chore(golangci-lint): add new linters and reformat code for compliance

- godot
- perfsprint
- whitespace
- unconvert
- unused
- usestdlibvars

.golangci.yml

@@ -9,11 +9,25 @@ linters:
     - errorlint
     - gci
     - gocritic
+    - godot
     - goimports
     - misspell
+    - perfsprint
     - typecheck
+    - whitespace
     - wrapcheck
+    - unconvert
+    - unused
+    - usestdlibvars
 
 linters-settings:
+  gci:
+    sections:
+      - standard
+      - default
+      - prefix(github.com/release-argus/Argus)
   goimports:
-    local-prefixes: github.com/release-argus/Argus
+    local-prefixes: github.com/release-argus/Argus
+  perfsprint:
+    # Optimises into `err.Error()` even if it is only equivalent for non-nil errors.
+    err-error: true

config/save.go

@@ -120,7 +120,6 @@ func (c *Config) Save() {
 		if indents == 1 &&
 			strings.HasSuffix(line, ":") &&
 			parentKey[0] == "service" {
-
 			// First service will be on 1 because we remove items and decrement
 			// currentOrderIndexEnd[currentServiceNumber]. So we want to know when the service
 			// has started so that the decrements are direct to the service.
@@ -278,7 +277,7 @@ func (c *Config) Save() {
 			c.File, err),
 		logutil.LogFrom{}, err != nil)
 	logutil.Log.Info(
-		fmt.Sprintf("Saved service updates to %s", c.File),
+		"Saved service updates to "+c.File,
 		logutil.LogFrom{}, true)
 }
 

config/settings.go

@@ -60,7 +60,7 @@ func (s *Settings) String(prefix string) string {
 
 // SettingsBase for the binary.
 //
-// (Used in Defaults)
+// (Used in Defaults).
 type SettingsBase struct {
 	Log  LogSettings  `yaml:"log,omitempty"`  // Log settings
 	Data DataSettings `yaml:"data,omitempty"` // Data settings

notify/shoutrrr/defaults.go

@@ -15,6 +15,8 @@
 // Package shoutrrr provides the shoutrrr notification service to services.
 package shoutrrr
 
+import "net/http"
+
 // notifyDefaultOptions are the default options for all notifiers.
 func notifyDefaultOptions() map[string]string {
 	return map[string]string{
@@ -143,7 +145,7 @@ func (s *SliceDefaults) Default() {
 			"contenttype":   "application/json",
 			"disabletls":    "no",
 			"messagekey":    "message",
-			"requestmethod": "POST",
+			"requestmethod": http.MethodPost,
 			"titlekey":      "title"})
 	newSlice["shoutrrr"] = NewDefaults(
 		"",

notify/shoutrrr/new.go

@@ -16,6 +16,7 @@
 package shoutrrr
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/release-argus/Argus/notify/shoutrrr/types"
@@ -50,7 +51,7 @@ func FromPayload(
 ) (*Shoutrrr, string, error) {
 	// No `name` or `name_previous`.
 	if payload.NamePrevious == "" && payload.Name == "" {
-		return nil, "", fmt.Errorf("name and/or name_previous are required")
+		return nil, "", errors.New("name and/or name_previous are required")
 	}
 
 	name := util.FirstNonDefault(payload.Name, payload.NamePrevious)

notify/shoutrrr/shoutrrr.go

@@ -182,8 +182,7 @@ func (s *Shoutrrr) BuildURL() (url string) {
 	case "googlechat":
 		url = s.GetURLField("raw")
 		// googlechat://url
-		url = fmt.Sprintf("googlechat://%s",
-			url)
+		url = "googlechat://" + url
 	case "ifttt":
 		// ifttt://webhookid/?events=event1,event2
 		url = fmt.Sprintf("ifttt://%s/?events=%s",
@@ -448,7 +447,7 @@ func (s *Shoutrrr) send(
 		func() error {
 			err := sender.Send(message, params)
 			if failed := s.parseSend(err, combinedErrs, serviceName, logFrom); failed {
-				return fmt.Errorf("send failed")
+				return errors.New("send failed")
 			}
 			return nil
 		},

