 13, 2018)

Listing file names will always return all of the file names you ask for. If your application key has a file name prefix restriction, and you ask for files outside that prefix, the call is unauthorized.

Now returns accountId and bucketId. Does not return size any more; use contentLength instead.

v1: Workaround for existing applications and application keys (August 9, 2018)

When using an application key with a file name prefix restriction, a request to list files will be filtered to show only files allowed by the application key.

v1: Original release (September 22, 2015)

Original release.

Sample Code

Code

curl \
    -H 'Authorization: ACCOUNT_AUTHORIZATION_TOKEN' \
    -d '{"bucketId": "BUCKET_ID"} \
    https://apiNNN.backblazeb2.com/b2api/v2/b2_list_file_versions

Output

{
  "files": [
    {
      "accountId": "ACCOUNT_ID",
      "action": "hide",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 0,
      "contentSha1": null,
      "contentType": null,
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10305b68895d22f4_d20180914_m221207_c002_v0001108_t0029",
      "fileInfo": {},
      "fileName": "logscript.py",
      "uploadTimestamp": 1536963127000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 5060,
      "contentSha1": "28e355c532ff4ebcb78337593a2ef9890bd4af7e",
      "contentType": "application/octet-stream",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f1162979affbeac79_d20180914_m210813_c002_v0001107_t0011",
      "fileInfo": {
        "src_last_modified_millis": "1532626031627"
      },
      "fileName": "logscript.py",
      "uploadTimestamp": 1536959293000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 7,
      "contentSha1": "dc724af18fbdd4e59189f5fe768a5f8311527050",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10904e5ca06493a1_d20180914_m223119_c002_v0001094_t0002",
      "fileInfo": {
        "src_last_modified_millis": "1536964184056"
      },
      "fileName": "testing.txt",
      "uploadTimestamp": 1536964279000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 8,
      "contentSha1": "596b29ec9afea9e461a20610d150939b9c399d93",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10076875fe98d4af_d20180914_m223128_c002_v0001108_t0050",
      "fileInfo": {
        "src_last_modified_millis": "1536964200750"
      },
      "fileName": "testing2.txt",
      "uploadTimestamp": 1536964288000
    }
  ],
  "nextFileId": null,
  "nextFileName": null
}

Code

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

String apiUrl = ""; // Provided by b2_authorize_account
String accountAuthorizationToken = ""; // Provided by b2_authorize_account
String bucketId = ""; // The ID of the bucket you are querying
HttpURLConnection connection = null;
String postParams = "{\"bucketId\":\"" + bucketId + "\"}";
byte postData[] = postParams.getBytes(StandardCharsets.UTF_8);
try {
    URL url = new URL(apiUrl + "/b2api/v2/b2_list_file_versions");
    connection = (HttpURLConnection)url.openConnection();
    connection.setRequestMethod("POST");
    connection.setRequestProperty("Authorization", accountAuthorizationToken);
    connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
    connection.setRequestProperty("charset", "utf-8");
    connection.setRequestProperty("Content-Length", Integer.toString(postData.length));
    connection.setDoOutput(true);
    DataOutputStream writer = new DataOutputStream(connection.getOutputStream());
    writer.write(postData);
    String jsonResponse = myInputStreamReader(connection.getInputStream());
    System.out.println(jsonResponse);
} catch (Exception e) {
    e.printStackTrace();
} finally {
    connection.disconnect();
}

