add option to specify config.yaml

.gitignore

@@ -1,5 +1,6 @@
 .env
 .env_local
+.env.unset
 main
 tmp
 ./solidfire-exporter

README.md

@@ -16,20 +16,50 @@ Binaries can be downloaded from [Github releases](https://github.com/mjavier2k/s
 ### Usage
 
 ```
-./solidfire_exporter -u $SOLIDFIRE_USER -p $SOLIDFIRE_PASSWORD -e $SOLIDFIRE_ENDPOINT
+./solidfire_exporter --config config.yaml
 ```
 
 ```
 Usage of solidfire-exporter:
-  -l, --listenPort int    Port for the exporter to listen on. May also be set by environment variable SOLIDFIRE_PORT. (default 9987)
-  -u, --username string   User with which to authenticate to the Solidfire API. May also be set by environment variable SOLIDFIRE_USER. (default "my_solidfire_user")
-  -p, --password string   Password with which to authenticate to the Solidfire API. May also be set by environment variable SOLIDFIRE_PASS. (default "my_solidfire_password")
-  -e, --endpoint string   Endpoint for the Solidfire API. May also be set by environment variable SOLIDFIRE_RPC_ENDPOINT. (default "https://192.168.1.2/json-rpc/11.3")
-  -i, --insecure          Whether to disable TLS validation when calling the Solidfire API. May also be set by environment variable INSECURE_SKIP_VERIFY.
-  -t, --timeout int       HTTP Client timeout (in seconds) per call to Solidfire API. (default 30)
+  -c, --config string     Specify configuration filename. (default: config.yaml)
 ```
 
-__NOTE__: The account for __SOLIDFIRE_USER__ must have administrator access to the solidfire cluster so that QOS data will show up.
+
+### Configuration
+
+| Yaml Configuration Option | CLI Flag | Environment Variable      | Default                         | Example                            | Description                                                                                                                   |
+| ------------------------- | -------- | ------------------------- | ------------------------------- | ---------------------------------- | ----------------------------------------------------------------------------------------------------------------------------- |
+| client.username           | N/A      | SOLIDFIRE_CLIENT_USERNAME | ""                              | myUsername                         | User with which to authenticate to the Solidfire API. NOTE: User must have administrator access to be able to query QOS data. |
+| client.password           | N/A      | SOLIDFIRE_CLIENT_PASSWORD | ""                              | myPassword                         | Password with which to authenticate to the Solidfire API.                                                                     |
+| client.endpoint           | N/A      | SOLIDFIRE_CLIENT_ENDPOINT | https://127.0.0.1/json-rpc/11.3 | http://192.168.12.10/json-rpc/11.3 | HTTP(s) endpoint of the Solidfire API.                                                                                        |
+| client.insecure           | N/A      | SOLIDFIRE_CLIENT_INSECURE | false                           | true                               | Disables TLS validation when calling Solidfire API. Useful for bypassing self-signed certificates in testing.                 |
+| client.timeout            | N/A      | SOLIDFIRE_CLIENT_TIMEOUT  | 30                              | 75                                 | Timeout in seconds per call to the Solidfire API.                                                                             |
+| listen.address            | N/A      | SOLIDFIRE_LISTEN_ADDRESS  | 0.0.0.0:9987                    | 192.168.4.2:13987                  | IP address and port where the http server of this exporter should listen                                                      |
+| N/A                       | -c       | SOLIDFIRE_CONFIG          | config.yaml                     | mySolidfireConfig.yaml             | Path to configuration file                                                                                                    |
+
+1) Using config.yaml
+
+```
+listen:
+  address: 127.0.0.1:9987
+client:
+  endpoint: https://192.168.1.2/json-rpc/11.3
+  username: mySolidfireUsername
+  password: mySolidfirePassword
+  insecure: false
+  timeout: 130
+```
+
+2) Using environment variables. These option takes precedence if config.yaml is also specified.
+
+```
+export SOLIDFIRE_CLIENT_USERNAME="mySolidfireUsername"
+export SOLIDFIRE_CLIENT_PASSWORD="mySolidfirePassword"
+export SOLIDFIRE_LISTEN_ADDRESS="127.0.0.1:9987"
+export SOLIDFIRE_CLIENT_ENDPOINT="https://10.10.10.10/json-rpc/11.3"
+export SOLIDFIRE_CLIENT_INSECURE=true
+export SOLIDFIRE_CLIENT_TIMEOUT=30
+```
 