notify/shoutrrr/verify.go

@@ -24,6 +24,7 @@ import (
 	"time"
 
 	goshoutrrr "github.com/containrrr/shoutrrr"
+
 	"github.com/release-argus/Argus/util"
 )
 

service/deployed_version/query.go

@@ -17,6 +17,7 @@ package deployedver
 
 import (
 	"crypto/tls"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -213,7 +214,7 @@ func (l *Lookup) httpRequest(logFrom logutil.LogFrom) ([]byte, error) {
 	if err != nil {
 		// Don't crash on invalid certs.
 		if strings.Contains(err.Error(), "x509") {
-			err = fmt.Errorf("x509 (certificate invalid)")
+			err = errors.New("x509 (certificate invalid)")
 			logutil.Log.Warn(err, logFrom, true)
 			return nil, err
 		}

service/deployed_version/refresh.go

@@ -32,7 +32,7 @@ func (l *Lookup) Refresh(
 	semanticVersioning *string,
 ) (string, error) {
 	if l == nil {
-		return "", fmt.Errorf("lookup is nil")
+		return "", errors.New("lookup is nil")
 	}
 	logFrom := logutil.LogFrom{Primary: "deployed_version/refresh", Secondary: *serviceID}
 

service/deployed_version/types.go

@@ -18,14 +18,15 @@ package deployedver
 import (
 	"encoding/json"
 	"fmt"
+	"net/http"
 
 	opt "github.com/release-argus/Argus/service/option"
 	"github.com/release-argus/Argus/service/status"
 	"github.com/release-argus/Argus/util"
 )
 
 var (
-	supportedTypes = []string{"GET", "POST"}
+	supportedTypes = []string{http.MethodGet, http.MethodPost}
 )
 
 // Base is the base struct for the Lookup struct.

service/deployed_version/verify.go

@@ -18,6 +18,7 @@ package deployedver
 import (
 	"errors"
 	"fmt"
+	"net/http"
 	"regexp"
 	"strings"
 
@@ -34,14 +35,14 @@ func (l *Lookup) CheckValues(prefix string) error {
 	// Method
 	l.Method = strings.ToUpper(l.Method)
 	if l.Method == "" {
-		l.Method = "GET"
+		l.Method = http.MethodGet
 	} else if !util.Contains(supportedTypes, l.Method) {
 		errs = append(errs,
 			fmt.Errorf("%smethod: %q <invalid> (only [%s] are allowed)",
 				prefix, l.Method, strings.Join(supportedTypes, ", ")))
 	}
 	// Body unused in GET, ensure it is empty.
-	if l.Method == "GET" {
+	if l.Method == http.MethodGet {
 		l.Body = ""
 	}
 

service/deployed_version/verify_test.go

@@ -17,6 +17,7 @@
 package deployedver
 
 import (
+	"net/http"
 	"strings"
 	"testing"
 
