Cleanup deprecated api usage (ioutil -> io and os)

couchdb-exporter_test.go

@@ -3,12 +3,12 @@ package main
 import (
 	"encoding/base64"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"net"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"os"
 	"strings"
 	"testing"
 	"time"
@@ -61,7 +61,7 @@ func BasicAuthHandler(basicAuth lib.BasicAuth, pass Handler) Handler {
 }
 
 func readFile(t *testing.T, filename string) []byte {
-	fileContent, err := ioutil.ReadFile(filename)
+	fileContent, err := os.ReadFile(filename)
 	if err != nil {
 		t.Errorf("Error reading file %s: %v\n", filename, err)
 	}

fileutil/properties_file_loader.go

@@ -6,7 +6,7 @@ import (
 	"bufio"
 	"bytes"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"log"
 	"net/http"
 	"net/url"
@@ -109,21 +109,21 @@ func loadDataFrom(filePath string) ([]byte, error) {
 			if err != nil {
 				return nil, err
 			}
-			return ioutil.ReadAll(res.Body)
+			return io.ReadAll(res.Body)
 		default:
 			return nil, fmt.Errorf("scheme of %s is unsupported", filePath)
 		}
-	} else if u.Path != "" { // i dont have a host, but I have a path. I am a local file.
+	} else if u.Path != "" { // I don't have a host, but I have a path. I am a local file.
 		if _, notFoundFileErr := os.Stat(filePath); notFoundFileErr != nil {
 			return nil, fmt.Errorf("cannot read from file: '%s' because it does not exist", filePath)
 		}
-		return ioutil.ReadFile(filePath)
+		return os.ReadFile(filePath)
 	} else if runtime.GOOS == "windows" && strings.Contains(u.String(), "\\") {
 		// on Windows systems u.Path is always empty, so we need to check the string directly.
 		if _, notFoundFileErr := os.Stat(filePath); notFoundFileErr != nil {
 			return nil, fmt.Errorf("cannot read from file: '%s' because it does not exist", filePath)
 		}
-		return ioutil.ReadFile(filePath)
+		return os.ReadFile(filePath)
 	} else {
 		return nil, fmt.Errorf("unable to determine how to load from path %s", filePath)
 	}

lib/couchdb-client.go

@@ -6,7 +6,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/url"
 	"strconv"
@@ -575,7 +574,7 @@ func (c *CouchdbClient) Request(method string, uri string, body io.Reader) (resp
 		}()
 	}
 
-	respData, err = ioutil.ReadAll(resp.Body)
+	respData, err = io.ReadAll(resp.Body)
 	if resp.StatusCode < 200 || resp.StatusCode >= 400 {
 		if err != nil {
 			respData = []byte(err.Error())