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

{
  "files": [
    {
      "accountId": "ACCOUNT_ID",
      "action": "hide",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 0,
      "contentSha1": null,
      "contentType": null,
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10305b68895d22f4_d20180914_m221207_c002_v0001108_t0029",
      "fileInfo": {},
      "fileName": "logscript.py",
      "uploadTimestamp": 1536963127000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 5060,
      "contentSha1": "28e355c532ff4ebcb78337593a2ef9890bd4af7e",
      "contentType": "application/octet-stream",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f1162979affbeac79_d20180914_m210813_c002_v0001107_t0011",
      "fileInfo": {
        "src_last_modified_millis": "1532626031627"
      },
      "fileName": "logscript.py",
      "uploadTimestamp": 1536959293000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 7,
      "contentSha1": "dc724af18fbdd4e59189f5fe768a5f8311527050",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10904e5ca06493a1_d20180914_m223119_c002_v0001094_t0002",
      "fileInfo": {
        "src_last_modified_millis": "1536964184056"
      },
      "fileName": "testing.txt",
      "uploadTimestamp": 1536964279000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 8,
      "contentSha1": "596b29ec9afea9e461a20610d150939b9c399d93",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10076875fe98d4af_d20180914_m223128_c002_v0001108_t0050",
      "fileInfo": {
        "src_last_modified_millis": "1536964200750"
      },
      "fileName": "testing2.txt",
      "uploadTimestamp": 1536964288000
    }
  ],
  "nextFileId": null,
  "nextFileName": null
}

Code

import json
import urllib2

api_url = "" # Provided by b2_authorize_account
account_authorization_token = "" # Provided by b2_authorize_account
bucket_id = "" # The ID of the bucket you are querying
request = urllib2.Request(
	'%s/b2api/v2/b2_list_file_versions' % api_url,
	json.dumps({ 'bucketId' : bucket_id }),
	headers = { 'Authorization': account_authorization_token }
	)
response = urllib2.urlopen(request)
response_data = json.loads(response.read())
response.close()

Output

{
  "files": [
    {
      "accountId": "ACCOUNT_ID",
      "action": "hide",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 0,
      "contentSha1": null,
      "contentType": null,
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10305b68895d22f4_d20180914_m221207_c002_v0001108_t0029",
      "fileInfo": {},
      "fileName": "logscript.py",
      "uploadTimestamp": 1536963127000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 5060,
      "contentSha1": "28e355c532ff4ebcb78337593a2ef9890bd4af7e",
      "contentType": "application/octet-stream",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f1162979affbeac79_d20180914_m210813_c002_v0001107_t0011",
      "fileInfo": {
        "src_last_modified_millis": "1532626031627"
      },
      "fileName": "logscript.py",
      "uploadTimestamp": 1536959293000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 7,
      "contentSha1": "dc724af18fbdd4e59189f5fe768a5f8311527050",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10904e5ca06493a1_d20180914_m223119_c002_v0001094_t0002",
      "fileInfo": {
        "src_last_modified_millis": "1536964184056"
      },
      "fileName": "testing.txt",
      "uploadTimestamp": 1536964279000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 8,
      "contentSha1": "596b29ec9afea9e461a20610d150939b9c399d93",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10076875fe98d4af_d20180914_m223128_c002_v0001108_t0050",
      "fileInfo": {
        "src_last_modified_millis": "1536964200750"
      },
      "fileName": "testing2.txt",
      "uploadTimestamp": 1536964288000
    }
  ],
  "nextFileId": null,
  "nextFileName": null
}

Code

import Foundation

let apiUrl = "" // Provided by b2_authorize_account
let accountAuthorizationToken = "" // Provided by b2_authorize_account
let bucketId = "" // The ID of the bucket you are querying

// Create the request
var request = URLRequest(url: URL(string: "\(apiUrl)/b2api/v2/b2_list_file_versions")!)
request.httpMethod = "POST"
request.addValue(accountAuthorizationToken, forHTTPHeaderField: "Authorization")
request.httpBody = "{\"bucketId\":\"\(bucketId)\"}".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!)")
	}
}
task.resume()