@@ -40,7 +41,7 @@ func TestLookup_CheckValues(t *testing.T) {
 		},
 		"valid service": {
 			errRegex: `^$`,
-			method:   "GET",
+			method:   http.MethodGet,
 			url:      "https://example.com",
 			regex:    `[0-9.]+`,
 			defaults: &Defaults{},
@@ -57,7 +58,7 @@ func TestLookup_CheckValues(t *testing.T) {
 		},
 		"method - valid": {
 			errRegex: `^$`,
-			method:   "GET",
+			method:   http.MethodGet,
 			url:      "https://example.com",
 		},
 		"method - case insensitive": {
@@ -67,53 +68,53 @@ func TestLookup_CheckValues(t *testing.T) {
 		},
 		"url - empty string": {
 			errRegex: `url: <required>`,
-			method:   "GET",
+			method:   http.MethodGet,
 			url:      "",
 			defaults: &Defaults{},
 		},
 		"body - removed for GET": {
 			errRegex: `^$`,
-			method:   "GET",
+			method:   http.MethodGet,
 			url:      "https://example.com",
 			body:     "foo",
 			defaults: &Defaults{},
 		},
 		"body - not removed for POST": {
 			errRegex: `^$`,
-			method:   "POST",
+			method:   http.MethodPost,
 			url:      "https://example.com",
 			body:     "foo",
 			defaults: &Defaults{},
 		},
 		"json - invalid, string in square brackets": {
 			errRegex: `json: .* <invalid>`,
-			method:   "GET",
+			method:   http.MethodGet,
 			json:     "foo[bar]",
 			defaults: &Defaults{},
 		},
 		"regex - invalid": {
 			errRegex: `regex: .* <invalid>`,
-			method:   "GET",
+			method:   http.MethodGet,
 			regex:    `[0-`,
 			defaults: &Defaults{},
 		},
 		"regexTemplate - with no regex": {
-			method:        "GET",
+			method:        http.MethodGet,
 			url:           "https://example.com",
 			errRegex:      `^$`,
 			regexTemplate: "$1.$2.$3",
 			defaults:      &Defaults{},
 		},
 		"all errs": {
 			errRegex: `url: <required>`,
-			method:   "GET",
+			method:   http.MethodGet,
 			url:      "",
 			regex:    `[0-`,
 			defaults: &Defaults{},
 		},
 		"no url doesn't fail for Lookup Defaults": {
 			errRegex: `^$`,
-			method:   "GET",
+			method:   http.MethodGet,
 			url:      "",
 			defaults: nil,
 		},
@@ -159,17 +160,17 @@ func TestLookup_CheckValues(t *testing.T) {
 				t.Fatalf("RegexTemplate should be nil when Regex is empty")
 			}
 			// AND Body is empty when Method is GET
-			if lookup.Method == "GET" && lookup.Body != "" {
+			if lookup.Method == http.MethodGet && lookup.Body != "" {
 				t.Fatalf("Body should be nil when Method is GET")
 			}
 			// AND Body is kept when Method is POST
-			if lookup.Method == "POST" && hadBody != "" && lookup.Body == "" {
+			if lookup.Method == http.MethodPost && hadBody != "" && lookup.Body == "" {
 				t.Fatalf("Body should be kept when Method is POST")
 			}
 			// AND Method is uppercased
 			wantMethod := strings.ToUpper(tc.method)
 			if wantMethod == "" {
-				wantMethod = "GET"
+				wantMethod = http.MethodGet
 			}
 			if lookup.Method != wantMethod {
 				t.Fatalf("Method should be uppercased:\nwant: %q\ngot:  %q",

service/init.go

@@ -141,7 +141,6 @@ func (s *Service) Init(
 		&s.Options,
 		&s.Status,
 		&s.Defaults.DeployedVersionLookup, &s.HardDefaults.DeployedVersionLookup)
-
 }
 
 // initMetrics will initialise the Prometheus metrics for the Service.

service/latest_version/filter/docker.go

@@ -295,7 +295,7 @@ func (d *DockerCheck) CheckValues(prefix string) error {
 			prefix, d.Image))
 		// e.g. prometheus = library/prometheus on the docker hub api.
 	case d.Type == "hub" && strings.Count(d.Image, "/") == 0:
-		d.Image = fmt.Sprintf("library/%s", d.Image)
+		d.Image = "library/" + d.Image
 	}
 