 ### Prometheus Configuration
 

cmd/solidfire-exporter/main.go

@@ -3,7 +3,8 @@ package main
 import (
 	"fmt"
 	"net/http"
-	"os"
+	"path/filepath"
+	"strings"
 
 	log "github.com/amoghe/distillog"
 	"github.com/mjavier2k/solidfire-exporter/pkg/prom"
@@ -20,43 +21,54 @@ var (
 )
 
 func init() {
-	flag.CommandLine.SortFlags = false
-	flag.IntP(solidfire.ListenPortFlag, "l", 9987, fmt.Sprintf("Port for the exporter to listen on. May also be set by environment variable %v.", solidfire.ListenPortFlagEnv))
-	flag.StringP(solidfire.UsernameFlag, "u", "my_solidfire_user", fmt.Sprintf("User with which to authenticate to the Solidfire API. May also be set by environment variable %v.", solidfire.UsernameFlagEnv))
-	flag.StringP(solidfire.PasswordFlag, "p", "my_solidfire_password", fmt.Sprintf("Password with which to authenticate to the Solidfire API. May also be set by environment variable %v.", solidfire.PasswordFlagEnv))
-	flag.StringP(solidfire.EndpointFlag, "e", "https://192.168.1.2/json-rpc/11.3", fmt.Sprintf("Endpoint for the Solidfire API. May also be set by environment variable %v.", solidfire.EndpointFlagEnv))
-	flag.BoolP(solidfire.InsecureSSLFlag, "i", false, fmt.Sprintf("Whether to disable TLS validation when calling the Solidfire API. May also be set by environment variable %v.", solidfire.InsecureSSLFlagEnv))
-	flag.Int64P(solidfire.HTTPClientTimeoutFlag, "t", 30, fmt.Sprintf("HTTP Client timeout (in seconds) per call to Solidfire API."))
+	flag.CommandLine.SortFlags = true
+	flag.StringP(solidfire.ConfigFile, "c", solidfire.DefaultConfigFile, fmt.Sprintf("Specify configuration filename."))
 	flag.Parse()
+	viper.BindPFlags(flag.CommandLine)
+
+	// extracts the filename from the config filename passed on --config flag (e.g /etc/solidfire-exporter/config.yaml)
+	viper.SetConfigName(filepath.Base(viper.GetString(solidfire.ConfigFile)))
+	viper.SetConfigType("yaml")
+	// extracts the directory path from the config filename passed on --config flag (e.g /etc/solidfire-exporter/config.yaml)
+	viper.AddConfigPath(filepath.Dir(viper.GetString(solidfire.ConfigFile)))
+	viper.AddConfigPath(".")
 
-	// PORT environment variable takes precedence in order to be backwards-compatible
-	if legacyPort, legacyPortFlagExists := os.LookupEnv("PORT"); legacyPortFlagExists {
-		viper.BindEnv(solidfire.ListenPortFlag, "PORT")
-		log.Warningf("Found environment variable PORT=%v, skipping lookup of %v", legacyPort, solidfire.ListenPortFlagEnv)
+	if err := viper.ReadInConfig(); err != nil {
+		if _, ok := err.(viper.ConfigFileNotFoundError); ok {
+			log.Infof("No config file found.")
+		}
 	} else {
-		viper.BindEnv(solidfire.ListenPortFlag, solidfire.ListenPortFlagEnv)
+		log.Infof("Found configuration file on %v ", viper.GetViper().ConfigFileUsed())
 	}
 
