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+# Slack Dumper
+
+Purpose:  archive your private and public Slack messages, users, channels,
+files and emojis.  Generate Slack Export without admin privileges.
+
+[![Slackdump screenshot](doc/slackdump.webp)](https://github.com/rusq/slackdump/releases/)
+
+**Quick links**:
+
+- [Join the discussion in Telegram](https://t.me/slackdump).
+- [Buy me a cup of tea](https://ko-fi.com/rusq_), or use **Github Sponsors**
+  button on the top of the page.
+- [![Go reference](https://pkg.go.dev/badge/github.com/rusq/slackdump/v3.svg)][godoc]
+- How to's:
+
+  - [Mattermost migration][mmost] steps
+  - [SlackLogViewerとSlackdumpを一緒に使用する](https://kenkyu-note.hatenablog.com/entry/2022/09/02/090949)
+  - [v1 Overview on Medium.com](https://medium.com/@gilyazov/downloading-your-private-slack-conversations-52e50428b3c2)  (outdated)
+
+[godoc]: https://pkg.go.dev/github.com/rusq/slackdump/v3/
+[mmost]: doc/usage-export.rst
+
+## Description
+
+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,
+* create a Slack Export archive without admin access, or
+* save your favourite emojis.
+
+There are four modes of operation (more on this in [User Guide][ug]):
+
+1. List users/channels
+1. Dumping messages and threads
+1. Creating a Slack Export in Mattermost or Standard modes.
+1. Emoji download mode.
+
+Slackdump accepts two types of input (see `Dumping Conversations`_ section):
+
+1. the URL/link of the channel or thread, OR
+1. the ID of the channel.
+
+[ug]: doc/README.rst
+
+Quick Start
+===========
+
+On macOS, you can install Slackdump with Homebrew::
+
+```shell
+brew install slackdump
+```
+
+On other Operating Systems, please follow these steps:
+
+1. Download the latest release for your operating system from the [releases] page.
+1. Unpack the archive to any directory.
+1. Run the `./slackdump` or `slackdump.exe` executable (see note below).
+1. You know the drill:  use arrow keys to select the menu item, and Enter (or
+   Return) to confirm.
+
+[releases]: https://github.com/rusq/slackdump/releases/
+
+By default, Slackdump uses the EZ-Login 3000 automatic login, and interactive
+mode.
+
+.. NOTE::
+  On Windows and macOS you may be presented with "Unknown developer" window,
+  this is fine.  Reason for this is that the executable hasn't been signed by
+  the developer certificate.
+
+  To work around this:
+
+  - **on Windows**: click "more information", and press "Run
+    Anyway" button.
+  - **on macOS**: open the folder in Finder, hold Option and double click the
+    executable, choose Run.
+
+
+## Slackord2: Migrating to Discord
+
+If you're migrating to Discord, the recommended way is to use
+[Slackord2](https://github.com/thomasloupe/Slackord2) — a great tool with a
+nice GUI, that is compatible with the export files generated by Slackdump.
+
+## User Guide
+
+For more advanced features and instructions, please see the [User Guide][ug].
+
+# Previewing Results
+
+Once the workspace data is dumped, you can run built-in viewer:
+
+```shell
+slackdump view <zip or directory>
+```
+
+The built-in viewer supports all types of dumps:
+
+1. Slackdump Archive format;
+1. Standard and Mattermost Slack Export;
+1. Dump mode files
+
+The built-in viewer is experimental, any contributions to make it better looking are welcome.
+
+Alternatively, you can use one of the following tools to preview the
+export results:
+
+- [SlackLogViewer] - a fast and powerful Slack Export viewer written in C++, works on Export files (images won't be displayed, unless you used an export token flag).
+- [Slackdump2Html] - a great Python application that converts Slack Dump to a
+  static browsable HTML.  It works on Dump mode files.
+- [slack export viewer][slack-export-viewer] - Slack Export Viewer is a well known viewer for
+  slack export files.
