/slackdump

A command line utility to create and save an archive of slack public and private messages and threads, files, and users.

Primary LanguageGoGNU General Public License v3.0GPL-3.0

Slack Dumper

Buy me a cup of tea

Join the discussion

Read the set up guide on Medium.com

Purpose: dump Slack messages, users and files using browser token and cookie.

Typical use scenarios:

  • archive your private conversations from Slack when the administrator does not allow you to install applications OR you don't want to use potentially privacy-violating third-party tools,
  • archive channels from Slack when you're on a free "no archive" subscription, so you don't lose valuable knowledge in those channels.

The library is "fit-for-purpose" quality and provided AS-IS. I can't say it's ready for production, as it lacks most of the unit tests, but will do for ad-hoc use.

Slackdump accepts two types of input: # the URL/link of the channel or thread, OR # the ID of the channel.

Contents

Usage

  1. Download the archive from the Releases page for your operating system. (NOTE: MacOS users should download darwin release file).
  2. Unpack
  3. Change directory to where you have unpacked the archive.
  4. Run ./slackdump -h to see help.

How to authenticate

Getting the authentication data

  1. Open up your Slack in browser and login.
TOKEN
  1. Open your browser's Developer Console.
  2. Go to the Network tab
  3. In the toolbar, switch to Fetch/XHR view.
  4. Open any channel or private conversation in Slack. You'll see a bunch of stuff appearing in Network panel.
  5. In the list of requests, find the one starting with channels.prefs.get?, click it and click on Headers tab in the opened pane.
  6. Scroll down, until you see Form Data
  7. Grab the token: value (it starts with xoxc-), by right clicking the value and choosing "Copy Value".

If you don't see the token value in Google Chrome - switch to Payload tab, your token is waiting for you there.

COOKIE
  1. Switch to Application tab and select Cookies in the left navigation pane.
  2. Find the cookie with the name "d". That's right, just the letter "d".
  3. Double-click the Value of this cookie.
  4. Press Ctrl+C or Cmd+C to copy it's value to clipboard.
  5. Save it for later.

Setting up the application

  1. Create the file named .env next to where the slackdump executable in any text editor. Alternatively the file can be named secrets.txt or .env.txt.

  2. Add the token and cookie values to it. End result should look like this:

    SLACK_TOKEN=xoxc-<...elided...>
COOKIE=12345472908twp<...elided...>

  3. Save the file and close the editor.

Dumping conversations

As it was already mentioned in the introduction, Slackdump supports two ways of providing the conversation IDs that you want to save:

  • By ID: it expects to see Conversation IDs.
  • By URL: it expects to see URLs. You can get URL by choosing "Copy Link" in the Slack on the channel or thread.

IDs or URLs can be passed on the command line or read from a file (using the -i command line flag), in that file, every ID or URL should be placed on a separate line. Slackdump can automatically detect if it's an ID or a URL.

Providing the list on the command line

Firstly, dump the channel list to choose what you want to dump:

slackdump -c

You will get the output resembling the following:

2021/10/31 17:32:34 initializing...
2021/10/31 17:32:35 retrieving data...
2021/10/31 17:32:35 done
ID           Arch  Saved  What
CHXXXXXXX    -     -      #everything
CHXXXXXXX    -     -      #everyone
CHXXXXXXX    -     -      #random
DHMAXXXXX    -     -      @slackbot
DNF3XXXXX    -     -      @alice
DLY4XXXXX    -     -      @bob

You'll need the value in the ID column.

To dump the channel, run the following command:

slackdump <ID1> [ID2] ... [IDn]

By default, slackdump generates a json file with the convesation. If you want the convesation to be saved to a text file as well, use the -r text command line parameter. See example below.

Example

You want to dump conversations with @alice and @bob to text files and save all the files (attachments) that you all shared in those conversations:

slackdump -r text -f DNF3XXXXX DLY4XXXXX https://....
          ━━━┯━━━ ━┯ ━━━┯━━━━━ ━━━┯━━━━━ ━━━━┯━━━━━┅┅
             │     │    │         │          │
             │     │    │         ╰─: @alice │
             │     │    ╰───────────: @bob   ┊
             │     ╰────────────────: save files
             ╰──────────────────────: text file output
         thread or conversation URL :────────╯

Conversation URL:

To get the conversation URL link, use this simple trick that they won't teach you at school:

  1. In Slack, right click on the conversation you want to dump (in the channel navigation pane on the left)
  2. Choose "Copy link".

Thread URL:

  1. In Slack, open the thread that you want to dump.
  2. The thread opens to the right of the main conversation window
  3. On the first message of the thread, click on three vertical dots menu (not sure how it's properly called), choose "Copy link"

Run the slackdump and provide the URL link as an input:

slackdump -f  https://xxxxxx.slack.com/archives/CHM82GX00/p1577694990000400
          ━┯  ━━━━━━┯━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
           │        ╰─────: URL of the thread
           ╰──────────────: save files

Reading data from the file

Slackdump can read the list of the channels and URLs to dump from the file.

  1. Create the file that will contain all the necessary IDs and/or URLs, I'll use "links.txt" in the example.

  2. Copy/paste all the IDs and URLs into that file, one per line.

  3. Run slackdump with "-i" command line flag. "-i" stands for "input":

    slackdump -i links.txt
          ━━━━┯━━━━━━━
              │
              ╰───────: instructs slackdump to use the file input

Dumping users

To view all users, run:

slackdump -u

By default, slackdump exports users in text format. If you need to output json, use -r json flag.