-	viper.BindEnv(solidfire.UsernameFlag, solidfire.UsernameFlagEnv)
-	viper.BindEnv(solidfire.PasswordFlag, solidfire.PasswordFlagEnv)
-	viper.BindEnv(solidfire.EndpointFlag, solidfire.EndpointFlagEnv)
-	viper.BindEnv(solidfire.InsecureSSLFlag, solidfire.InsecureSSLFlagEnv)
-	viper.BindPFlags(flag.CommandLine)
+	viper.SetDefault(solidfire.ListenAddress, solidfire.DefaultListenAddress)
+	viper.SetDefault(solidfire.Endpoint, solidfire.DefaultEndpoint)
+	viper.SetDefault(solidfire.HTTPClientTimeout, solidfire.DefaultHTTPClientTimeout)
+
+	viper.AutomaticEnv()
+	viper.SetEnvPrefix("SOLIDFIRE")
+	viper.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
 }
 func main() {
 	log.Infof("Version: %v", sha1ver)
 	log.Infof("Built: %v", buildTime)
-	listenAddr := fmt.Sprintf("0.0.0.0:%v", viper.GetInt(solidfire.ListenPortFlag))
+	listenAddress := fmt.Sprintf("%v", viper.GetString(solidfire.ListenAddress))
 	solidfireExporter, _ := prom.NewCollector()
 	prometheus.MustRegister(solidfireExporter)
 	http.Handle("/metrics", promhttp.Handler())
-	log.Infof("Booted and listening on %v/metrics\n", listenAddr)
-
+	for _, key := range viper.AllKeys() {
+		value := viper.Get(key)
+		if key == solidfire.Password {
+			value = "[REDACTED]"
+		}
+		log.Infof("Config setting found for %s: %v", key, value)
+	}
+	log.Infof("Booted and listening on %v/metrics\n", listenAddress)
 	http.HandleFunc("/health", func(w http.ResponseWriter, r *http.Request) {
 		fmt.Fprintf(w, "UP")
 	})
 
-	err := http.ListenAndServe(listenAddr, nil)
+	err := http.ListenAndServe(listenAddress, nil)
 	if err != nil {
 		log.Errorln(err)
 	}

config.yaml.example

@@ -0,0 +1,8 @@
+listen:
+  address: 127.0.0.1:9987
+client:
+  endpoint: https://192.168.1.2/json-rpc/11.3
+  username: mySolidfireUsername
+  password: mySolidfirePassword
+  insecure: false
+  timeout: 130

pkg/solidfire/solidfire.go

@@ -16,24 +16,24 @@ import (
 func NewSolidfireClient() *Client {
 	log.Infof("initializing new solidfire client")
 
-	insecure := viper.GetBool(InsecureSSLFlag)
+	insecure := viper.GetBool(InsecureSSL)
 	if insecure {
 		log.Warningln("TLS certificate verification is currently disabled - This is not recommended.")
 	}
 
-	log.Infoln("RPC Server:", viper.GetString(EndpointFlag))
+	log.Infoln("RPC Server:", viper.GetString(Endpoint))
 
 	tr := &http.Transport{
 		TLSClientConfig: &tls.Config{InsecureSkipVerify: insecure},
 	}
 	return &Client{
 		HttpClient: &http.Client{
 			Transport: tr,
-			Timeout:   time.Duration(viper.GetInt64(HTTPClientTimeoutFlag)) * time.Second,
+			Timeout:   time.Duration(viper.GetInt64(HTTPClientTimeout)) * time.Second,
 		},
-		Username:    viper.GetString(UsernameFlag),
-		Password:    viper.GetString(PasswordFlag),
-		RPCEndpoint: viper.GetString(EndpointFlag),
+		Username:    viper.GetString(Username),
+		Password:    viper.GetString(Password),
+		RPCEndpoint: viper.GetString(Endpoint),
 	}
 }
 

pkg/solidfire/types.go

@@ -6,17 +6,21 @@ import (
 )
 
 var (
-	ListenPortFlag        = "listenPort"
-	UsernameFlag          = "username"
-	PasswordFlag          = "password"
-	EndpointFlag          = "endpoint"
-	InsecureSSLFlag       = "insecure"
-	HTTPClientTimeoutFlag = "timeout"
-	ListenPortFlagEnv     = "SOLIDFIRE_PORT"
-	UsernameFlagEnv       = "SOLIDFIRE_USER"
-	PasswordFlagEnv       = "SOLIDFIRE_PASS"
-	EndpointFlagEnv       = "SOLIDFIRE_RPC_ENDPOINT"
-	InsecureSSLFlagEnv    = "INSECURE_SKIP_VERIFY"
+	ListenAddress        = "listen.address"
+	DefaultListenAddress = "0.0.0.0:9987"
+
+	Username = "client.username"
+	Password = "client.password"
+
+	Endpoint        = "client.endpoint"
+	DefaultEndpoint = "http://127.0.0.1/json-rpc/11.3"
+	InsecureSSL     = "client.insecure"
+
+	HTTPClientTimeout        = "client.timeout"
+	DefaultHTTPClientTimeout = 30
+
+	ConfigFile        = "config"
+	DefaultConfigFile = "config.yaml"
 )
 
 type Client struct {