TUN-8914: Create a flags module to group all cloudflared cli flags

## Summary

This commit refactors some of the flags of cloudflared to their own module, so that they can be used across the code without requiring to literal strings which are much more error prone.

 Closes TUN-8914

Author: jcsf

cmd/cloudflared/access/cmd.go

@@ -19,6 +19,7 @@ import (
 
 	"github.com/cloudflare/cloudflared/carrier"
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/cliutil"
+	cfdflags "github.com/cloudflare/cloudflared/cmd/cloudflared/flags"
 	"github.com/cloudflare/cloudflared/logger"
 	"github.com/cloudflare/cloudflared/sshgen"
 	"github.com/cloudflare/cloudflared/token"
@@ -172,15 +173,15 @@ func Commands() []*cli.Command {
 							EnvVars: []string{"TUNNEL_SERVICE_TOKEN_SECRET"},
 						},
 						&cli.StringFlag{
-							Name:  logger.LogFileFlag,
+							Name:  cfdflags.LogFile,
 							Usage: "Save application log to this file for reporting issues.",
 						},
 						&cli.StringFlag{
-							Name:  logger.LogSSHDirectoryFlag,
+							Name:  cfdflags.LogDirectory,
 							Usage: "Save application log to this directory for reporting issues.",
 						},
 						&cli.StringFlag{
-							Name:    logger.LogSSHLevelFlag,
+							Name:    cfdflags.LogLevelSSH,
 							Aliases: []string{"loglevel"}, //added to match the tunnel side
 							Usage:   "Application logging level {debug, info, warn, error, fatal}. ",
 						},
@@ -342,15 +343,15 @@ func run(cmd string, args ...string) error {
 		return err
 	}
 	go func() {
-		io.Copy(os.Stderr, stderr)
+		_, _ = io.Copy(os.Stderr, stderr)
 	}()
 
 	stdout, err := c.StdoutPipe()
 	if err != nil {
 		return err
 	}
 	go func() {
-		io.Copy(os.Stdout, stdout)
+		_, _ = io.Copy(os.Stdout, stdout)
 	}()
 	return c.Run()
 }
@@ -531,7 +532,7 @@ func isFileThere(candidate string) bool {
 }
 
 // verifyTokenAtEdge checks for a token on disk, or generates a new one.
-// Then makes a request to to the origin with the token to ensure it is valid.
+// Then makes a request to the origin with the token to ensure it is valid.
 // Returns nil if token is valid.
 func verifyTokenAtEdge(appUrl *url.URL, appInfo *token.AppInfo, c *cli.Context, log *zerolog.Logger) error {
 	headers := parseRequestHeaders(c.StringSlice(sshHeaderFlag))

cmd/cloudflared/cliutil/logger.go

@@ -4,7 +4,7 @@ import (
 	"github.com/urfave/cli/v2"
 	"github.com/urfave/cli/v2/altsrc"
 
-	"github.com/cloudflare/cloudflared/logger"
+	cfdflags "github.com/cloudflare/cloudflared/cmd/cloudflared/flags"
 )
 
