Replace uses of fmt.Sprintf and fmt.Errorf with better alternatives

.golangci.yml

@@ -19,6 +19,7 @@ linters:
     - govet                     # Vet examines Go source code and reports suspicious constructs, such as Printf calls whose arguments do not align with the format string
     - ineffassign               # Detects when assignments to existing variables are not used
     - misspell                  # Finds commonly misspelled English words in comments
+    - perfsprint                # replace uses of fmt.Sprintf and fmt.Errorf with better (both in CPU and memory) alternatives
     - pkgconfigusage            # Linter for checking usage of pkgconfig inside components folder
     - revive                    # Revive is a replacement for golint, a coding style checker
     - staticcheck               # staticcheck is a go vet on steroids, applying a ton of static analysis checks

cmd/agent/common/import.go

@@ -8,6 +8,7 @@
 package common
 
 import (
+	"errors"
 	"fmt"
 	"os"
 	"os/user"
@@ -230,7 +231,7 @@ func copyFile(src, dst string, overwrite bool, transformations []TransformationF
 				return fmt.Errorf("unable to create a backup copy of the destination file: %v", err)
 			}
 		} else {
-			return fmt.Errorf("destination file already exists, run the command again with --force or -f to overwrite it")
+			return errors.New("destination file already exists, run the command again with --force or -f to overwrite it")
 		}
 	}
 

cmd/agent/subcommands/analyzelogs/command.go

@@ -9,6 +9,7 @@ package analyzelogs
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"os"
 	"time"
@@ -72,7 +73,7 @@ func Commands(globalParams *command.GlobalParams) []*cobra.Command {
 		Long:  `Run a Datadog agent logs configuration and print the results to stdout`,
 		RunE: func(_ *cobra.Command, args []string) error {
 			if len(args) < 1 {
-				return fmt.Errorf("log config file path is required")
+				return errors.New("log config file path is required")
 			}
 			cliParams.LogConfigPath = args[0]
 			return fxutil.OneShot(runAnalyzeLogs,
@@ -214,5 +215,5 @@ func resolveCheckConfig(ac autodiscovery.Component, cliParams *CliParams) ([]*so
 		}
 		return sources, nil
 	}
-	return nil, fmt.Errorf("Cannot get source")
+	return nil, errors.New("Cannot get source")
 }

cmd/agent/subcommands/dogstatsdcapture/command.go

@@ -85,7 +85,7 @@ func dogstatsdCapture(_ log.Component, config config.Component, cliParams *cliPa
 	defer cancel()
 
 	md := metadata.MD{
-		"authorization": []string{fmt.Sprintf("Bearer %s", ipc.GetAuthToken())}, // TODO IPC: replace with GRPC Client
+		"authorization": []string{"Bearer " + ipc.GetAuthToken()}, // TODO IPC: replace with GRPC Client
 	}
 	ctx = metadata.NewOutgoingContext(ctx, md)
 

cmd/agent/subcommands/dogstatsdreplay/command.go

@@ -8,6 +8,7 @@ package dogstatsdreplay
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"net"
 	"os"
@@ -95,7 +96,7 @@ func dogstatsdReplay(_ log.Component, config config.Component, cliParams *cliPar
 	fmt.Printf("Replaying dogstatsd traffic...\n\n")
 
 	md := metadata.MD{
-		"authorization": []string{fmt.Sprintf("Bearer %s", ipc.GetAuthToken())},
+		"authorization": []string{"Bearer " + ipc.GetAuthToken()},
 	}
 	ctx = metadata.NewOutgoingContext(ctx, md)
 
@@ -123,7 +124,7 @@ func dogstatsdReplay(_ log.Component, config config.Component, cliParams *cliPar
 
 	s := pkgconfigsetup.Datadog().GetString("dogstatsd_socket")
 	if s == "" {
-		return fmt.Errorf("Dogstatsd UNIX socket disabled")
+		return errors.New("Dogstatsd UNIX socket disabled")
 	}
 
 	addr, err := net.ResolveUnixAddr("unixgram", s)

cmd/agent/subcommands/import/command.go

@@ -7,6 +7,7 @@
 package cmdimport
 
 import (
+	"errors"
 	"fmt"
 	"os"
 