+
+[SlackLogViewer]: https://github.com/thayakawa-gh/SlackLogViewer/releases
+[Slackdump2Html]: https://github.com/kununu/slackdump2html
+[slack-export-viewer]: https://github.com/hfaran/slack-export-viewer
+
+
+## Using as a library
+
+Download:
+
+```shell
+go get github.com/rusq/slackdump/v3
+```
+
+
+### Example
+
+```go
+package main
+
+import (
+  "context"
+  "log"
+
+  "github.com/rusq/slackdump/v2"
+  "github.com/rusq/slackdump/v2/auth"
+)
+
+func main() {
+  provider, err := auth.NewValueAuth("xoxc-...", "xoxd-...")
+  if err != nil {
+      log.Print(err)
+      return
+  }
+  sd, err := slackdump.New(context.Background(), provider)
+  if err != nil {
+      log.Print(err)
+      return
+  }
+  _ = sd
+}
+```
+
+See [Package Documentation][godoc].
+
+### Using Custom Logger
+Slackdump uses a simple [rusq/dlog][dlog] as a default logger (it is a wrapper around
+the standard logger that adds `Debug*` functions).
+
+If you want to use the same default logger that Slackdump uses in your
+application, it is available as `logger.Default`.
+
+No doubts that everyone has their own favourite logger that is better than other
+miserable loggers.  Please read below for instructions on plugging your
+favourite logger.
+
+[dlog]: https://github.com/rusq/dlog
+
+#### Logrus
+Good news is [logrus] can be plugged in straight away, as it implements the
+`logger.Interface` out of the box.
+
+```go
+  lg := logrus.New()
+  sd, err := slackdump.New(context.Background(), provider, WithLogger(lg))
+  if err != nil {
+      log.Print(err)
+      return
+  }
+```
+
+[logrus]: https://github.com/sirupsen/logrus
+
+
+#### Glog and others
+If you need to use some other logger, such as [glog], it is a matter of wrapping
+the calls to satisfy the `logger.Interface` (defined in the [logger]
+package), and then setting the `Logger` variable in `slackdump.Options` (see
+[options.go]), or using `WithLogger` option.
+
+[glog]:https://github.com/golang/glog
+[logger]: logger/logger.go
+[options.go]: options.go
+
+## FAQ
+
+#### Do I need to create a Slack application?
+
+No, you don't.  Just run the application and EZ-Login 3000 will take
+care of the authentication or, alternatively, grab that token and
+cookie from the browser Slack session.  See `User Guide`_.
+
+#### I'm getting "invalid_auth" error
+
+Go get the new Cookie from the browser and Token as well.
+
+#### Slackdump takes a very long time to cache users
+
+Disable the user cache with `-no-user-cache` flag.
+
+#### How to read the export file?
+
+```shell
+slackdump view <ZIP-archive or directory>
+```
+
+#### My Slack Workspace is on the Free plan.  Can I get data older than 90-days?
+
+No, unfortunately you can't.  Slack doesn't allow to export data older than 90
+days for free workspaces, the API does not return any data before 90 days for
+workspaces on the Free plan.
+
+## Thank you
+Big thanks to all contributors, who submitted a pull request, reported a bug,
+suggested a feature, helped to reproduce, or spent time chatting with me on
+the Telegram or Slack to help to understand the issue and tested the proposed
+solution.
+
+Also, I'd like to thank all those who made a donation to support the project:
+
+- Vivek R.
+- Fabian I.
+- Ori P.
+- Shir B. L.
+- Emin G.
+- Robert Z.
+- Sudhanshu J.
+
+# Bulletin Board
+
+Messages that were conveyed with the donations:
+
+- 25/01/2022: Stay away from [TheSignChef.com][glassdoor], ya hear, they don't
+  pay what they owe to their employees.
+
+[glassdoor]: https://www.glassdoor.com/Reviews/The-Sign-Chef-Reviews-E1026706.htm