all: comply with linters

Fix the code as recommended by linters, for example using context for
HTTP client request, using 0600 for file permission, using string
concatenation instead of fmt, using "%w" for error, and reorder defer.

6 files changed, 40 insertions, 34 deletions

diff --git a/Makefile b/Makefile
index 0bc49c8..a13040b 100644
--- a/Makefile
+++ b/Makefile
@@ -71,10 +71,14 @@ test.prof:
 
 .PHONY: lint
 lint:
-	-go vet ./...
 	-fieldalignment ./...
 	-shadow ./...
-	-revive ./...
+	-golangci-lint run \
+		--presets bugs,metalinter,performance,unused \
+		--disable exhaustive \
+		--disable musttag \
+		--disable bodyclose \
+		./...
 	-reuse --suppress-deprecation lint
 
 
diff --git a/blockd.go b/blockd.go
index f1d4b9b..021f7c3 100644
--- a/blockd.go
+++ b/blockd.go
@@ -5,6 +5,7 @@ package rescached
 
 import (
 	"bytes"
+	"context"
 	"fmt"
 	"io"
 	"log"
@@ -100,13 +101,7 @@ func (hb *Blockd) update() (err error) {
 		return nil
 	}
 
-	var (
-		logp = "Blockd.update"
-
-		res      *http.Response
-		body     []byte
-		errClose error
-	)
+	var logp = `Blockd.update`
 
 	fmt.Printf("%s %s: updating ...\n", logp, hb.Name)
 
@@ -115,17 +110,27 @@ func (hb *Blockd) update() (err error) {
 		return fmt.Errorf("%s %s: %w", logp, hb.Name, err)
 	}
 
-	res, err = http.Get(hb.URL)
+	var (
+		req *http.Request
+		res *http.Response
+	)
+	req, err = http.NewRequestWithContext(context.Background(), http.MethodGet, hb.URL, nil)
+	if err != nil {
+		return fmt.Errorf(`%s %s: %w`, logp, hb.Name, err)
+	}
+	res, err = http.DefaultClient.Do(req)
 	if err != nil {
 		return fmt.Errorf("%s %s: %w", logp, hb.Name, err)
 	}
 	defer func() {
-		errClose = res.Body.Close()
+		var errClose = res.Body.Close()
 		if errClose != nil {
 			log.Printf("%s %q: %s", logp, hb.Name, err)
 		}
 	}()
 
+	var body []byte
+
 	body, err = io.ReadAll(res.Body)
 	if err != nil {
 		return fmt.Errorf("%s %q: %w", logp, hb.Name, err)
@@ -134,9 +139,9 @@ func (hb *Blockd) update() (err error) {
 	body = bytes.ReplaceAll(body, []byte("\r\n"), []byte("\n"))
 
 	if hb.IsEnabled {
-		err = os.WriteFile(hb.file, body, 0644)
+		err = os.WriteFile(hb.file, body, 0600)
 	} else {
-		err = os.WriteFile(hb.fileDisabled, body, 0644)
+		err = os.WriteFile(hb.fileDisabled, body, 0600)
 	}
 	if err != nil {
 		return fmt.Errorf("%s %q: %w", logp, hb.Name, err)
diff --git a/client_test.go b/client_test.go
index 8398004..711b626 100644
--- a/client_test.go
+++ b/client_test.go
@@ -108,7 +108,7 @@ func TestClient_BlockdFetch(t *testing.T) {
 
 	// Revert the content of a.block.
 	t.Cleanup(func() {
-		err = os.WriteFile(affectedBlockd.fileDisabled, []byte("127.0.0.1 a.block\n"), 0644)
+		err = os.WriteFile(affectedBlockd.fileDisabled, []byte("127.0.0.1 a.block\n"), 0600)
 	})
 
 	expString = `BlockdFetch: 400 httpAPIBlockdFetch: unknown hosts block.d name: xxx`
diff --git a/environment.go b/environment.go
index be46b94..22a8ef1 100644
--- a/environment.go
+++ b/environment.go
@@ -98,12 +98,12 @@ func LoadEnvironment(dirBase, fileConfig string) (env *Environment, err error) {
 	if len(fileConfig) > 0 {
 		cfg, err = ini.Open(env.fileConfig)
 		if err != nil {
-			return nil, fmt.Errorf("%s: %q: %s", logp, env.fileConfig, err)
+			return nil, fmt.Errorf(`%s: %q: %w`, logp, env.fileConfig, err)
 		}
 
 		err = cfg.Unmarshal(env)
 		if err != nil {
-			return nil, fmt.Errorf("%s: %q: %s", logp, env.fileConfig, err)
+			return nil, fmt.Errorf(`%s: %q: %w`, logp, env.fileConfig, err)
 		}
 	}
 