@@ -56,7 +57,7 @@ func Commands(globalParams *command.GlobalParams) []*cobra.Command {
 
 func importCmd(cliParams *cliParams) error {
 	if len(cliParams.args) != 2 {
-		return fmt.Errorf("please provide all the required arguments")
+		return errors.New("please provide all the required arguments")
 	}
 
 	if cliParams.ConfFilePath != "" {

cmd/agent/subcommands/integrations/command.go

@@ -131,7 +131,7 @@ You must specify a version of the package to install using the syntax: <package>
 		},
 	}
 	installCmd.Flags().BoolVarP(
-		&cliParams.localWheel, "local-wheel", "w", false, fmt.Sprintf("install an agent check from a locally available wheel file. %s", disclaimer),
+		&cliParams.localWheel, "local-wheel", "w", false, "install an agent check from a locally available wheel file. "+disclaimer,
 	)
 	installCmd.Flags().BoolVarP(
 		&cliParams.thirdParty, "third-party", "t", false, "install a community or vendor-contributed integration",
@@ -288,9 +288,9 @@ func getCommandPython(useSysPython bool) (string, error) {
 
 func validateArgs(args []string, local bool) error {
 	if len(args) > 1 {
-		return fmt.Errorf("Too many arguments")
+		return errors.New("Too many arguments")
 	} else if len(args) == 0 {
-		return fmt.Errorf("Missing package argument")
+		return errors.New("Missing package argument")
 	}
 
 	if !local {
@@ -323,7 +323,7 @@ func pip(cliParams *cliParams, args []string, stdout io.Writer, stderr io.Writer
 	args = append([]string{"-mpip"}, cmd)
 
 	if cliParams.verbose > 0 {
-		args = append(args, fmt.Sprintf("-%s", strings.Repeat("v", cliParams.verbose)))
+		args = append(args, "-"+strings.Repeat("v", cliParams.verbose))
 	}
 
 	// Append implicit flags to the *pip* command
@@ -420,22 +420,20 @@ func install(cliParams *cliParams, _ log.Component) error {
 			return fmt.Errorf("Some errors prevented moving %s configuration files: %v", integration, err)
 		}
 
-		fmt.Println(color.GreenString(fmt.Sprintf(
-			"Successfully completed the installation of %s", integration,
-		)))
+		fmt.Println(color.GreenString("Successfully completed the installation of " + integration))
 
 		return nil
 	}
 
 	// Additional verification for installation
 	if len(strings.Split(cliParams.args[0], "==")) != 2 {
-		return fmt.Errorf("you must specify a version to install with <package>==<version>")
+		return errors.New("you must specify a version to install with <package>==<version>")
 	}
 
 	intVer := strings.Split(cliParams.args[0], "==")
 	integration := normalizePackageName(strings.TrimSpace(intVer[0]))
 	if integration == "datadog-checks-base" {
-		return fmt.Errorf("this command does not allow installing datadog-checks-base")
+		return errors.New("this command does not allow installing datadog-checks-base")
 	}
 	versionToInstall, err := semver.NewVersion(strings.TrimSpace(intVer[1]))
 	if err != nil || versionToInstall == nil {
@@ -517,7 +515,7 @@ func downloadWheel(cliParams *cliParams, integration, version, rootLayoutType st
 		"--type", rootLayoutType,
 	}
 	if cliParams.verbose > 0 {
-		args = append(args, fmt.Sprintf("-%s", strings.Repeat("v", cliParams.verbose)))
+		args = append(args, "-"+strings.Repeat("v", cliParams.verbose))
 	}
 
 	if cliParams.unsafeDisableVerification {
@@ -554,9 +552,9 @@ func downloadWheel(cliParams *cliParams, integration, version, rootLayoutType st
 	proxies := pkgconfigsetup.Datadog().GetProxies()
 	if proxies != nil {
 		downloaderCmd.Env = append(downloaderCmd.Env,
-			fmt.Sprintf("HTTP_PROXY=%s", proxies.HTTP),
-			fmt.Sprintf("HTTPS_PROXY=%s", proxies.HTTPS),
-			fmt.Sprintf("NO_PROXY=%s", strings.Join(proxies.NoProxy, ",")),
+			"HTTP_PROXY="+proxies.HTTP,
+			"HTTPS_PROXY="+proxies.HTTPS,
+			"NO_PROXY="+strings.Join(proxies.NoProxy, ","),
 		)
 	}
 
