feat(agent): add -token-file flag to consul agent command

agent/config/builder.go

@@ -886,17 +886,17 @@ func (b *builder) build() (rt RuntimeConfig, err error) {
 		},
 
 		ACLEnableKeyListPolicy:    boolVal(c.ACL.EnableKeyListPolicy),
-		ACLInitialManagementToken: stringVal(c.ACL.Tokens.InitialManagement),
+		ACLInitialManagementToken: b.stringValOrFile(c.ACL.Tokens.InitialManagement, c.ACL.Tokens.InitialManagementFile, "acl.tokens.initial_management"),
 
 		ACLTokenReplication: boolVal(c.ACL.TokenReplication),
 
 		ACLTokens: token.Config{
 			DataDir:                        dataDir,
 			EnablePersistence:              boolValWithDefault(c.ACL.EnableTokenPersistence, false),
-			ACLDefaultToken:                stringVal(c.ACL.Tokens.Default),
-			ACLAgentToken:                  stringVal(c.ACL.Tokens.Agent),
-			ACLAgentRecoveryToken:          stringVal(c.ACL.Tokens.AgentRecovery),
-			ACLReplicationToken:            stringVal(c.ACL.Tokens.Replication),
+			ACLDefaultToken:                b.stringValOrFile(c.ACL.Tokens.Default, c.ACL.Tokens.DefaultFile, "acl.tokens.default"),
+			ACLAgentToken:                  b.stringValOrFile(c.ACL.Tokens.Agent, c.ACL.Tokens.AgentFile, "acl.tokens.agent"),
+			ACLAgentRecoveryToken:          b.stringValOrFile(c.ACL.Tokens.AgentRecovery, c.ACL.Tokens.AgentRecoveryFile, "acl.tokens.agent_recovery"),
+			ACLReplicationToken:            b.stringValOrFile(c.ACL.Tokens.Replication, c.ACL.Tokens.ReplicationFile, "acl.tokens.replication"),
 			ACLConfigFileRegistrationToken: stringVal(c.ACL.Tokens.ConfigFileRegistration),
 			ACLDNSToken:                    stringVal(c.ACL.Tokens.DNS),
 		},
@@ -1625,6 +1625,28 @@ func (b *builder) warn(msg string, args ...interface{}) {
 	b.Warnings = append(b.Warnings, fmt.Sprintf(msg, args...))
 }
 
+// stringValOrFile returns the token from the given value. If tokenFile is provided,
+// it reads the token from the file (trimming whitespace). If both token and tokenFile
+// are provided, tokenFile takes precedence (with a warning).
+func (b *builder) stringValOrFile(token *string, tokenFile *string, name string) string {
+	tokenVal := stringVal(token)
+	tokenFileVal := stringVal(tokenFile)
+
+	if tokenFileVal != "" {
+		if tokenVal != "" {
+			b.warn("%s is set and %s_file is also set. %s_file will be used.", name, name, name)
+		}
+		data, err := os.ReadFile(tokenFileVal)
+		if err != nil {
+			b.err = multierror.Append(b.err, fmt.Errorf("%s_file: %w", name, err))
+			return ""
+		}
+		return strings.TrimSpace(string(data))
+	}
+
+	return tokenVal
+}
+
 func (b *builder) checkVal(v *CheckDefinition) *structs.CheckDefinition {
 	if v == nil {
 		return nil

agent/config/config.go

@@ -793,10 +793,15 @@ type ACL struct {
 
 type Tokens struct {
 	InitialManagement      *string `mapstructure:"initial_management"`
+	InitialManagementFile  *string `mapstructure:"initial_management_file"`
 	Replication            *string `mapstructure:"replication"`
+	ReplicationFile        *string `mapstructure:"replication_file"`
 	AgentRecovery          *string `mapstructure:"agent_recovery"`
+	AgentRecoveryFile      *string `mapstructure:"agent_recovery_file"`
 	Default                *string `mapstructure:"default"`
+	DefaultFile            *string `mapstructure:"default_file"`
 	Agent                  *string `mapstructure:"agent"`
+	AgentFile              *string `mapstructure:"agent_file"`
 	ConfigFileRegistration *string `mapstructure:"config_file_service_registration"`
 	DNS                    *string `mapstructure:"dns"`
 