@@ -254,8 +254,8 @@ func (env *Environment) save(file string) (in *ini.Ini, err error) {
 	in.Set(sectionNameDNS, subNameServer, keyTLSPort, strconv.Itoa(int(env.TLSPort)))
 	in.Set(sectionNameDNS, subNameServer, keyTLSCertificate, env.TLSCertFile)
 	in.Set(sectionNameDNS, subNameServer, keyTLSPrivateKey, env.TLSPrivateKey)
-	in.Set(sectionNameDNS, subNameServer, keyTLSAllowInsecure, fmt.Sprintf("%t", env.TLSAllowInsecure))
-	in.Set(sectionNameDNS, subNameServer, keyDohBehindProxy, fmt.Sprintf("%t", env.DoHBehindProxy))
+	in.Set(sectionNameDNS, subNameServer, keyTLSAllowInsecure, strconv.FormatBool(env.TLSAllowInsecure))
+	in.Set(sectionNameDNS, subNameServer, keyDohBehindProxy, strconv.FormatBool(env.DoHBehindProxy))
 
 	in.Set(sectionNameDNS, subNameServer, keyCachePruneDelay, env.PruneDelay.String())
 	in.Set(sectionNameDNS, subNameServer, keyCachePruneThreshold, env.PruneThreshold.String())
diff --git a/httpd.go b/httpd.go
index b872f30..f42a2b3 100644
--- a/httpd.go
+++ b/httpd.go
@@ -370,7 +370,7 @@ func (srv *Server) httpAPIBlockdDisable(epr *libhttp.EndpointRequest) (resBody [
 	hb = srv.env.HostBlockd[hbName]
 	if hb == nil {
 		res.Code = http.StatusBadRequest
-		res.Message = fmt.Sprintf("hosts block.d name not found: %s", hbName)
+		res.Message = `hosts block.d name not found: ` + hbName
 		return nil, &res
 	}
 
@@ -419,7 +419,7 @@ func (srv *Server) httpAPIBlockdEnable(epr *libhttp.EndpointRequest) (resBody []
 	hb = srv.env.HostBlockd[hbName]
 	if hb == nil {
 		res.Code = http.StatusBadRequest
-		res.Message = fmt.Sprintf("hosts block.d name not found: %s", hbName)
+		res.Message = `hosts block.d name not found: ` + hbName
 		return nil, &res
 	}
 
@@ -1197,10 +1197,6 @@ func (srv *Server) apiZonedDelete(epr *libhttp.EndpointRequest) (resb []byte, er
 	var (
 		res      = libhttp.EndpointResponse{}
 		zoneName = epr.HTTPRequest.Form.Get(paramNameName)
-
-		zone  *dns.Zone
-		names []string
-		name  string
 	)
 
 	res.Code = http.StatusBadRequest
@@ -1210,13 +1206,16 @@ func (srv *Server) apiZonedDelete(epr *libhttp.EndpointRequest) (resb []byte, er
 		return nil, &res
 	}
 
-	zone = srv.env.zoned[zoneName]
+	var zone = srv.env.zoned[zoneName]
 	if zone == nil {
 		res.Message = "zone file not found: " + zoneName
 		return nil, &res
 	}
 
-	names = make([]string, 0, len(zone.Records))
+	var (
+		names = make([]string, 0, len(zone.Records))
+		name  string
+	)
 	for name = range zone.Records {
 		names = append(names, name)
 	}
@@ -1331,7 +1330,7 @@ func (srv *Server) apiZonedRRAdd(epr *libhttp.EndpointRequest) (resb []byte, err
 
 	err = json.Unmarshal(epr.RequestBody, &req)
 	if err != nil {
-		res.Message = fmt.Sprintf("invalid request: %s", err.Error())
+		res.Message = `invalid request: ` + err.Error()
 		return nil, &res
 	}
 
@@ -1355,7 +1354,7 @@ func (srv *Server) apiZonedRRAdd(epr *libhttp.EndpointRequest) (resb []byte, err
 
 	req.recordRaw, err = base64.StdEncoding.DecodeString(req.Record)
 	if err != nil {
-		res.Message = fmt.Sprintf("invalid record value: %s", err.Error())
+		res.Message = `invalid record value: ` + err.Error()
 		return nil, &res
 	}
 
@@ -1417,7 +1416,7 @@ func (srv *Server) apiZonedRRAdd(epr *libhttp.EndpointRequest) (resb []byte, err
 	}
 
 	res.Code = http.StatusOK
-	res.Message = fmt.Sprintf("%s record has been saved", dns.RecordTypeNames[rr.Type])
+	res.Message = dns.RecordTypeNames[rr.Type] + ` record has been saved`
 	res.Data = rr
 
 	return json.Marshal(&res)
@@ -1477,7 +1476,7 @@ func (srv *Server) apiZonedRRDelete(epr *libhttp.EndpointRequest) (resbody []byt
 	req.Record = epr.HTTPRequest.Form.Get(paramNameRecord)
 	req.recordRaw, err = base64.StdEncoding.DecodeString(req.Record)
 	if err != nil {
-		res.Message = fmt.Sprintf("invalid record value: %s", err.Error())
+		res.Message = `invalid record value: ` + err.Error()
 		return nil, &res
 	}
 
diff --git a/rescached_test.go b/rescached_test.go
index d312c2a..0e51afa 100644
--- a/rescached_test.go
+++ b/rescached_test.go
@@ -46,8 +46,6 @@ func TestMain(m *testing.M) {
 		log.Fatal(err)
 	}
 
-	defer testServer.Stop()
-
 	resc = NewClient("http://"+testEnv.WUIListen, false)
 
 	// Loop 10 times until server ready for testing.
@@ -61,7 +59,7 @@ func TestMain(m *testing.M) {
 	}
 
 	testStatus = m.Run()
-
+	testServer.Stop()
 	os.Exit(testStatus)
 }
 
@@ -103,6 +101,6 @@ func mockBlockdServer() {
 
 	err = mockServer.Start()
 	if err != nil {
-		log.Fatal(err)
+		log.Println(err)
 	}
 }