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

Output

{
  "files": [
    {
      "accountId": "ACCOUNT_ID",
      "action": "hide",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 0,
      "contentSha1": null,
      "contentType": null,
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10305b68895d22f4_d20180914_m221207_c002_v0001108_t0029",
      "fileInfo": {},
      "fileName": "logscript.py",
      "uploadTimestamp": 1536963127000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 5060,
      "contentSha1": "28e355c532ff4ebcb78337593a2ef9890bd4af7e",
      "contentType": "application/octet-stream",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f1162979affbeac79_d20180914_m210813_c002_v0001107_t0011",
      "fileInfo": {
        "src_last_modified_millis": "1532626031627"
      },
      "fileName": "logscript.py",
      "uploadTimestamp": 1536959293000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 7,
      "contentSha1": "dc724af18fbdd4e59189f5fe768a5f8311527050",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10904e5ca06493a1_d20180914_m223119_c002_v0001094_t0002",
      "fileInfo": {
        "src_last_modified_millis": "1536964184056"
      },
      "fileName": "testing.txt",
      "uploadTimestamp": 1536964279000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 8,
      "contentSha1": "596b29ec9afea9e461a20610d150939b9c399d93",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10076875fe98d4af_d20180914_m223128_c002_v0001108_t0050",
      "fileInfo": {
        "src_last_modified_millis": "1536964200750"
      },
      "fileName": "testing2.txt",
      "uploadTimestamp": 1536964288000
    }
  ],
  "nextFileId": null,
  "nextFileName": null
}

Code

require 'json'
require 'net/http'

api_url = "" # Provided by b2_authorize_account
account_authorization_token = "" # Provided by b2_authorize_account
bucket_id = "" # The ID of the bucket you are querying
uri = URI("#{api_url}/b2api/v2/b2_list_file_versions")
req = Net::HTTP::Post.new(uri)
req.add_field("Authorization","#{account_authorization_token}")
req.body = "{\"bucketId\":\"#{bucket_id}\"}"
http = Net::HTTP.new(req.uri.host, req.uri.port)
http.use_ssl = (req.uri.scheme == 'https')
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

{
  "files": [
    {
      "accountId": "ACCOUNT_ID",
      "action": "hide",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 0,
      "contentSha1": null,
      "contentType": null,
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10305b68895d22f4_d20180914_m221207_c002_v0001108_t0029",
      "fileInfo": {},
      "fileName": "logscript.py",
      "uploadTimestamp": 1536963127000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 5060,
      "contentSha1": "28e355c532ff4ebcb78337593a2ef9890bd4af7e",
      "contentType": "application/octet-stream",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f1162979affbeac79_d20180914_m210813_c002_v0001107_t0011",
      "fileInfo": {
        "src_last_modified_millis": "1532626031627"
      },
      "fileName": "logscript.py",
      "uploadTimestamp": 1536959293000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 7,
      "contentSha1": "dc724af18fbdd4e59189f5fe768a5f8311527050",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10904e5ca06493a1_d20180914_m223119_c002_v0001094_t0002",
      "fileInfo": {
        "src_last_modified_millis": "1536964184056"
      },
      "fileName": "testing.txt",
      "uploadTimestamp": 1536964279000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 8,
      "contentSha1": "596b29ec9afea9e461a20610d150939b9c399d93",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10076875fe98d4af_d20180914_m223128_c002_v0001108_t0050",
      "fileInfo": {
        "src_last_modified_millis": "1536964200750"
      },
      "fileName": "testing2.txt",
      "uploadTimestamp": 1536964288000
    }
  ],
  "nextFileId": null,
  "nextFileName": null
}

Code

String apiUrl = "API_URL"; //Provided by b2_authorize_account 
String accountAuthorizationToken = "ACCOUNT_AUTHORIZATION_TOKEN"; //Provided by b2_authorize_account
String bucketId = "BUCKET_ID; //The unique bucket ID
HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(apiUrl + "/b2api/v2/b2_list_file_versions");
string body = "{\"bucketId\":\"" + bucketId + "\"}";
var data = Encoding.UTF8.GetBytes(body);
webRequest.Method = "POST";
webRequest.Headers.Add("Authorization", accountAuthorizationToken);
webRequest.ContentType = "application/json; charset=utf-8";
webRequest.ContentLength = data.Length;
using (var stream = webRequest.GetRequestStream())
{
stream.Write(data, 0, data.Length);
stream.Close();
}
WebResponse response = (HttpWebResponse)webRequest.GetResponse();
var responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();
response.Close();
Console.WriteLine(responseString);

