Advanced usage

Environment variables

Several environment variables can be passed to Gokapi. They can be used to modify settings that are not present during setup or to pass cloud storage credentials without saving them to the filesystem.

Passing environment variables to Gokapi

Docker

Pass the variable with the -e argument. Example for setting the port in use to 12345 and the database filename to database.sqlite:

docker run -it -e GOKAPI_PORT=12345 -e GOKAPI_DB_NAME=database.sqlite f0rc3/gokapi:latest

Bare Metal

Linux / Unix

For Linux / Unix environments, execute the binary in this format:

GOKAPI_PORT=12345 GOKAPI_DB_NAME=database.sqlite [...] ./Gokapi

Windows

For Windows environments, you need to run setx first, e.g.:

setx GOKAPI_PORT 12345
setx GOKAPI_DB_NAME database.sqlite
[...]
Gokapi.exe

Available environment variables

Name	Action	Persistent [*]	Default
GOKAPI_CONFIG_DIR	Sets the directory for the config file	No	config
GOKAPI_CONFIG_FILE	Sets the name of the config file	No	config.json
GOKAPI_DATA_DIR	Sets the directory for the data	Yes	data
GOKAPI_DB_NAME	Sets the name for the database file	No	gokapi.sqlite
GOKAPI_LENGTH_ID	Sets the length of the download IDs. Value needs to be 5 or more	Yes	15
GOKAPI_MAX_FILESIZE	Sets the maximum allowed file size in MB	Yes	102400 (100GB)
GOKAPI_MAX_MEMORY_UPLOAD	Sets the amount of RAM in MB that can be allocated for an upload. Any upload with a size greater than that will be written to a temporary file	Yes	20
GOKAPI_PORT	Sets the webserver port	Yes	53842
GOKAPI_DISABLE_CORS_CHECK	Disables the CORS check on startup and during setup, if set to “true”	No	false
GOKAPI_LOG_STDOUT	Also outputs all log file entries to the console output	No	false
TMPDIR	Sets the path which contains temporary files	No	Non-Docker: Default OS path Docker: [DATA_DIR]

[*]

Variables that are persistent must be submitted during the first start when Gokapi creates a new config file. They can be omitted afterwards. Non-persistent variables need to be set on every start.

All values that are described in Cloudstorage can be passed as environment variables as well. No values are persistent; therefore, they need to be set on every start.

Name	Action	Example
GOKAPI_AWS_BUCKET	Sets the bucket name	gokapi
GOKAPI_AWS_REGION	Sets the region name	eu-central-000
GOKAPI_AWS_KEY	Sets the API key	123456789
GOKAPI_AWS_KEY_SECRET	Sets the API key secret	abcdefg123
GOKAPI_AWS_ENDPOINT	Sets the endpoint	eu-central-000.provider.com
GOKAPI_AWS_PROXY_DOWNLOAD	If true, users will not be redirected to a pre-signed S3 URL for downloading. Instead, Gokapi will download the file and proxy it to the user	true (default:false)

API

Gokapi offers an API that can be reached at http(s)://your.gokapi.url/api/. You can find the current documentation with an overview of all API functions and examples at http(s)://your.gokapi.url/apidocumentation/.

Interacting with the API

All API calls will need an API key as authentication or a valid admin session cookie. An API key can be generated in the web UI in the menu “API”. The API key needs to be passed as a header.

Example: Getting a list of all stored files with curl

curl -X GET "https://your.gokapi.url/api/files/list" -H "accept: application/json" -H "apikey: secret"

Some calls expect parameters as form/post parameter, others as headers. Please refer to the current API documentation.

Example: Uploading a file

curl -X POST "https://your.gokapi.url/api/files/add" -H "accept: application/json" -H "apikey: secret" -H "Content-Type: multipart/form-data" -F "allowedDownloads=1" -F "expiryDays=5" -F "password=" -F "file=@yourfile.dat"

Example: Deleting a file

curl -X DELETE "https://your.gokapi.url/api/files/delete" -H "accept: */*" -H "id: PFnh2DlQRS2PVKM" -H "apikey: secret"

Automatic Deployment

It is possible to deploy Gokapi without having to run the setup. You will need to complete the setup on a temporary instance first. This is to create the configuration files, which can then be used for deployment.

Configuration Files

The configuration consists of up to two files in the configuration directory (default: config). All files can be read-only, however config.json might need write access in some situations.

cloudconfig.yml

Stores the access data for cloud storage. This can be reused without modification, however all fields can also be set with environment variables. The file does not exist if no cloud storage is used and can always be read-only.

config.json

Contains the server configuration. If you want to deploy Gokapi in multiple instances for redundancy (e.g. all instances share the same data), then the configuration file can be reused without modification. Otherwise you need to modify it before deploying (see below). Can be read-only, but might need write access when upgrading Gokapi to a newer version. Needs write access when re-running setup or changing the admin password.

Modifying config.json to deploy without setup

If you want to deploy Gokapi to multiple instances that contain different data, you have to modify the config.json. Open it and change the following fields:

Field	Operation	Example
SaltAdmin	Change to empty value	“SaltAdmin”: “”,
SaltFiles	Change to empty value	“SaltFiles”: “”,
Password	Change to empty value	“Password”: “”,
Username	Change to the username of your preference, if you are using internal username/password authentication	“Username”: “admin”,

Setting an admin password

If you are using internal username/password authentication, run the binary with the parameter --deployment-password [YOUR_PASSWORD]. This sets the password and also generates a new salt for the password. This has to be done before Gokapi is run for the first time on the new instance. Alternatively you can do this on the orchestrating machine and then copy the configuration file to the new instance.

If you are using a Docker image, this has to be done by starting a container with the entrypoint /app/run.sh, for example:

docker run --rm -v gokapi-data:/app/data -v gokapi-config:/app/config  f0rc3/gokapi:latest /app/run.sh --deployment-password newPassword

Customising

By default, all files are included in the executable. If you want to change the layout (e.g. add your company logo or change the app name etc.), follow these steps:

1. Download the source code for the Gokapi version you are using. It is either attached to the specific release on Github or you can clone the repository and checkout the tag for the specific version.

2. Copy either the folder static, templates or both from the internal/webserver/web folder to the directory where the executable is located (if you are using Docker, mount the folders into the the /app/ directory, e.g. /app/templates).

3. Make changes to the folders. static contains images, CSS files and JavaScript. templates contains the HTML code.

4. Restart the server. If the folders exist, the server will use the local files instead of the embedded files.

5. Optional: To embed the files permanently, copy the modified files back to the original folders and recompile with go build Gokapi/cmd/gokapi.