Merge pull request #1243 from DiniFarb/master

Load config file from URL

README.md

@@ -89,6 +89,8 @@ Flag     | Description | Default value
 `--collectors.print` | If true, print available collectors and exit. |
 `--scrape.timeout-margin` | Seconds to subtract from the timeout allowed by the client. Tune to allow for overhead or high loads. | `0.5`
 `--web.config.file` | A [web config][web_config] for setting up TLS and Auth | None
+`--config.file` | [Using a config file](#using-a-configuration-file) from path or URL | None
+`--config.file.insecure-skip-verify` | Skip TLS when loading config file from URL | false
 
 ## Installation
 The latest release can be downloaded from the [releases page](https://github.com/prometheus-community/windows_exporter/releases).
@@ -173,6 +175,10 @@ This enables the additional process and container collectors on top of the defau
 
 YAML configuration files can be specified with the `--config.file` flag. e.g. `.\windows_exporter.exe --config.file=config.yml`. If you are using the absolute path, make sure to quote the path, e.g. `.\windows_exporter.exe --config.file="C:\Program Files\windows_exporter\config.yml"`
 
+It is also possible to load the configuration from a URL. e.g. `.\windows_exporter.exe --config.file="https://example.com/config.yml"`
+
+If you need to skip TLS verification, you can use the `--config.file.insecure-skip-verify` flag. e.g. `.\windows_exporter.exe --config.file="https://example.com/config.yml" --config.file.insecure-skip-verify`
+
 ```yaml
 collectors:
   enabled: cpu,cs,net,service

config/config.go

@@ -14,7 +14,11 @@
 package config
 
 import (
+	"crypto/tls"
 	"fmt"
+	"io"
+	"net/http"
+	"net/url"
 	"os"
 
 	"github.com/alecthomas/kingpin/v2"
@@ -33,19 +37,44 @@ type Resolver struct {
 }
 
 // NewResolver returns a Resolver structure.
-func NewResolver(file string, logger log.Logger) (*Resolver, error) {
+func NewResolver(file string, logger log.Logger, insecure_skip_verify bool) (*Resolver, error) {
 	flags := map[string]string{}
+	var fileBytes []byte
+	url, err := url.ParseRequestURI(file)
+	if err != nil {
+		return nil, err
+	}
+	if url.Scheme == "http" || url.Scheme == "https" {
+		_ = level.Info(logger).Log("msg", fmt.Sprintf("Loading configuration file from URL: %v", file))
+		tr := &http.Transport{
+			TLSClientConfig: &tls.Config{InsecureSkipVerify: insecure_skip_verify},
+		}
+		if insecure_skip_verify {
+			_ = level.Warn(logger).Log("msg", "Loading configuration file with TLS verification disabled")
+		}
+		client := &http.Client{Transport: tr}
+		resp, err := client.Get(file)
+		if err != nil {
+			return nil, err
+		}
+		defer resp.Body.Close()
+		fileBytes, err = io.ReadAll(resp.Body)
+		if err != nil {
+			return nil, err
+		}
+	} else {
 		_ = level.Info(logger).Log("msg", fmt.Sprintf("Loading configuration file: %v", file))
 		if _, err := os.Stat(file); err != nil {
 			return nil, err
 		}
-	b, err := os.ReadFile(file)
+		fileBytes, err = os.ReadFile(file)
 		if err != nil {
 			return nil, err
 		}
+	}
 
 	var rawValues map[string]interface{}
-	err = yaml.Unmarshal(b, &rawValues)
+	err = yaml.Unmarshal(fileBytes, &rawValues)
 	if err != nil {
 		return nil, err
 	}

exporter.go

@@ -105,6 +105,10 @@ func main() {
 			"config.file",
 			"YAML configuration file to use. Values set in this file will be overridden by CLI flags.",
 		).String()
+		insecure_skip_verify = app.Flag(
+			"config.file.insecure-skip-verify",
+			"Skip TLS verification in loading YAML configuration.",
+		).Default("false").Bool()
 		webConfig   = webflag.AddFlags(app, ":9182")
 		metricsPath = app.Flag(
 			"telemetry.path",
@@ -152,7 +156,7 @@ func main() {
 
 	_ = level.Debug(logger).Log("msg", "Logging has Started")
 	if *configFile != "" {
-		resolver, err := config.NewResolver(*configFile, logger)
+		resolver, err := config.NewResolver(*configFile, logger, *insecure_skip_verify)
 		if err != nil {
 			_ = level.Error(logger).Log("msg", "could not load config file", "err", err)
 			os.Exit(1)