Output

{
  "files": [
    {
      "accountId": "ACCOUNT_ID",
      "action": "hide",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 0,
      "contentSha1": null,
      "contentType": null,
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10305b68895d22f4_d20180914_m221207_c002_v0001108_t0029",
      "fileInfo": {},
      "fileName": "logscript.py",
      "uploadTimestamp": 1536963127000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 5060,
      "contentSha1": "28e355c532ff4ebcb78337593a2ef9890bd4af7e",
      "contentType": "application/octet-stream",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f1162979affbeac79_d20180914_m210813_c002_v0001107_t0011",
      "fileInfo": {
        "src_last_modified_millis": "1532626031627"
      },
      "fileName": "logscript.py",
      "uploadTimestamp": 1536959293000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 7,
      "contentSha1": "dc724af18fbdd4e59189f5fe768a5f8311527050",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10904e5ca06493a1_d20180914_m223119_c002_v0001094_t0002",
      "fileInfo": {
        "src_last_modified_millis": "1536964184056"
      },
      "fileName": "testing.txt",
      "uploadTimestamp": 1536964279000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 8,
      "contentSha1": "596b29ec9afea9e461a20610d150939b9c399d93",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10076875fe98d4af_d20180914_m223128_c002_v0001108_t0050",
      "fileInfo": {
        "src_last_modified_millis": "1536964200750"
      },
      "fileName": "testing2.txt",
      "uploadTimestamp": 1536964288000
    }
  ],
  "nextFileId": null,
  "nextFileName": null
}

Code

$api_url = ""; // From b2_authorize_account call
$auth_token = ""; // From b2_authorize_account call
$bucket_id = "";  // The ID of the bucket

$session = curl_init($api_url .  "/b2api/v2/b2_list_file_versions");

// Add post fields
$data = array("bucketId" => $bucket_id);
$post_fields = json_encode($data);
curl_setopt($session, CURLOPT_POSTFIELDS, $post_fields); 

// Add headers
$headers = array();
$headers[] = "Authorization: " . $auth_token;
curl_setopt($session, CURLOPT_HTTPHEADER, $headers); 

curl_setopt($session, CURLOPT_POST, true); // HTTP POST
curl_setopt($session, CURLOPT_RETURNTRANSFER, true);  // Receive server response
$server_output = curl_exec($session); // Let's do this!
curl_close ($session); // Clean up
echo ($server_output); // Tell me about the rabbits, George!

Output

{
  "files": [
    {
      "accountId": "ACCOUNT_ID",
      "action": "hide",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 0,
      "contentSha1": null,
      "contentType": null,
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10305b68895d22f4_d20180914_m221207_c002_v0001108_t0029",
      "fileInfo": {},
      "fileName": "logscript.py",
      "uploadTimestamp": 1536963127000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 5060,
      "contentSha1": "28e355c532ff4ebcb78337593a2ef9890bd4af7e",
      "contentType": "application/octet-stream",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f1162979affbeac79_d20180914_m210813_c002_v0001107_t0011",
      "fileInfo": {
        "src_last_modified_millis": "1532626031627"
      },
      "fileName": "logscript.py",
      "uploadTimestamp": 1536959293000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 7,
      "contentSha1": "dc724af18fbdd4e59189f5fe768a5f8311527050",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10904e5ca06493a1_d20180914_m223119_c002_v0001094_t0002",
      "fileInfo": {
        "src_last_modified_millis": "1536964184056"
      },
      "fileName": "testing.txt",
      "uploadTimestamp": 1536964279000
    },
    {
      "accountId": "ACCOUNT_ID",
      "action": "upload",
      "bucketId": "b2f6f21365e1d29f6c580f18",
      "contentLength": 8,
      "contentSha1": "596b29ec9afea9e461a20610d150939b9c399d93",
      "contentType": "text/plain",
      "fileId": "4_zb2f6f21365e1d29f6c580f18_f10076875fe98d4af_d20180914_m223128_c002_v0001108_t0050",
      "fileInfo": {
        "src_last_modified_millis": "1536964200750"
      },
      "fileName": "testing2.txt",
      "uploadTimestamp": 1536964288000
    }
  ],
  "nextFileId": null,
  "nextFileName": null
}