Merge pull request #5 from promhippie/multi-credentials

Add support for multiple credentials

.gitignore

@@ -32,3 +32,4 @@ coverage.out
 
 .envrc
 hetzner.json
+config.json

CHANGELOG.md

@@ -6,6 +6,10 @@
 
 * Switch to cloud.drone.io for CI
 
+### Added
+
+* Support multiple credentials and config file
+
 ## [0.2.0] - 2019-01-11
 
 ### Added

Gopkg.toml

@@ -53,3 +53,7 @@
 [prune]
   go-tests = true
   unused-packages = true
+
+[[constraint]]
+  branch = "v2"
+  name = "gopkg.in/yaml.v2"

cmd/prometheus-hetzner-sd/main.go

@@ -21,6 +21,9 @@ var (
 
 	// ErrMissingHetznerPassword defines the error if hetzner.password is empty.
 	ErrMissingHetznerPassword = errors.New("Missing required hetzner.password")
+
+	// ErrMissingAnyCredentials defines the error if no credentials are provided.
+	ErrMissingAnyCredentials = errors.New("Missing any credentials")
 )
 
 func main() {
@@ -90,23 +93,38 @@ func main() {
 						Destination: &cfg.Target.Refresh,
 					},
 					&cli.StringFlag{
-						Name:        "hetzner.username",
-						Value:       "",
-						Usage:       "Username for the Hetzner API",
-						EnvVars:     []string{"PROMETHEUS_HETZNER_USERNAME"},
-						Destination: &cfg.Target.Username,
+						Name:    "hetzner.username",
+						Value:   "",
+						Usage:   "Username for the Hetzner API",
+						EnvVars: []string{"PROMETHEUS_HETZNER_USERNAME"},
+					},
+					&cli.StringFlag{
+						Name:    "hetzner.password",
+						Value:   "",
+						Usage:   "Password for the Hetzner API",
+						EnvVars: []string{"PROMETHEUS_HETZNER_PASSWORD"},
 					},
 					&cli.StringFlag{
-						Name:        "hetzner.password",
-						Value:       "",
-						Usage:       "Password for the Hetzner API",
-						EnvVars:     []string{"PROMETHEUS_HETZNER_PASSWORD"},
-						Destination: &cfg.Target.Password,
+						Name:    "hetzner.config",
+						Value:   "",
+						Usage:   "Path to Hetzner configuration file",
+						EnvVars: []string{"PROMETHEUS_HETZNER_CONFIG"},
 					},
 				},
 				Action: func(c *cli.Context) error {
 					logger := setupLogger(cfg)
 
+					if c.IsSet("hetzner.config") {
+						if err := readConfig(c.String("hetzner.config"), cfg); err != nil {
+							level.Error(logger).Log(
+								"msg", "Failed to read config",
+								"err", err,
+							)
+
+							return err
+						}
+					}
+
 					if cfg.Target.File == "" {
 						level.Error(logger).Log(
 							"msg", ErrMissingOutputFile,
@@ -115,20 +133,41 @@ func main() {
 						return ErrMissingOutputFile
 					}
 
-					if cfg.Target.Username == "" {
-						level.Error(logger).Log(
-							"msg", ErrMissingHetznerUsername,
+					if c.IsSet("hetzner.username") && c.IsSet("hetzner.password") {
+						credentials := config.Credential{
+							Project:  "default",
+							Username: c.String("hetzner.username"),
+							Password: c.String("hetzner.password"),
+						}
+
+						cfg.Target.Credentials = append(
+							cfg.Target.Credentials,
+							credentials,
 						)
 
-						return ErrMissingHetznerUsername
+						if credentials.Username == "" {
+							level.Error(logger).Log(
+								"msg", ErrMissingHetznerUsername,
+							)
+
+							return ErrMissingHetznerUsername
+						}
+
+						if credentials.Password == "" {
+							level.Error(logger).Log(
+								"msg", ErrMissingHetznerPassword,
+							)
+
+							return ErrMissingHetznerPassword
+						}
 					}
 
-					if cfg.Target.Password == "" {
+					if len(cfg.Target.Credentials) == 0 {
 						level.Error(logger).Log(
-							"msg", ErrMissingHetznerPassword,
+							"msg", ErrMissingAnyCredentials,
 						)
 