 	// Tag
@@ -307,7 +307,7 @@ func (d *DockerCheck) CheckValues(prefix string) error {
 		errs = append(errs, fmt.Errorf("%stag: %q <invalid> (didn't pass templating)",
 			prefix, d.Tag))
 	default:
-		if _, err := net_url.Parse(fmt.Sprintf("https://example.com/%s", d.Tag)); err != nil {
+		if _, err := net_url.Parse("https://example.com/" + d.Tag); err != nil {
 			errs = append(errs, fmt.Errorf("%stag: %q <invalid> (invalid for URL formatting)",
 				prefix, d.Tag))
 		}
@@ -339,7 +339,7 @@ func (d *DockerCheck) checkToken() error {
 			return fmt.Errorf("token: <required> (token for %s)",
 				username)
 		} else if username == "" && token != "" {
-			return fmt.Errorf("username: <required> (token is for who?)")
+			return errors.New("username: <required> (token is for who?)")
 		}
 	case "quay", "ghcr":
 		// Token not required.
@@ -392,7 +392,7 @@ func (d *DockerCheck) getToken() string {
 	return util.EvalEnvVars(d.Defaults.getToken(d.GetType()))
 }
 
-// getToken returns the token as is,
+// getToken returns the token as is.
 func (d *DockerCheckDefaults) getToken(dType string) string {
 	if d == nil {
 		return ""

service/latest_version/refresh.go

@@ -17,6 +17,7 @@ package latestver
 
 import (
 	"encoding/json"
+	"errors"
 	"fmt"
 	"strings"
 
@@ -33,7 +34,7 @@ func Refresh(
 	semanticVersioning *string, // nil, "true", "false", "null" (unchanged, true, false, default).
 ) (string, bool, error) {
 	if lookup == nil {
-		return "", false, fmt.Errorf("lookup is nil")
+		return "", false, errors.New("lookup is nil")
 	}
 
 	logFrom := logutil.LogFrom{Primary: "latest_version/refresh", Secondary: *lookup.GetStatus().ServiceID}

service/latest_version/types/github/gets.go

@@ -70,7 +70,7 @@ func (l *Lookup) ServiceURL(ignoreWebURL bool) (serviceURL string) {
 	// GitHub service. Get the non-API URL.
 	// If "owner/repo" rather than a full path.
 	if strings.Count(serviceURL, "/") == 1 {
-		serviceURL = fmt.Sprintf("https://github.com/%s", serviceURL)
+		serviceURL = "https://github.com/" + serviceURL
 	}
 	return
 }

service/latest_version/types/github/query.go

@@ -117,7 +117,7 @@ func (l *Lookup) createRequest(logFrom logutil.LogFrom) (*http.Request, error) {
 	req.Header.Set("Connection", "close")
 	// Access Token.
 	if accessToken := l.accessToken(); accessToken != "" {
-		req.Header.Set("Authorization", fmt.Sprintf("token %s", accessToken))
+		req.Header.Set("Authorization", "token "+accessToken)
 	}
 	// Conditional requests - https://docs.github.com/en/rest/overview/resources-in-the-rest-api#conditional-requests.
 	if eTag := l.data.ETag(); eTag != "" {

service/latest_version/types/github/query_test.go

@@ -398,7 +398,7 @@ func TestGetResponse_ReadError(t *testing.T) {
 	t.Cleanup(func() { server.Close() })
 
 	// AND a request to the mock server's URL.
-	req, err := http.NewRequest("GET", server.URL, nil)
+	req, err := http.NewRequest(http.MethodGet, server.URL, nil)
 	if err != nil {
 		t.Fatalf("github.Lookup.getResponse() could not create request: %v", err)
 	}

service/latest_version/types/web/query.go

@@ -103,7 +103,7 @@ func (l *Lookup) httpRequest(logFrom logutil.LogFrom) ([]byte, error) {
 	if err != nil {
 		// Don't crash on invalid certs.
 		if strings.Contains(err.Error(), "x509") {
-			err = fmt.Errorf("x509 (certificate invalid)")
+			err = errors.New("x509 (certificate invalid)")
 			logutil.Log.Warn(err, logFrom, true)
 			return nil, err
 		}

service/new.go

@@ -99,7 +99,7 @@ func FromPayload(
 		if err != nil {
 			logutil.Log.Error(err, logFrom, true)
 			logutil.Log.Verbose(
-				fmt.Sprintf("Payload: %s", buf.String()),
+				"Payload: "+buf.String(),
 				logFrom, true)
 			return nil, err //nolint:wrapcheck
 		}