// Copyright 2019 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy of
// the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.
// Package config implements structures to store Nixery's configuration at
// runtime as well as the logic for instantiating this configuration from the
// environment.
package config
import (
"os"
log "github.com/sirupsen/logrus"
)
func getConfig(key, desc, def string) string {
value := os.Getenv(key)
if value == "" && def == "" {
log.WithFields(log.Fields{
"option": key,
"description": desc,
}).Fatal("missing required configuration envvar")
} else if value == "" {
return def
}
return value
}
// Backend represents the possible storage backend types
type Backend int
const (
GCS = iota
FileSystem
)
// Config holds the Nixery configuration options.
type Config struct {
Port string // Port on which to launch HTTP server
Pkgs PkgSource // Source for Nix package set
Timeout string // Timeout for a single Nix builder (seconds)
WebDir string // Directory with static web assets
PopUrl string // URL to the Nix package popularity count
Backend Backend // Storage backend to use for Nixery
}
func FromEnv() (Config, error) {
pkgs, err := pkgSourceFromEnv()
if err != nil {
return Config{}, err
}
var b Backend
switch os.Getenv("NIXERY_STORAGE_BACKEND") {
case "gcs":
b = GCS
case "filesystem":
b = FileSystem
default:
log.WithField("values", []string{
"gcs",
}).Fatal("NIXERY_STORAGE_BACKEND must be set to a supported value (gcs or filesystem)")
}
return Config{
Port: getConfig("PORT", "HTTP port", ""),
Pkgs: pkgs,
Timeout: getConfig("NIX_TIMEOUT", "Nix builder timeout", "60"),
WebDir: getConfig("WEB_DIR", "Static web file dir", ""),
PopUrl: os.Getenv("NIX_POPULARITY_URL"),
Backend: b,
}, nil
}
