Rework a bit the logs + readme

README.md

@@ -1,2 +1,82 @@
 # freebox-exporter
-Prometheus exporter for the Freebox
+
+Prometheus exporter for the [Freebox](https://www.free.fr/freebox/)
+
+**Disclaimer**: I am not related to Iliad, Free or any of their subsidiaries. I have only created this Prometheus exporter to monitor my own device using some [publicly available documentation](https://dev.freebox.fr/sdk/os/).
+
+## Install
+
+Having a working Golang environment using Go modules:
+
+```bash
+go install github.com/trazfr/freebox-exporter@latest
+```
+
+## Use
+
+This program is to be run in 2 steps, as you must authorize the exporter to access the Freebox. Once authorized, it may be run from anywhere.
+
+```
+Usage: freebox-exporter [options] <api_token_file>
+
+api_token_file: file to store the token for the API
+
+options:
+  -debug
+        enable the debug mode
+  -hostDetails
+        get details about the hosts connected to wifi and ethernet. This increases the number of metrics
+  -httpDiscovery
+        use http://mafreebox.freebox.fr/api_version to discover the Freebox at the first run (by default: use mDNS)
+  -listen string
+        listen to address (default ":9091")
+```
+
+### Step 1 authorize API
+
+From the Freebox network, generate a token file for the API. The file `token.json` must not exist:
+
+```bash
+$ freebox-exporter token.json
+Could not find the configuration file token.json
+Freebox discovery: mDNS
+1 Please accept the login on the Freebox Server
+...
+```
+
+You must accept the API on the Freebox device.
+
+Once done, the credentials will be stored in the new file `token.json`
+
+**In case of errors**:
+
+If you get the message `panic: Access is timeout`, you have to be faster to accept the access on the Freebox.
+
+If you get the message `panic: MDNS timeout`, there may be a firewall preventing you to use mDNS. You may try to get the token using HTTP:
+
+```bash
+$ freebox-exporter -httpDiscovery token.json
+Could not find the configuration file token.json
+Freebox discovery: GET http://mafreebox.freebox.fr/api_version
+1 Please accept the login on the Freebox Server
+...
+```
+
+### Step 2 run
+
+Once you have generated the token you may run from anywhere.
+
+```bash
+$ freebox-exporter token.json
+Use configuration file token.json
+Listen to :9091
+```
+
+Then you may test it:
+
+```bash
+$ curl 127.0.0.1:9091/metrics
+# HELP freebox_connection_bandwith_bps available upload/download bandwidth in bit/s
+# TYPE freebox_connection_bandwith_bps gauge
+...
+```

fbx/api_version.go

@@ -46,7 +46,7 @@ func NewFreeboxAPIVersion(client *FreeboxHttpClient, discovery FreeboxDiscovery)
 	if result.IsValid() == false {
 		return nil, errors.New("Could not get the API version")
 	}
-	log.Info.Println("APIVersion", result)
+	log.Debug.Println("APIVersion", result)
 	return result, nil
 }
 

log/log.go

@@ -1,8 +1,9 @@
 package log
 
 import (
-	"io"
+	"io/ioutil"
 	"log"
+	"os"
 )
 
 var (
@@ -12,25 +13,27 @@ var (
 	Error   *log.Logger
 )
 
-func Init(
-	debugHandle io.Writer,
-	infoHandle io.Writer,
-	warningHandle io.Writer,
-	errorHandle io.Writer) {
-
-	Debug = log.New(debugHandle,
+func InitDebug() {
+	Debug = log.New(os.Stdout,
 		"DEBUG: ",
 		log.Ldate|log.Ltime|log.Lshortfile)
 
-	Info = log.New(infoHandle,
+	Info = log.New(os.Stdout,
 		"INFO: ",
 		log.Ldate|log.Ltime|log.Lshortfile)
 
-	Warning = log.New(warningHandle,
+	Warning = log.New(os.Stdout,
 		"WARNING: ",
 		log.Ldate|log.Ltime|log.Lshortfile)
 
-	Error = log.New(errorHandle,
+	Error = log.New(os.Stderr,
 		"ERROR: ",
 		log.Ldate|log.Ltime|log.Lshortfile)
 }
+
+func Init() {
+	Debug = log.New(ioutil.Discard, "", 0)
+	Info = log.New(os.Stdout, "", 0)
+	Warning = log.New(os.Stdout, "", 0)
+	Error = log.New(os.Stderr, "", 0)
+}

main.go

@@ -1,10 +1,8 @@
 package main
 
 import (
-	"errors"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"net/http"
 	"os"
 
@@ -15,34 +13,39 @@ import (
 	"github.com/trazfr/freebox-exporter/log"
 )
 
-func usage(err error) {
-	if err != nil {
-		fmt.Fprintln(os.Stderr, "Error:", err)
-	}
-	fmt.Fprintln(os.Stderr, "Usage:", os.Args[0], "[options] <api_token_file>")
-	fmt.Fprintln(os.Stderr)
-	fmt.Fprintln(os.Stderr, "Options:")
+func usage() {
+	fmt.Fprintf(flag.CommandLine.Output(),
+		"Usage: %s [options] <api_token_file>\n"+
+			"\n"+
+			"api_token_file: file to store the token for the API\n"+
+			"\n"+
+			"options:\n",
+		os.Args[0])
 	flag.PrintDefaults()
-	os.Exit(-1)
 }
 
 func main() {
+	flag.Usage = usage
 	debugPtr := flag.Bool("debug", false, "enable the debug mode")
 	hostDetailsPtr := flag.Bool("hostDetails", false, "get details about the hosts connected to wifi and ethernet. This increases the number of metrics")
-	httpDiscoveryPtr := flag.Bool("httpDiscovery", false, "use http://mafreebox.freebox.fr/api_version to discover the Freebox at the first run (default: mDNS)")
+	httpDiscoveryPtr := flag.Bool("httpDiscovery", false, "use http://mafreebox.freebox.fr/api_version to discover the Freebox at the first run (by default: use mDNS)")
 	listenPtr := flag.String("listen", ":9091", "listen to address")
 	flag.Parse()
 
 	args := flag.Args()
 	if len(args) < 1 {
-		usage(errors.New("api_token_file not defined"))
+		fmt.Fprintf(flag.CommandLine.Output(), "ERROR: api_token_file not defined\n")
+		usage()
+		os.Exit(1)
 	} else if len(args) > 1 {
-		usage(errors.New("too many arguments"))
+		fmt.Fprintf(flag.CommandLine.Output(), "ERROR: too many arguments\n")
+		usage()
+		os.Exit(1)
 	}
 	if *debugPtr {
-		log.Init(os.Stdout, os.Stdout, os.Stdout, os.Stderr)
+		log.InitDebug()
 	} else {
-		log.Init(ioutil.Discard, os.Stdout, os.Stdout, os.Stderr)
+		log.Init()
 	}
 	discovery := fbx.FreeboxDiscoveryMDNS
 	if *httpDiscoveryPtr {
@@ -55,5 +58,6 @@ func main() {
 	prometheus.MustRegister(collector)
 
 	http.Handle("/metrics", promhttp.Handler())
+	log.Info.Println("Listen to", *listenPtr)
 	log.Error.Println(http.ListenAndServe(*listenPtr, nil))
 }