@@ -790,7 +788,7 @@ func getVersionFromReqLine(integration string, lines string) (*semver.Version, b
 func moveConfigurationFilesOf(cliParams *cliParams, integration string) error {
 	confFolder := pkgconfigsetup.Datadog().GetString("confd_path")
 	check := getIntegrationName(integration)
-	confFileDest := filepath.Join(confFolder, fmt.Sprintf("%s.d", check))
+	confFileDest := filepath.Join(confFolder, check+".d")
 	if err := os.MkdirAll(confFileDest, os.ModeDir|0755); err != nil {
 		return err
 	}
@@ -845,9 +843,7 @@ func moveConfigurationFiles(srcFolder string, dstFolder string) error {
 			errorMsg = fmt.Sprintf("%s\nError writing configuration file %s: %v", errorMsg, dst, err)
 			continue
 		}
-		fmt.Println(color.GreenString(fmt.Sprintf(
-			"Successfully copied configuration file %s", filename,
-		)))
+		fmt.Println(color.GreenString("Successfully copied configuration file " + filename))
 	}
 	if errorMsg != "" {
 		return errors.New(errorMsg)

cmd/agent/subcommands/integrations/integrations_darwin.go

@@ -8,13 +8,13 @@
 package integrations
 
 import (
-	"fmt"
+	"errors"
 	"os"
 )
 
 func validateUser(_ bool) error {
 	if os.Geteuid() != 0 {
-		return fmt.Errorf("please run this tool with the root user")
+		return errors.New("please run this tool with the root user")
 	}
 	return nil
 }

cmd/agent/subcommands/integrations/integrations_nix.go

@@ -8,13 +8,13 @@
 package integrations
 
 import (
-	"fmt"
+	"errors"
 	"os"
 )
 
 func validateUser(allowRoot bool) error {
 	if os.Geteuid() == 0 && !allowRoot {
-		return fmt.Errorf("operation is disabled for root user. Please run this tool with the agent-running user or add '--allow-root/-r' to force")
+		return errors.New("operation is disabled for root user. Please run this tool with the agent-running user or add '--allow-root/-r' to force")
 	}
 	return nil
 }

cmd/agent/subcommands/integrations/integrations_nix_helpers.go

@@ -24,7 +24,7 @@ var (
 )
 
 func getRelPyPath() string {
-	return filepath.Join("embedded", "bin", fmt.Sprintf("%s3", pythonBin))
+	return filepath.Join("embedded", "bin", pythonBin+"3")
 }
 
 func getRelChecksPath(cliParams *cliParams) (string, error) {

cmd/agent/subcommands/launchgui/command.go

@@ -7,6 +7,7 @@
 package launchgui
 
 import (
+	"errors"
 	"fmt"
 	"net"
 
@@ -56,7 +57,7 @@ func Commands(globalParams *command.GlobalParams) []*cobra.Command {
 func launchGui(config config.Component, _ *cliParams, _ log.Component, client ipc.HTTPClient) error {
 	guiPort := config.GetString("GUI_port")
 	if guiPort == "-1" {
-		return fmt.Errorf("GUI not enabled: to enable, please set an appropriate port in your datadog.yaml file")
+		return errors.New("GUI not enabled: to enable, please set an appropriate port in your datadog.yaml file")
 	}
 
 	// 'http://localhost' is preferred over 'http://127.0.0.1' due to Internet Explorer behavior.

cmd/agent/subcommands/remoteconfig/command.go

@@ -94,7 +94,7 @@ func reset(_ *cliParams, config config.Component, ipc ipc.Component) error {
 	ctx, closeFn := context.WithCancel(context.Background())
 	defer closeFn()
 	md := metadata.MD{
-		"authorization": []string{fmt.Sprintf("Bearer %s", ipc.GetAuthToken())},
+		"authorization": []string{"Bearer " + ipc.GetAuthToken()},
 	}
 	ctx = metadata.NewOutgoingContext(ctx, md)
 
@@ -126,7 +126,7 @@ func state(_ *cliParams, config config.Component, ipc ipc.Component) error {
 	ctx, closeFn := context.WithCancel(context.Background())
 	defer closeFn()
 	md := metadata.MD{
-		"authorization": []string{fmt.Sprintf("Bearer %s", ipc.GetAuthToken())}, // TODO IPC: use GRPC client
+		"authorization": []string{"Bearer " + ipc.GetAuthToken()}, // TODO IPC: use GRPC client
 	}
 	ctx = metadata.NewOutgoingContext(ctx, md)
 

cmd/agent/subcommands/run/command.go

@@ -8,8 +8,8 @@ package run
 
 import (
 	"context"
+	"errors"
 	_ "expvar" // Blank import used because this isn't directly used in this file
-	"fmt"
 	"net/http"
 	_ "net/http/pprof" // Blank import used because this isn't directly used in this file
 	"os"
@@ -321,7 +321,7 @@ func run(log log.Component,
 			stopCh <- nil
 		case <-signals.ErrorStopper:
 			_ = log.Critical("The Agent has encountered an error, shutting down...")
-			stopCh <- fmt.Errorf("shutting down because of an error")
+			stopCh <- errors.New("shutting down because of an error")
 		case sig := <-signalCh:
 			log.Infof("Received signal '%s', shutting down...", sig)
 			stopCh <- nil

