Setup

There are two different ways to setup Gokapi: Either a bare metal approach or docker.

Also there are two different versions: Stable indicates that you are using the latest release which should work without any bugs. Unstable is the latest developer version, which might include more features, but could also contain bugs.

Installation

Bare Metal

Stable version

Download the latest release and copy the executable into a new folder with write permissions. Select the executable according to your system. If you are using Windows, select gokapi-windows_amd64, for Mac either gokapi-darwin_amd64 or gokapi-darwin_arm64 and for Linux the gokapi-linux_ file matching your system.

Unstable version

Only recommended if you have expierence with the command line. Go 1.20+ needs to be installed.

Create a new folder and in this folder execute

git clone https://github.com/Forceu/Gokapi.git .
go generate ./...
go build Gokapi/cmd/gokapi

This will compile the source code and create an executable from the latest code.

Docker

To download, run the following command, and replace YOURTAG with either latest (stable) or latest-dev (unstable).

docker pull f0rc3/gokapi:YOURTAG

Most of the time, you will need the latest tag.

If you don’t want to download the prebuilt image, you can find the Dockerfile on the Github project page.

First Start

After the first start you will be redirected to a setup webpage. To change the port for the setup please set the GOKAPI_PORT env variable, see Environment variables

Starting Gokapi

Bare Metal

To start Gokapi, execute the binary with your command line or by double clicking.

Docker

To start the container, run the following command:

docker run -v gokapi-data:/app/data -v gokapi-config:/app/config -p 127.0.0.1:53842:53842 f0rc3/gokapi:latest

With the argument -p 127.0.0.1:53842:53842 the service will only be accessible from the machine it is running on. In most usecases you will use a reverse proxy for SSL - if you want to make the service available to other computers in the network without a reverse proxy, replace the argument with -p 53842:53842. Please note, unless you select SSL during the setup, the traffic will not be encrypted that way and data like passwords or transferred files can easily be read by third parties!

Initial Setup

During the first start, a new configuration file will be created and you will be asked for several inputs. With your webbrowser open http://localhost:53842/setup (or the appropriate URL) and follow the setup.

Webserver

The following configuration can be set:

  • Bind to localhost Only allow the server to be accessed from the machine it is running on. Select this if you are running Gokapi behind a reverse proxy or for testing purposes

  • Use SSL Generates a self-signed SSL certificate (which can be replaced with a valid one). Select this if you are not running Gokapi behind a reverse proxy. Please note: Gokapi needs to be restarted in order to renew a certificate.

  • Save IP If set, the IP address of the client requesting a download will be saved to the log file. This might not be GDPR compliant.

  • Webserver Port Set the port that Gokapi can be accessed on

  • Public Facing URL Enter the URL where users from an external network can use to reach Gokapi. The URL will be used for generating download links

  • Redirection URL By default Gokapi redirects to this URL instead of showing a generic page if no download link was passed

Authentication

This menu guides you through the authentication setup, where you select how an admin user logs in (only user that can upload files)

Username / Password

The default authentication method. A single admin user will be generated that authenticates with a password

OAuth2 OpenID Connect

Use this to authenticate with an OIDC server, eg. Google, Github or an internal server. Note: If a user is revoked on the OIDC server, it might take several days to affect the Gokapi session.

Option

Expected Entry

Example

Provider URL

The URL to connect to the OIDC server

https://accounts.google.com

Client ID

Client ID provided by the OIDC server

[random String]

Client Secret

Client secret provided by the OIDC server

[random String]

Allowed users

List of users that is allowed to log in as an admin. Separate users with a semicolon or leave blank to allow any authenticated user

gokapiuser@gmail.com;companyadmin@gmail.com

When creating an OIDC client on the server, you will need to provide a redirection URL. Enter http[s]://[gokapi URL]/oauth-callback

You can find a guide on how to create an OIDC client with Github at Setting up GitHub OAuth 2.0 and a guide for Google at Setting up OAuth 2.0.