agent/config/flags.go

@@ -96,6 +96,7 @@ func AddFlags(fs *flag.FlagSet, f *LoadOpts) {
 	add(&f.FlagValues.Ports.SerfWAN, "serf-wan-port", "Sets the Serf WAN port to listen on.")
 	add(&f.FlagValues.ServerMode, "server", "Switches agent to server mode.")
 	add(&f.FlagValues.EnableSyslog, "syslog", "Enables logging to syslog.")
+	add(&f.FlagValues.ACL.Tokens.DefaultFile, "token-file", "Path to a file containing the ACL token to use as the default token. This can also be specified via the CONSUL_HTTP_TOKEN_FILE environment variable.")
 	add(&f.FlagValues.UIConfig.Enabled, "ui", "Enables the built-in static web UI server.")
 	add(&f.FlagValues.UIConfig.ContentPath, "ui-content-path", "Sets the external UI path to a string. Defaults to: /ui/ ")
 	add(&f.FlagValues.UIConfig.Dir, "ui-dir", "Path to directory containing the web UI resources.")

agent/config/runtime_test.go

@@ -905,6 +905,79 @@ func TestLoad_IntegrationWithFlags(t *testing.T) {
 			rt.DataDir = dataDir
 		},
 	})
+	run(t, testCase{
+		desc: "-token-file",
+		args: []string{
+			`-token-file=` + filepath.Join(dataDir, "token-file"),
+			`-data-dir=` + dataDir,
+		},
+		setup: func() {
+			writeFile(filepath.Join(dataDir, "token-file"), []byte("my-test-token\n"))
+		},
+		expected: func(rt *RuntimeConfig) {
+			rt.ACLTokens.ACLDefaultToken = "my-test-token"
+			rt.DataDir = dataDir
+		},
+	})
+	run(t, testCase{
+		desc: "acl.tokens.default_file in config",
+		args: []string{
+			`-data-dir=` + dataDir,
+		},
+		setup: func() {
+			writeFile(filepath.Join(dataDir, "token-file"), []byte("  token-from-file  \n"))
+		},
+		hcl: []string{`
+			acl {
+				tokens {
+					default_file = "` + filepath.Join(dataDir, "token-file") + `"
+				}
+			}
+		`},
+		json: []string{`{
+			"acl": {
+				"tokens": {
+					"default_file": "` + filepath.Join(dataDir, "token-file") + `"
+				}
+			}
+		}`},
+		expected: func(rt *RuntimeConfig) {
+			rt.ACLTokens.ACLDefaultToken = "token-from-file"
+			rt.DataDir = dataDir
+		},
+	})
+	run(t, testCase{
+		desc: "acl.tokens.default and default_file both set",
+		args: []string{
+			`-data-dir=` + dataDir,
+		},
+		setup: func() {
+			writeFile(filepath.Join(dataDir, "token-file"), []byte("token-from-file"))
+		},
+		hcl: []string{`
+			acl {
+				tokens {
+					default = "inline-token"
+					default_file = "` + filepath.Join(dataDir, "token-file") + `"
+				}
+			}
+		`},
+		json: []string{`{
+			"acl": {
+				"tokens": {
+					"default": "inline-token",
+					"default_file": "` + filepath.Join(dataDir, "token-file") + `"
+				}
+			}
+		}`},
+		expectedWarnings: []string{
+			"acl.tokens.default is set and acl.tokens.default_file is also set. acl.tokens.default_file will be used.",
+		},
+		expected: func(rt *RuntimeConfig) {
+			rt.ACLTokens.ACLDefaultToken = "token-from-file"
+			rt.DataDir = dataDir
+		},
+	})
 	run(t, testCase{
 		desc: "-ui",
 		args: []string{