backend

Backend

Kubetail backend server

Overview

The kubetail backend server is a Go-based HTTP server that's designed to proxy requests from the kubetail frontend website to the user's Kubernetes API as well as provide some other custom functionality such as authentication. It uses the Gin Web framework to serve HTTP requests and the Kubernetes Go-client under the hood to communicate with the Kubernetes API. Externally, it responds to Kubernetes-related queries via a GraphQL endpoint powered by gqlgen and serves other requests via a simple REST API.

In development, the backend and frontend servers are kept separate but in production the frontend website is packaged as a static site and deployed to the server's website directory from where it is served at the apex endpoint.

Quickstart

By default, the backend development server will use your local kubectl config file to connect to your Kubernetes API. To run the app in development you can use the go run command:

go run ./cmd/server -c hack/server.yaml

To check on the health status go to: http://localhost:4000/healthz

To use the GraphQL playground go to: http://localhost:4000/graphiql

Configure

CLI Flags

The server executable supports the following command line configuration options:

Flag	Datatype	Description	Default
-c, --config	string	Path to config file	""
-a, --addr	string	Host address to bind to	":4000"
--gin-mode	string	Gin mode (release, debug)	"release"

Config Params

The server can be configured using a configuration file written in YAML, JSON, TOML, HCL or envfile format. It will automatically replace ENV variables written in the format ${NAME} with their corresponding values. The config file supports the following options:

Name	Datatype	Description	Default
addr	string	Host address to bind to	":4000"
auth-mode	string	Auth mode (token, cluster, local)	"token"
gin-mode	string	Gin mode (release, debug)	"release"
kube-config	string	Kubectl config file path	"${HOME}/.kube/config"
csrf.enabled	bool	Enable CSRF protection	true
csrf.field-name	string	CSRF token name in forms	"csrf_token"
csrf.secret	string	CSRF hash key	""
csrf.cookie.name	string	CSRF cookie name	"csrf"
csrf.cookie.path	string	CSRF cookie path	"/"
csrf.cookie.domain	string	CSRF cookie domain	""
csrf.cookie.max-age	int	CSRF cookie max age (in seconds)	43200
csrf.cookie.secure	bool	CSRF cookie secure property	false
csrf.cookie.http-only	bool	CSRF cookie HttpOnly property	true
csrf.cookie.same-site	string	CSRF cookie SameSite property (strict, lax, none)	"strict"
logging.enabled	bool	Enable logging	true
logging.level	string	Log level	"info"
logging.format	string	Log format (json, pretty)	"json"
logging.access-log.enabled	bool	Enable access log	true
logging.access-log.hide-health-checks	bool	Hide requests to /healthz	false
session.secret	string	Session hash key	""
session.cookie.path	string	Session cookie path	"/"
session.cookie.domain	string	Session cookie domain	""
session.cookie.max-age	int	Session cookie max age (in seconds)	43200
session.cookie.secure	bool	Session cookie secure property	false
session.cookie.http-only	bool	Session cookie HttpOnly property	true
session.cookie.same-site	string	Session cookie SameSite property (strict, lax, none)	"strict"

GraphQL

The GraphQL schema can be found here: GraphQL schema. To run the gqlgen GraphQL code generator use the go generate command:

go generate ./...

Test

This project uses the stretchr/testify library for testing. To run the test suite:

go test ./...