 var (
@@ -15,34 +15,34 @@ var (
 func ConfigureLoggingFlags(shouldHide bool) []cli.Flag {
 	return []cli.Flag{
 		altsrc.NewStringFlag(&cli.StringFlag{
-			Name:    logger.LogLevelFlag,
+			Name:    cfdflags.LogLevel,
 			Value:   "info",
 			Usage:   "Application logging level {debug, info, warn, error, fatal}. " + debugLevelWarning,
 			EnvVars: []string{"TUNNEL_LOGLEVEL"},
 			Hidden:  shouldHide,
 		}),
 		altsrc.NewStringFlag(&cli.StringFlag{
-			Name:    logger.LogTransportLevelFlag,
+			Name:    cfdflags.TransportLogLevel,
 			Aliases: []string{"proto-loglevel"}, // This flag used to be called proto-loglevel
 			Value:   "info",
 			Usage:   "Transport logging level(previously called protocol logging level) {debug, info, warn, error, fatal}",
 			EnvVars: []string{"TUNNEL_PROTO_LOGLEVEL", "TUNNEL_TRANSPORT_LOGLEVEL"},
 			Hidden:  shouldHide,
 		}),
 		altsrc.NewStringFlag(&cli.StringFlag{
-			Name:    logger.LogFileFlag,
+			Name:    cfdflags.LogFile,
 			Usage:   "Save application log to this file for reporting issues.",
 			EnvVars: []string{"TUNNEL_LOGFILE"},
 			Hidden:  shouldHide,
 		}),
 		altsrc.NewStringFlag(&cli.StringFlag{
-			Name:    logger.LogDirectoryFlag,
+			Name:    cfdflags.LogDirectory,
 			Usage:   "Save application log to this directory for reporting issues.",
 			EnvVars: []string{"TUNNEL_LOGDIRECTORY"},
 			Hidden:  shouldHide,
 		}),
 		altsrc.NewStringFlag(&cli.StringFlag{
-			Name:    "trace-output",
+			Name:    cfdflags.TraceOutput,
 			Usage:   "Name of trace output file, generated when cloudflared stops.",
 			EnvVars: []string{"TUNNEL_TRACE_OUTPUT"},
 			Hidden:  shouldHide,