-						return ErrMissingHetznerPassword
+						return ErrMissingAnyCredentials
 					}
 
 					return action.Server(cfg, logger)

cmd/prometheus-hetzner-sd/setup.go

@@ -1,14 +1,24 @@
 package main
 
 import (
+	"encoding/json"
+	"errors"
+	"gopkg.in/yaml.v2"
+	"io/ioutil"
 	"os"
+	"path/filepath"
 	"strings"
 
 	"github.com/go-kit/kit/log"
 	"github.com/go-kit/kit/log/level"
 	"github.com/promhippie/prometheus-hetzner-sd/pkg/config"
 )
 
+var (
+	// ErrConfigFormatInvalid defines the error if ext is unsupported.
+	ErrConfigFormatInvalid = errors.New("Config extension is not supported")
+)
+
 func setupLogger(cfg *config.Config) log.Logger {
 	var logger log.Logger
 
@@ -40,3 +50,30 @@ func setupLogger(cfg *config.Config) log.Logger {
 		"ts", log.DefaultTimestampUTC,
 	)
 }
+
+func readConfig(file string, cfg *config.Config) error {
+	if file == "" {
+		return nil
+	}
+
+	content, err := ioutil.ReadFile(file)
+
+	if err != nil {
+		return err
+	}
+
+	switch strings.ToLower(filepath.Ext(file)) {
+	case ".yaml", ".yml":
+		if err = yaml.Unmarshal(content, cfg); err != nil {
+			return err
+		}
+	case ".json":
+		if err = json.Unmarshal(content, cfg); err != nil {
+			return err
+		}
+	default:
+		return ErrConfigFormatInvalid
+	}
+
+	return nil
+}

config/example.json

@@ -0,0 +1,31 @@
+{
+	"server": {
+		"addr": "0.0.0.0:9000",
+		"path": "/metrics"
+	},
+	"logs": {
+		"level": "error",
+		"pretty": false
+	},
+	"target": {
+		"file": "/etc/prometheus/hetzner.json",
+		"refresh": 30,
+		"credentials": [
+			{
+				"project": "example1",
+				"username": "#ws+E9WaCWqg",
+				"password": "nmkEoHQWgnzThGmbfQ6Dojwf"
+			},
+			{
+				"project": "example2",
+				"username": "#ws+bmnA3gtt",
+				"password": "xapPbhgoRwEaRAHpKMnxa7YR"
+			},
+			{
+				"project": "example3",
+				"username": "#ws+Mk6uueNd",
+				"password": "YmmvhAXAeejpxWJxTzf9kjXm"
+			}
+		]
+	}
+}

config/example.yaml

@@ -0,0 +1,21 @@
+server:
+  addr: 0.0.0.0:9000
+  path: /metrics
+
+logs:
+  level: error
+  pretty: false
+
+target:
+  file: /etc/prometheus/hetzner.json
+  refresh: 30
+  credentials:
+  - project: example1
+    username: '#ws+E9WaCWqg'
+    password: nmkEoHQWgnzThGmbfQ6Dojwf
+  - project: example2
+    username: '#ws+bmnA3gtt'
+    password: xapPbhgoRwEaRAHpKMnxa7YR
+  - project: example3
+    username: '#ws+Mk6uueNd'
+    password: YmmvhAXAeejpxWJxTzf9kjXm

docs/content/getting-started.md

@@ -39,6 +39,13 @@ Currently we have not prepared a deployment for Kubernetes, but this is somethin
 
 ## Configuration
 
+### Envrionment variables
+
+If you prefer to configure the service with environment variables you can see the available variables below, in case you want to configure multiple accounts with a single service you are forced to use the configuration file as the environment variables are limited to a single account. As the service is pretty lightweight you can even start an instance per account and configure it entirely by the variables, it's up to you.
+
+PROMETHEUS_HETZNER_CONFIG
+: Path to Hetzner configuration file, optionally, required for muli credentials
+
 PROMETHEUS_HETZNER_USERNAME
 : Username for the Hetzner API, required for authentication
 
@@ -63,6 +70,10 @@ PROMETHEUS_HETZNER_OUTPUT_FILE
 PROMETHEUS_HETZNER_OUTPUT_REFRESH
 : Discovery refresh interval in seconds, defaults to `30`
 
+### Configuration file
+
+Especially if you want to configure multiple accounts within a single service discovery you got to use the configuration file. So far we support the file formats `JSON` and `YAML`, if you want to get a full example configuration just take a look at [our repository](https://github.com/promhippie/prometheus-hetzner-sd/tree/master/config), there you can always see the latest configuration format. These example configurations include all available options, they also include the default values.
+
 ## Labels
 
 * `__meta_hetzner_name`