Header Authentication

Only use this if you are running Gokapi behind a reverse proxy that is capable of authenticating users, e.g. by using Authelia or Authentik.

Enter the key of the header that returns the username. For Authelia this would be Remote-User and for Authentik X-authentik-username. Separate users with a semicolon or leave blank to allow any authenticated user, e.g. gokapiuser@gmail.com;companyadmin@gmail.com

Access Restriction

Only use this if you are running Gokapi behind a reverse proxy that is capable of authenticating users, e.g. by using Authelia or Authentik.

This option disables Gokapis internal authentication completely, except for API calls. The following URLs need to be restricted by the reverse proxy:

  • /admin

  • /apiDelete

  • /apiKeys

  • /apiNew

  • /delete

  • /e2eInfo

  • /e2eSetup

  • /logs

  • /uploadChunk

  • /uploadComplete

  • /uploadStatus

Warning: This option has potential to be very dangerous, only proceed if you know what you are doing!

Storage

Here you can choose where uploaded files shall be stored. Use the option to always store image files to the local storage, if you want to use encryption for cloudstorage, but require hotlink support.

Local Storage

Stores files locally in the subdirectory data by default.

Cloudstorage

Stores files remotely on an S3 compatible server, e.g. Amazon AWS S3 or Backblaze B2. Please note that files will be stored in plain-text, if no encryption is selected later on.

It is highly recommended to create a new bucket for Gokapi and set it to “private”, so that no file can be downloaded externally. For each download request Gokapi will create a public URL that is only valid for a couple of seconds, so that the file can be downloaded from the external server directly instead of routing it through the local server.

You then need to create an app key with read-/write-access to this bucket. If you are planning to use the encryption feature, make sure to set the bucket’s CORS rules to allow access from the Gokapi URL.

The following data needs to be provided:

Key

Description

Required

Example

Bucket

Name of the bucket in use

yes

gokapi

Region

Name of the region

yes

eu-central-1

KeyId

Name of the API key

yes

keyname123456789

KeySecret

Value of the API key secret

yes

verysecret123

Endpoint

Endpoint to use. Leave blank if using AWS S3.

only for Backblaze B2

s3.eu-central-001.backblazeb2.com

Encryption

Warning: Encryption has not been audited.

There are three different encryption levels, level 1 encrypts only local files and level 2 encrypts local and files stored on cloud storage (e.g. AWS S3). Decryption of files on remote storage is done client-side, for which a 2MB library needs to be downloaded on first visit. End-to-End encryption (level 3) encrypts the files client-side, therefore even if the Gokapi server has been compromised, no data should leak to the attacker. If the decryption is done client-side, the dowload on mobile devices may be significantly slower.

There are some drawbacks of using encryption:

No Encryption

Level 1 Local

Level 2 Full

Level 3 End-to-End

File Encryption

None

Only local files

Local and cloud storage

Local and cloud storage

Hotlink Support

Yes

Yes

Only local files

No

Download Progress Indication

Yes

Only cloud storage

No

No

Download Speed

Full

Might be slower for local files

Slower for remote files, might be slower for local files

Slower for all files

You can choose to store the key in the configuration file, which is preferred if access by other parties to your configuration file is unlikely.

If you are concerned that the configuration file can be read, you can also choose to enter a master password on startup. This needs to be entered in the command line however and Gokapi will not be able to start without it.

Please note: If you re-run the setup and enable encryption, unencrypted files will stay unencrypted. If you change any configuration related to encryption, all already encrypted files will be deleted.

Changing Configuration

To change any settings set in the initial setup (e.g. your password or storage location), run Gokapi with the parameter --reconfigure and follow the instructions. A random username and password will be generated and displayed in the programm output to access the configuration webpage, as all entered information can be read in plain text (except the user password).

If you are using Docker, shut down the running instance and create a new temporary container with the follwing command:

docker run --rm -p 127.0.0.1:53842:53842 -v gokapi-data:/app/data -v gokapi-config:/app/config  f0rc3/gokapi:latest /app/gokapi --reconfigure