cmd/agent/subcommands/status/command.go

@@ -192,7 +192,7 @@ func requestStatus(cliParams *cliParams, client ipc.HTTPClient) error {
 
 func componentStatusCmd(_ log.Component, cliParams *cliParams, client ipc.HTTPClient) error {
 	if len(cliParams.args) > 1 {
-		return fmt.Errorf("only one section must be specified")
+		return errors.New("only one section must be specified")
 	}
 
 	return redactError(componentStatus(cliParams, cliParams.args[0], client))

cmd/agent/subcommands/streamlogs/command.go

@@ -10,6 +10,7 @@ import (
 	"bufio"
 	"bytes"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -79,7 +80,7 @@ func Commands(globalParams *command.GlobalParams) []*cobra.Command {
 	// PreRunE is used to validate duration before stream-logs is run.
 	cmd.PreRunE = func(_ *cobra.Command, _ []string) error {
 		if cliParams.Duration < 0 {
-			return fmt.Errorf("duration must be a positive value")
+			return errors.New("duration must be a positive value")
 		}
 		return nil
 	}

cmd/cluster-agent-cloudfoundry/command/command.go

@@ -9,7 +9,6 @@
 package command
 
 import (
-	"fmt"
 	"os"
 
 	"github.com/fatih/color"
@@ -47,7 +46,7 @@ func MakeCommand(subcommandFactories []SubcommandFactory) *cobra.Command {
 
 	// AgentCmd is the root command
 	agentCmd := &cobra.Command{
-		Use:   fmt.Sprintf("%s [command]", os.Args[0]),
+		Use:   os.Args[0] + " [command]",
 		Short: "Datadog Cluster Agent for Cloud Foundry at your service.",
 		Long: `
 Datadog Cluster Agent for Cloud Foundry takes care of running checks that need to run only

cmd/cluster-agent-cloudfoundry/subcommands/run/command.go

@@ -10,6 +10,7 @@ package run
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"os/signal"
@@ -202,7 +203,7 @@ func run(
 	}
 	pkglog.Infof("Hostname is: %s", hname)
 
-	demultiplexer.AddAgentStartupTelemetry(fmt.Sprintf("%s - Datadog Cluster Agent", version.AgentVersion))
+	demultiplexer.AddAgentStartupTelemetry(version.AgentVersion + " - Datadog Cluster Agent")
 
 	pkglog.Infof("Datadog Cluster Agent is now running.")
 
@@ -338,7 +339,7 @@ func initializeBBSCache(ctx context.Context) error {
 			}
 		case <-timer.C:
 			ticker.Stop()
-			return fmt.Errorf("BBS Cache failed to warm up. Misconfiguration error? Inspect logs")
+			return errors.New("BBS Cache failed to warm up. Misconfiguration error? Inspect logs")
 		}
 	}
 }

cmd/cluster-agent/api/server_test.go

@@ -66,7 +66,7 @@ func TestValidateTokenMiddleware(t *testing.T) {
 			req, err := http.NewRequest("GET", tt.path, nil)
 			require.NoError(t, err)
 
-			req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", tt.authToken))
+			req.Header.Add("Authorization", "Bearer "+tt.authToken)
 
 			rr := httptest.NewRecorder()
 

cmd/cluster-agent/api/v1/kubernetes_metadata_test.go

@@ -67,7 +67,7 @@ func TestGetNodeAnnotations(t *testing.T) {
 	}{
 		{
 			name:    "no filters passed only host aliases annotations returned",
-			path:    fmt.Sprintf("/annotations/node/%s", testNode),
+			path:    "/annotations/node/" + testNode,
 			muxVars: map[string]string{"nodeName": testNode},
 			body:    map[string]string{"annotation1": "abc"}, // hardcoded above in workloadmeta mock
 			status:  http.StatusOK,
@@ -168,7 +168,7 @@ func TestGetNodeUID(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			req, _ := http.NewRequest("GET", fmt.Sprintf("/uid/node/%s", tt.node), nil)
+			req, _ := http.NewRequest("GET", "/uid/node/"+tt.node, nil)
 			req = mux.SetURLVars(req, map[string]string{"nodeName": tt.node})
 
 			respw := httptest.NewRecorder()