Dumping channels

To view channels, that are visible to your account, including group conversations, archived chats and public channels, run:

slackdump -c

By default, slackdump exports users in text format. If you need to output json, use -r json flag.

Command line flags reference

In this section there will be some explanation provided for the possible command line flags.

This doc may be out of date, to get the current command line flags with a brief description, run:

slackdump -h

Command line flags are described as of version v1.3.1.

-V
print version and exit
-c
same as -list-channels
-cookie
along with -t sets the authentication values. Can also be set using COOKIE environment variable. Must contain the value of d= cookie.
-cpr
number of conversation items per request. (default 200). This is the amount of individual messages that will be fetched from Slack API per single API request.
-dl-retries number
rate limit retries for file downloads. (default 3). If the file download process hits the Slack Rate Limit reponse (HTTP ERROR 429), slackdump will retry the download this number of times, for each file.
-download
enable files download. If this flag is specified, slackdump will download all attachments, including the ones in threads.
-download-workers
number of file download worker threads. (default 4). File download is performed with multiple goroutines. This is the number of goroutines that will be downloading files. You generally wouldn't need to modify this value.
-dump-from
timestamp of the oldest message to fetch from (i.e. 2020-12-31T23:59:59). Allows setting the lower boundary of the timeframe for conversation dump. This is useful when you don't need everything from the beginning of times.
-dump-to
timestamp of the latest message to fetch to (i.e. 2020-12-31T23:59:59). Same as above, but for upper boundary.
-f
shorthand for -download (means "files")
-ft

output file naming template. This parameter allows to define custom naming for output conversation files.

It uses Go templating system. Available template tags:

{{.ID}}:channel ID
{{.Name}}:channel Name
{{.ThreadTS}}:thread timestamp. This tag can not be used on it's own, it must be combined with at least one of the above tags.

You can use any of the standard template functions. The default value for this parameter outputs the channelID as the filename. For threads, it will use channelID-threadTS.

Below are some of the common templates you could use.

Channel ID and thread:
{{.ID}}{{if .ThreadTS}}-{{.ThreadTS}}{{end}}

The output file will look like "C480129421.json" for a channel if channel has ID=C480129421 and "C4840129421-1234567890.123456.json" for a thread. This is the default template.
Channel Name and thread:
{{.Name}}{{if .ThreadTS}}({{.ThreadTS}}){{end}}

The output file will look like "general.json" for the channel and "general(123457890.123456).json" for a thread.
-i
specify the input file with Channel IDs or URLs to be used instead of giving the list on the command line, one per line. Use "-" to read input from STDIN. Example: -i my_links.txt.
-limiter-boost
same as -t3-boost. (default 120)
-limiter-burst
same as -t3-burst. (default 1)
-list-channels
list channels (aka conversations) and their IDs for export. The default output format is "text". Use -r json to output as JSON.
-list-users
list users and their IDs. The default output format is "text". Use -r json to output as JSON.
-no-user-cache
skip fetching users. If this flag is specified, users won't be fetched during startup. This disables the username resolving for the text output, I don't know why someone would use this flag, but it's there if you must.
-npr
chaNnels per request. The amount of channels that will be fetched per API request when listing channels. Setting it to higher value than 100 bears no tangible outcome - Slack never returns more than 100 channels per request. Greedy.
-o
output filename for users and channels. Use '-' for standard output. (default "-")
-r
report (output) format. One of 'json' or 'text'. For channels and users - will output only in the specified format. For messages - if 'text' is requested, the text file will be generated along with json.
-t
Specify slack API token, (environment: SLACK_TOKEN). This should be used along with --cookie flag.
-t2-boost
Tier-2 limiter boost in events per minute (affects users and channels APIs).
-t2-burst
Tier-2 limiter burst in events (affects users and channels APIs). (default 1)
-t2-retries
rate limit retries for channel listing. (affects users and channels APIs). (default 20)
-t3-boost
Tier-3 rate limiter boost in events per minute, will be added to the base slack tier event per minute value. Affects conversation APIs. (default 120)
-t3-burst
allow up to N burst events per second. Default value is safe. Affects conversation APIs (default 1)
-t3-retries
rate limit retries for conversation. Affects conversation APIs. (default 3)
-trace filename
allows to specify the trace filename and enable tracing (optional). Use this flag if requested by developer. The trace file does not contain any sensitive or PII.
-u
shorthand for -list-users.
-user-cache-age
user cache lifetime duration. Set this to 0 to disable cache. (default 4h0m0s) User cache is used to speedup consequent runs of slackdump. Known issue - if you're changing slack workspace, make sure to delete the cache file, or set this to 0.
-user-cache-file
user cache filename. (default "users.json") See note for -user-cache-age above.
-v
verbose messages

As a library

Download:

go get github.com/rusq/slackdump

Use:

import "github.com/rusq/slackdump"

func main() {
  sd, err := slackdump.New(os.Getenv("TOKEN"), os.Getenv("COOKIE"))
  if err != nil {
      // handle
  }
  // ... read the docs
}

FAQ

Q:Do I need to create a Slack application?
A:No, you don't. You need to grab that token and cookie from the browser Slack session. See Usage at the top of the file.
Q:I'm getting "invalid_auth" error
A:Go get the new Cookie from the browser and Token as well.

Bulletin Board

Messages that were conveyed with the donations:

  • 25/01/2022: Stay away from TheSignChef.com, ya hear, they don't pay what they owe to their employees.