Lithium/main.go

package main

import (
	"encoding/json"
	"net/http"

	"github.com/geplauder/lithium/middlewares"
	"github.com/geplauder/lithium/pipelines"
	"github.com/geplauder/lithium/settings"
	"github.com/geplauder/lithium/storage"
	"github.com/gorilla/mux"
	"github.com/spf13/afero"
)

const Name string = "Lithium"
const Version string = "0.1.0"

var GitCommit string

type Metadata struct {
	Name       string `json:"name"`
	Version    string `json:"version"`
	CommitHash string `json:"commit_hash"`
}

func PipelineHandler(pipeline pipelines.IPipeline, storageProvider storage.IStorageProvider, w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/json")
	err := json.NewEncoder(w).Encode(pipeline)
	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
	}
}

func IndexHandler(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/json")
	err := json.NewEncoder(w).Encode(Metadata{Name, Version, GitCommit})
	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
	}
}

func RegisterPipelineRoutes(r *mux.Router, pipelines []pipelines.IPipeline, storageProvider storage.IStorageProvider) {
	for _, pipeline := range pipelines {
		r.HandleFunc("/"+pipeline.GetSlug(), func(w http.ResponseWriter, r *http.Request) {
			PipelineHandler(pipeline, storageProvider, w, r)
		})
	}
}

func main() {
	appSettings, err := settings.LoadSettings(afero.NewOsFs())
	if err != nil {
		panic(err)
	}

	var storageProvider storage.IStorageProvider

	if appSettings.StorageProvider.Type == 0 {
		storageProvider = storage.GetFileSystemStorageProvider(appSettings.StorageProvider.BasePath, "")
	} else {
		panic("Invalid file system provided!")
	}

	pipes := pipelines.LoadPipelines()

	r := mux.NewRouter()

	if appSettings.Authentication.Enabled {
		authMiddleware := middlewares.CreateAuthenticationMiddleware(appSettings.Authentication.Token)

		r.Use(authMiddleware.Middleware)
	}

	if appSettings.RateLimiter.Enabled {
		rateLimiterMiddleware, err := middlewares.CreateRateLimiterMiddleware(appSettings.RateLimiter.RequestsPerMinute, appSettings.RateLimiter.AllowedBurst)
		if err != nil {
			panic(err)
		}

		r.Use(rateLimiterMiddleware.Middleware)
	}

	r.HandleFunc("/", IndexHandler)

	RegisterPipelineRoutes(r, pipes, storageProvider)

	err = http.ListenAndServe(appSettings.Endpoint, r)
	if err != nil {
		panic(err)
	}
}