cmd/cloudflared/flags/flags.go

@@ -0,0 +1,152 @@
+package flags
+
+const (
+	// HaConnections specifies how many connections to make to the edge
+	HaConnections = "ha-connections"
+
+	// SshPort is the port on localhost the cloudflared ssh server will run on
+	SshPort = "local-ssh-port"
+
+	// SshIdleTimeout defines the duration a SSH session can remain idle before being closed
+	SshIdleTimeout = "ssh-idle-timeout"
+
+	// SshMaxTimeout defines the max duration a SSH session can remain open for
+	SshMaxTimeout = "ssh-max-timeout"
+
+	// SshLogUploaderBucketName is the bucket name to use for the SSH log uploader
+	SshLogUploaderBucketName = "bucket-name"
+
+	// SshLogUploaderRegionName is the AWS region name to use for the SSH log uploader
+	SshLogUploaderRegionName = "region-name"
+
+	// SshLogUploaderSecretID is the Secret id of SSH log uploader
+	SshLogUploaderSecretID = "secret-id"
+
+	// SshLogUploaderAccessKeyID is the Access key id of SSH log uploader
+	SshLogUploaderAccessKeyID = "access-key-id"
+
+	// SshLogUploaderSessionTokenID is the Session token of SSH log uploader
+	SshLogUploaderSessionTokenID = "session-token"
+
+	// SshLogUploaderS3URL is the S3 URL of SSH log uploader (e.g. don't use AWS s3 and use google storage bucket instead)
+	SshLogUploaderS3URL = "s3-url-host"
+
+	// HostKeyPath is the path of the dir to save SSH host keys too
+	HostKeyPath = "host-key-path"
+
+	// RpcTimeout is how long to wait for a Capnp RPC request to the edge
+	RpcTimeout = "rpc-timeout"
+
+	// WriteStreamTimeout sets if we should have a timeout when writing data to a stream towards the destination (edge/origin).
+	WriteStreamTimeout = "write-stream-timeout"
+
+	// QuicDisablePathMTUDiscovery sets if QUIC should not perform PTMU discovery and use a smaller (safe) packet size.
+	// Packets will then be at most 1252 (IPv4) / 1232 (IPv6) bytes in size.
+	// Note that this may result in packet drops for UDP proxying, since we expect being able to send at least 1280 bytes of inner packets.
+	QuicDisablePathMTUDiscovery = "quic-disable-pmtu-discovery"
+
+	// QuicConnLevelFlowControlLimit controls the max flow control limit allocated for a QUIC connection. This controls how much data is the
+	// receiver willing to buffer. Once the limit is reached, the sender will send a DATA_BLOCKED frame to indicate it has more data to write,
+	// but it's blocked by flow control
+	QuicConnLevelFlowControlLimit = "quic-connection-level-flow-control-limit"
+
+	// QuicStreamLevelFlowControlLimit is similar to quicConnLevelFlowControlLimit but for each QUIC stream. When the sender is blocked,
+	// it will send a STREAM_DATA_BLOCKED frame
+	QuicStreamLevelFlowControlLimit = "quic-stream-level-flow-control-limit"
+
+	// Ui is to enable launching cloudflared in interactive UI mode
+	Ui = "ui"
+
+	// ConnectorLabel is the command line flag to give a meaningful label to a specific connector
+	ConnectorLabel = "label"
+
+	// MaxActiveFlows is the command line flag to set the maximum number of flows that cloudflared can be processing at the same time
+	MaxActiveFlows = "max-active-flows"
+
+	// Tag is the command line flag to set custom tags used to identify this tunnel via added HTTP request headers to the origin
+	Tag = "tag"
+
+	// Protocol is the command line flag to set the protocol to use to connect to the Cloudflare Edge
+	Protocol = "protocol"
+
+	// PostQuantum is the command line flag to force the connection to Cloudflare Edge to use Post Quantum cryptography
+	PostQuantum = "post-quantum"
+
+	// Features is the command line flag to opt into various features that are still being developed or tested
+	Features = "features"
+
+	// EdgeIpVersion is the command line flag to set the Cloudflare Edge IP address version to connect with
+	EdgeIpVersion = "edge-ip-version"
+
+	// EdgeBindAddress is the command line flag to bind to IP address for outgoing connections to Cloudflare Edge
+	EdgeBindAddress = "edge-bind-address"
+
+	// Force is the command line flag to specify if you wish to force an action
+	Force = "force"
+
+	// Edge is the command line flag to set the address of the Cloudflare tunnel server. Only works in Cloudflare's internal testing environment
+	Edge = "edge"
+
+	// Region is the command line flag to set the Cloudflare Edge region to connect to
+	Region = "region"
+
+	// IsAutoUpdated is the command line flag to signal the new process that cloudflared has been autoupdated
+	IsAutoUpdated = "is-autoupdated"
+
+	// LBPool is the command line flag to set the name of the load balancing pool to add this origin to
+	LBPool = "lb-pool"
+
+	// Retries is the command line flag to set the maximum number of retries for connection/protocol errors
+	Retries = "retries"
+
+	// MaxEdgeAddrRetries is the command line flag to set the maximum number of times to retry on edge addrs before falling back to a lower protocol
+	MaxEdgeAddrRetries = "max-edge-addr-retries"
+
+	// GracePeriod is the command line flag to set the maximum amount of time that cloudflared waits to shut down if it is still serving requests
+	GracePeriod = "grace-period"
+
+	// ICMPV4Src is the command line flag to set the source address and the interface name to send/receive ICMPv4 messages
+	ICMPV4Src = "icmpv4-src"
+
+	// ICMPV6Src is the command line flag to set the source address and the interface name to send/receive ICMPv6 messages
+	ICMPV6Src = "icmpv6-src"
+
+	// ProxyDns is the command line flag to run DNS server over HTTPS
+	ProxyDns = "proxy-dns"
+
+	// Name is the command line to set the name of the tunnel
+	Name = "name"
+
+	// AutoUpdateFreq is the command line for setting the frequency that cloudflared checks for updates
+	AutoUpdateFreq = "autoupdate-freq"
+
+	// NoAutoUpdate is the command line flag to disable cloudflared from checking for updates
+	NoAutoUpdate = "no-autoupdate"
+
+	// LogLevel is the command line flag for the cloudflared logging level
+	LogLevel = "loglevel"
+
+	// LogLevelSSH is the command line flag for the cloudflared ssh logging level
+	LogLevelSSH = "log-level"
+
+	// TransportLogLevel is the command line flag for the transport logging level
+	TransportLogLevel = "transport-loglevel"
+
+	// LogFile is the command line flag to define the file where application logs will be stored
+	LogFile = "logfile"
+
+	// LogDirectory is the command line flag to define the directory where application logs will be stored.
+	LogDirectory = "log-directory"
+
+	// TraceOutput is the command line flag to set the name of trace output file
+	TraceOutput = "trace-output"
+
+	// OriginCert is the command line flag to define the path for the origin certificate used by cloudflared
+	OriginCert = "origincert"
+
+	// Metrics is the command line flag to define the address of the metrics server
+	Metrics = "metrics"
+
+	// MetricsUpdateFreq is the command line flag to define how frequently tunnel metrics are updated
+	MetricsUpdateFreq = "metrics-update-freq"
+)

cmd/cloudflared/main.go

@@ -12,6 +12,7 @@ import (
 
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/access"
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/cliutil"
+	cfdflags "github.com/cloudflare/cloudflared/cmd/cloudflared/flags"
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/proxydns"
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/tail"
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/tunnel"
@@ -105,7 +106,7 @@ func commands(version func(c *cli.Context)) []*cli.Command {
 					Usage: "specify if you wish to update to the latest beta version",
 				},
 				&cli.BoolFlag{
-					Name:   "force",
+					Name:   cfdflags.Force,
 					Usage:  "specify if you wish to force an upgrade to the latest version regardless of the current version",
 					Hidden: true,
 				},

cmd/cloudflared/tail/cmd.go

@@ -18,8 +18,8 @@ import (
 	"nhooyr.io/websocket"
 
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/cliutil"
+	cfdflags "github.com/cloudflare/cloudflared/cmd/cloudflared/flags"
 	"github.com/cloudflare/cloudflared/credentials"
-	"github.com/cloudflare/cloudflared/logger"
 	"github.com/cloudflare/cloudflared/management"
 )
 
@@ -119,13 +119,13 @@ func buildTailCommand(subcommands []*cli.Command) *cli.Command {
 				Value:  "",
 			},
 			&cli.StringFlag{
-				Name:    logger.LogLevelFlag,
+				Name:    cfdflags.LogLevel,
 				Value:   "info",
 				Usage:   "Application logging level {debug, info, warn, error, fatal}",
 				EnvVars: []string{"TUNNEL_LOGLEVEL"},
 			},
 			&cli.StringFlag{
-				Name:    credentials.OriginCertFlag,
+				Name:    cfdflags.OriginCert,
 				Usage:   "Path to the certificate generated for your origin when you run cloudflared login.",
 				EnvVars: []string{"TUNNEL_ORIGIN_CERT"},
 				Value:   credentials.FindDefaultOriginCertPath(),
@@ -169,7 +169,7 @@ func handleValidationError(resp *http.Response, log *zerolog.Logger) {
 // logger will be created to emit only against the os.Stderr as to not obstruct with normal output from
 // management requests
 func createLogger(c *cli.Context) *zerolog.Logger {
-	level, levelErr := zerolog.ParseLevel(c.String(logger.LogLevelFlag))
+	level, levelErr := zerolog.ParseLevel(c.String(cfdflags.LogLevel))
 	if levelErr != nil {
 		level = zerolog.InfoLevel
 	}
@@ -183,9 +183,10 @@ func createLogger(c *cli.Context) *zerolog.Logger {
 // parseFilters will attempt to parse provided filters to send to with the EventStartStreaming
 func parseFilters(c *cli.Context) (*management.StreamingFilters, error) {
 	var level *management.LogLevel
-	var events []management.LogEventType
 	var sample float64
 
+	events := make([]management.LogEventType, 0)
+
 	argLevel := c.String("level")
 	argEvents := c.StringSlice("event")
 	argSample := c.Float64("sample")
@@ -225,7 +226,7 @@ func parseFilters(c *cli.Context) (*management.StreamingFilters, error) {
 
 // getManagementToken will make a call to the Cloudflare API to acquire a management token for the requested tunnel.
 func getManagementToken(c *cli.Context, log *zerolog.Logger) (string, error) {
-	userCreds, err := credentials.Read(c.String(credentials.OriginCertFlag), log)
+	userCreds, err := credentials.Read(c.String(cfdflags.OriginCert), log)
 	if err != nil {
 		return "", err
 	}
@@ -331,6 +332,7 @@ func Run(c *cli.Context) error {
 		header["cf-trace-id"] = []string{trace}
 	}
 	ctx := c.Context
+	// nolint: bodyclose
 	conn, resp, err := websocket.Dial(ctx, u.String(), &websocket.DialOptions{
 		HTTPHeader: header,
 	})